Entomology & Nematology

Course Manual

ICAR-JRF (PGS) in Agriculture

Entomology & Nematology

 SS Yadav

 KS Bangarwa

 Surender S Dhankhar

 RK Pannu

Students’ Councelling & Placement Cell Directorate of Students’ Welfare In Collaboration with

College of Agriculture CCS Haryana Agricultural University, Hisar http://hau.ernet.in/

November, 2014

ICAR-JRF (PGS) in Agriculture Entomology & Nematology

Editors Dr SS Yadav Asistant Professor Department of Entomology

Dr KS Bangarwa Professor & Head Department of Forestry

Dr Surender S Dhankhar Assoc Director (C&P) Directorate of Students Welfare

Dr RK Pannu Dean College of Agriculture

Students’ Counseling and Placement Directorate of Students’ Welfare CCS Haryana Agricultural University, Hisar-125004 2014

CONTENTS CHAPTER #

TITLE OF THE CHAPTER (S)

AUTHOR (S)

PAGE #

KK MRIG

1-13

SS YADAV AND GS YADAV YOGESH KUMAR

14-21

3.

CLASSIFICATION OF ANIMAL KINGDOM UP TO CLASS, DISTINGUISHING CHARACTERS UP TO ORDERS AND FAMILIES (IMPORTANT ONLY) IN CLASS INSECT GENERAL ORGANIZATION OF AN INSECT BODY (EXTERNAL MORPHOLOGY) PHYSIOLOGICAL SYSTEMS IN INSECTS

4.

METAMORPHOSIS AND MOULTING IN INSECTS

29-32

5.

BASIC PRINCIPLES OF INSECT PEST MANAGEMENTCULTURAL, BIOLOGICAL & INSECTICIDAL QUARANTINE AND REGULATORY ASPECTS FOR INSECT PEST MANAGEMENT (CIB AND ANTI-LOCUST ORGANIZATION) CLASSIFICATION OF INSECTICIDES AND NOVEL INSECTICIDE GROUPS INSECTICIDE RESISTANCE IN INSECTS AND ITS MANAGEMENT ROLE OF BIOAGENTS IN IPM OF CROP PESTS

GS YADAV AND SS YADAV DEEPIKA KALKAL HARISH KUMAR

46-53

SS YADAV AND SHIVA KUMAR K RK SAINI

54-69

PALA RAM

79-85

INSECTS AS VECTORS OF PLANT DISEASES AND THEIR MANAGEMENT INSECT - PLANT RELATIONSHIP

GS YADAV

86-89

SP SINGH

90-96

USEFUL AND BENEFECIAL INSECTS LIKE HONEYBEES, LAC INSECT AND SILK WORMS MAJOR INSECT-PESTS OF SUGARCANE, COTTON, MAIZE AND THEIR MANAGEMENT MAJOR INSECT PESTS OF CEREALS AND MILLETS AND THEIR MANAGEMENT MAJOR INSECT PESTS OF PULSES AND THEIR MANAGEMENT MAJOR INSECT PESTS OF OILSEEDS AND THEIR MANAGEMENT MAJOR INSECT- PEST OF FORAGES AND THEIR MANAGEMENT LATEST TRENDS IN PEST MANAGEMENT IN VEGETABLE CROP

SK SHARMA

97-111

SUNITA YADAV

112-122

VK KALRA

123-133

ROSHAN LAL

134-144

SP SINGH

145-150

SP SINGH

151-156

SS SHARMA

157-162

1.

2.

6.

7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18.

22-28

33-45

70-78

19. 20. 21. 22. 23. 24.

RECENT APPROACHES FOR STORE GRAINS PEST MANAGEMENT MAJOR INSECT PESTS OF FRUIT CROPS AND THEIR MANAGEMENT MAJOR INSECT PESTS OF PLANTATION CROPS AND THEIR MANAGEMENT MAJOR NON INSECT-PESTS OF AGRICULTURAL CROPS (RODENTS, BIRDS ETC.) INSECT PESTS OF HOUSEHOLD, MEDICAL AND VETERINARY IMPORTANCE AND THEIR CONTROL OCCURRENCE, BIOSYNTHESIS AND BIOACTIVITY OF INSECT PROTECTIVE TRANSGENIC SIGNALING OF INSECT INDUCIBLE COMPOUNDS IN HOST PLANTS

SS SHARMA

163-168

HD KAUSHIK

169-188

HD KAUSHIK

189-198

SUNITA YADAV

199-210

KK MRIG

211-217

KK DAHIYA

218-222 225 25

NEMATOLOGY 25.

NEMATODE PEST MANAGEMENT PRACTICES

RS KANWAR

223-232 227-235

26.

ENTOMOPATHOGENIC NEMATODES

KUMKUM WALIA

233-240 236-243

Course Manual on ICAR-JRF (PGS) in Agriculture – Entomology and Nematology Eds SS Yadav, KS Bangarwa, Surender S Dhankhar and RK Pannu CCS HAU, Hisar 2014, pp 1-13

CLASSIFICATION OF ANIMAL KINGDOM UP TO CLASS, DISTINGUISHING CHARACTERS UP TO ORDERS AND FAMILIES (IMPORTANT ONLY) IN CLASS INSECT KK Mrig Department of Entomology CCS HAU, Hisar 1. Old Classification of Insects Classification of animals may be defined as ―the orderly arrangement of individuals into groups, groups into systems, in which the data about the kinds determine their position in the system and thereafter are reflected in that position‖. Efforts are being made from time to time to classify the animals in an attempt to express as correctly as possible their exact relationships with each other. Where two animals differ from each other in definite but relatively small structural characters, they are said to be distinct species. Biologically ―species are groups of actually interbreeding natural populations which are reproductively isolated from such other groups‖. Species are grouped into a genus which is formed of a group of animals having similar characters. Different genera are classified into a higher group called family. An order is composed of different families with a similarity of major features. Later the morphological characters of insects were mainly studied in attempting their classification. Present day classification of insects is based on their metamorphosis and their fundamental plan of structure. The presence or absence of wings is regarded as an important character in insect classification. Primitive insects were wingless and from these wingless parents the present winged insects are evolved. The idea of insect classification into orders was suggested by Linnaeus (1735-1768). He divided the group Insecta into seven orders. Since Linnaeus, many modifications in insect classification were suggested by different workers. Thus the seven original orders of Linnaeus were increased by later workers to 27 and then subsequently to 29. Later entomologists adopted the family as the unit of classification. As per old classification, the class insecta includes 29 orders and is divided into two main sub classes Apterygota or wingless insects and Pterygota or winged insects. The subclass Apterygota includes very few insects like silverfish, springtails, diplurans, proturans and all are ametabolous. The Apterygotes were grouped under four orders. The subclass Pterygota include a vast majority of common insects like moths, butterflies, beetles, grasshoppers, bees, flies, bugs etc. Insects like lice, bird lice and fleas are included under Pterygota because it is believed that the wingless condition. Of these insects is an acquired one due to their parasitic life. The subclass Pterygota is further divided into Exopterygota and Endopterygota. Exopterygota are hemimetabolous including 16 orders, whereas Endopterygota are holometabolous and grouped under 9 orders. The detailed classification is given below: 2. New Classification of Insects Insects range from minute to large (0.2 mm—30 cm) and their mouth parts are exposed (ectognathous).The thorax is distinct in flighted adult stages, associated with development of wings and the required musculature. Thoracic legs have more than five segments. The abdomen is primitively II- segmented. The tracheal system is well developed with spiracles present on 1

both the thorax and abdomen. Larval / nymphal development is epimorphic. The class Insecta now includes 30 insect orders and these 30 orders have been traditionally divided into 2 groups. I) Monocondylia (represented by one small order Archaeognatha in which each mandible has a single posterior articulation with the head). ii) Dicondylia (contains all other 29 orders including Zygentoma and Pterygota. The mandibles are characterized by a secondary anterior articulation in addition to the primary posterior one). Pterygota are the winged or secondarily wingless insects. The thoracic segments of adults are usually large. The meso and metathorax are variably united to form a pterothorax. Abdominal segments are II or less and lack styles and vesicular appendages like those of Apterygotes.‘The Pterygotes are divided into three divisions; i) Division Ephemeroptera, ii) Division Odonata, iii) Division Neoptera. Divisions Ephemeroptera and Odonata together form informal group Palaeoptera. Palaeoptera: In Palaeoptera, insect wings cannot be folded against the body at rest, because the articulation is via axillary plates that are fused with veins, It includes order Ephemeroptera and Odonata. Neoptera: Neopterans (new wings) have wings capable of being folded back against their abdomen when at rest. The wing articulation is derived from separate movable scierites in the wing base. Three further subdivisions are suggested as Polyneoptera, Paraneoptera and Endopterygota. i) Subdivision: Polyneoptera (Orthopteroid-Plecopteroid Assemblage) A group of II orders is termed as Polyneoptera. This grouping comprises the orders Plecoptera, Mantodea, Blattodea, Isoptera, Grylloblattodea, Mantophasmatodea, Orthoptera, Phasmatodea, Embiidina (Embioptera), Dermaptera and Zoraptera ii) Subdivision: Paraneoptera (Hemipteroid Assemblage) This division comprises the orders Psocoptera, Phthiraptera, Thysanoptera and Hemiptera. This group is defined by derived features of the mouthparts, including the slender, elongate maxillary lacinia separated from the stipes and a swollen postclypeus containing an enlarged cibarium (sucking pump) and the reduction in the tarsomere number to three or less. iii) Subdivision: Endopterygota (= Holometabola) Endopterygota comprises insects with holometabolous development in which immature iristars are very different from their adults. The resting stage or pupa is non-feeding and precedes an often active pharate adult. This subdivision includes 11 orders; Coleoptera, Neuroptera, Megaloptera, Raphidioptera, Strepsiptera, Mecoptera, Siphonaptera, Diptera, Hymenoptera, Trichoptera and Lepidoptera. The detailed summary of new classification is as follows. DIAGNOSTIC FEATURES OF THE THREE NON-INSECT HEXAPOD ORDERS 1. Class and Order: Protura (Proturans) -

Proturans are small to very small in size (0.5 to 2.5 mm long). They are wingless, eyeless and without antenna. The mouthparts are entognathous within the folds of head. 2

-

Legs five-segmented. Adult abdomen 12-segmented without eerci. Immature stages are like small adults but with fewer abdominal segments. Families: Eosentomidae, Sinentomidae, Protentomidae, Acerentomidae

2. Class and Order: Diplura (Diplurans) Diplurans are small to medium in size (2-5 mm, exceptionally upto 50 mm). They are wingless and eyeless. The mouthparts are entognathous. Antennae are long like string of beads. Abdomen is 10-segmented, with some segment having small styles Terminal cerci are filiforrn to forceps-like. Immature stages are hke small adults 3. Class and Order: Collembola (Springtails) Minute to small (usually 2-3 mm, but upto 12 mm), soft bodied and wingless The mouthparts are entognathous. Antennae are present (4-6 segmented). Compund eyes absent. Legs are four-segmented. Abdomen six-segmented with sucker-like ventral tube and forked jumping organ. Cerci absent DIAGNOSTIC FEATURES OF THE APTERYGOTE INSECT ORDERS 1. Order: Archaeognatha (Bristletails) -

Archeognathans are moderate sized insects (6-25 mm). The body is elongate-cylindrical. They are wingless, with humped thorax. Mouthparts are hypognathous (directed downward). Families: Machilidae, Meinertellidae.

2. Order: Zygentoma or Thysanura (Silveifish) -

Zygentomans are moderate sized (5-30 mm), dorso-ventrally flattened with silvery scales They are wingless. The head is hypognathous to slightly prognathous.

DIAGNOSTIC FEATURES OF THE PTERYGOTE INSECT ORDERS (DIVISIONS: EPHEMEROPTERA AND ODONATA) 3. Division and Order: Ephemeroptera (Mayflies) -

The insects are small to large in size. Adults have non-functional strongly reduced mouthparts and large compound eyes.

4. Division and Order: Odonata (Dragonfliesand Damselflies) -

The adults are medium to large in size. They are expert aerial fliers; with two pairs of similar net-veined wings. Head mobile, with large compound eyes separated or nearly in contact. Mouthparts are mandibulate (biting type), antennae short bristle-like. These are winged; with fore and hind wings equal or hind wings wider than forewings Abdomen long, slender terminating in clasping organs. 3

Immature stages (nymphs) are aquatic, stout or narrow, with extensible terminal or rectal gills.

labial ―mask‖,

4.1 Suborders of Odonata: There are three suborders, i) Anisoptera (Dragonflies), ii) Zygoptera (Damseiflies) and iii) Anisozygoptera (Dragonflies). Important suborders are characterized as under: Anisoptera - Hind wings are wider than fore wings. - Compound eyes are separated (Fig.6.6 B) - Eggs laid on the water or on aquatic plants or rarely in their stems. - Nymphs respire through tracheal gills inside of the rectum, and the forcible ejection of water from the anus propels the nymphs forward.

Zygoptera - The fore wings and hind wings are equal. - Compound eyes are nearly in contact (Fig.6.6 A). -Eggs thrust into the stems of aquatic plants, often beneath water. - Nymphs respire by three leaf-like tracheal gills, projecting from the end of the abdomen.

DIAGNOSTIC FEATURES OF THE PTERYGOTE INSECT ORDERS (DIVISION NEOPTERA; SUB DIVISION POLYNEOPTERA) 5. Order: Plecoptera (Stoneflies) They are medium in size. Mouthparts are weak mandibulate. Antennae fihiform and compound eyes are bulging. Fore and hind wings are nearly equal (subequal) in size. At rest, wings partly wrap abdomen and extend beyond abdominal apex, wing reduction is frequent. Adult stoneflies are weak fliers and seldom found away from banks of streams or lakes. Abdomen is soft with filamentous cerci. Immatures (nymphs) are aquatic resembling wingless adults, often with gills on abdomen. 6. Order: Isoptera (Termites or ―White ants) They are social insects with polymorphic caste system of reproductives workers and soldiers The insects are small to moderately sized (500 13. To avoid cross-resistance, the crop may be sprayed with a) Insecticides having stomach and contact action b) Insecticides with different formulations c) Insecticides with distinctly different mode of action

77

d) Insecticides having systemic action 14. In d i scr i mi na ti n g d o s e tec h n iq ue, th e i n s ect s ar e e xp o s ed t o a) No r ma l d o s e o f a n in s ect ic id e gi v i n g co mp le te k il l b) Do ub le t h e d o se o f a n i n sec ti cid e gi v i n g co mp le te k il l c) T rip le t he d o se o f a n in se ct ic id e gi v i n g co mp le te k il l d) Do s e o f a n i ns ec tic id e gi v i n g 5 0 % ki ll 15. Decr ea sed s lo p e o f t h e r e gr e s sio n li ne i n b io a ss a y st ud ie s me a n s

a) T he p o p ul at io n i s r es i st an t b) T he p o p ul at io n i s s u sce p tib l e c) T he p o p ul at io n i s he tero ge no u s d) No s i g ni fic a nce o f slo p e va l ue 16. In a h i g hl y r es i st a nt a nd ho mo ge n o us p o p u lat io n, t h e re gre s sio n li ne wi ll b e a) T o ward s Y -a x is wi t h h i g h slo p e b) T o ward s Y -a x is wi t h lo w s lo p e c) A wa y fro m Y -a xi s wi t h hi g h s lo p e d) A wa y fro m Y -a xi s wi t h lo w slo p e

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ROLE OF BIOAGENTS IN IPM OF CROP PESTS Pala Ram Department of Entomology CCS HAU, Hisar Arthropods constitute about 75 per cent of all animal species. Many arthropod species are potentially dangerous that cause direct injury and transmit diseases to human beings and domestic animals, damage crops, infest stored products and destroy wooden structures. Synthetic chemical insecticides have played important role in the control of arthropod pests of crops, human beings, livestock and poultry and in the reduction of insect-borne diseases for nearly 70 years. Indiscriminate use of insecticides has brought about several problems like pollution of our environment, killing of wildlife, toxic residues in food, feed and fodder, development of pest resistance and resurgence, serious health hazards to man and animals, and elimination of the farmer friendly insects from the crop ecosystems. It is estimated that less than one per cent of pesticide applied reaches the target pest while 99 per cent reaches non-target sectors. Low doses of many insecticides are toxic to humans and other animals and some insecticides are suspected to be carcinogens. As a result many researchers, farmers and home owners are seeking less hazardous alternatives to the conventional synthetic insecticides. Biological control of arthropod pests by using their natural enemies is one such approach. Insect-pest management (IPM) in crops begins by taking right decisions at right time, such as growing crops that are naturally resistant to insect-pests, choosing sowing times that prevent pest outbreaks. Careful management in both time and space of planting not only prevents insect-pests but also increases population of their natural enemies that have natural capability to control them. Other methods generally employed for the management of insect-pests are: clean cultivation, rotating crops, encouraging natural biological agents for control of insect-pests, using physical barriers for protection from insect-pests, modifying habitat to encourage pollinators and natural enemies of insect-pests and using semiochemicals such as pheromone attractants that trap pests. Biological control is an important component of IPM. It involves the use of natural enemies of insect-pests which can be divided into three main groups like predators, parasitoids and pathogens. Principles of biological control Biological control has been defined as the ―actions of parasites, predators, and pathogens in maintaining another organism‘s density at a lower average than would occur in their absence‖ Biological control is an important component of integrated pest management. About 95 per cent of the potential arthropod pests are kept below damaging level by various biotic and abiotic factors and all the control methods used today are targeted at the remaining five per cent arthropod pest species. Biological control is not a new concept. As early as in 5000 B.C., the Chinese were placing bamboo poles between the ant nests and fruit trees to make it easier for the ants to prey on citrus scales. In the 1750s, the British and the French transported mynah birds 79

from India to Mauritius to control locusts. More than 5,000 introductions of about 2,000 species of exotic arthropod natural enemies, for the control of arthropod pests in 196 countries or islands have been made during the past 120 years and more than 150 species of natural enemies are currently commercially available. In India, 161 exotic biological control agents have been studied against crop pests and weeds. Of these, four species provided partial control, four substantial and six recurring economic benefits worth millions of rupees in addition to environment protection. More than 26 biological control agents from India have been successfully established in other countries and are providing substantial economic benefits. International Organization for Biological Control (IOBC) of noxious animals and plants coordinates biological control activities worldwide and it has six regional sections each in Africa, Asia, East Europe, North America, South America and West Europe and many working groups in different areas of research. In India, National Bureau of Agriculturally Important Insects (NBAII) (formerly Project Directorate of Biological Control) in Bangalore is the nodal institute at national level for research and development on all aspects of work on harnessing resources of insects including biological control of crop pests and weeds. Biological control is expected to make up 35 to 40 per cent of all crop protection methods by the year 2050. Types of biological control agents Three types of organisms, namely, predators, parasitoids and pathogens are used as the agents in various biological control programmes. Predators A predator is generally defined as an organism which kills and consumes several individuals or preys during its life cycle. Generally, predators are larger than their prey and are mobile. They are usually not very host specific and kill the host immediately. Usually adults and immatures both are predatory and tend to be active day and night. Ladybird beetles, green lacewings, spiders, frogs, birds are examples of predators. Parasitoids A parasitoid (occasionally referred to as parasite by some authors) is generally defined as an organism that lives, feeds, completes its life cycle on a single host and kills it. Parasitoids are generally smaller than their host. They are usually very host-specific. A parasitoid is usually parasitic in immature stage while an adult is free living and feeds on the nectar and host fluids etc. Unlike the predators, parasitoids kill their host slowly. Parasitoid adults are active only during the day. Wasps and flies are examples of parasitoids. Pathogens Pathogens are those organisms which cause diseases in other organisms. They are sometimes referred to as microbial pesticides. They include viruses, bacteria, fungi, protozoa and nematodes. A wide range of pest species such as weed plants, fungi, nematodes, bacteria, protozoa and arthropods are afflicted by disease causing agents which prevent them from reaching damaging level or greatly reduce their potential to cause damage. Pathogens mostly require a very specific environment that is difficult to create in the target area. Examples of pathogens include Bacillus popilliae Dutky, which causes milky disease in Japanese beetle, Bacillus thuringiensis Berliner, which causes disease in many lepidopterous caterpillars and many fungal and viral pathogens which cause diseases in insects. Characteristics of potential natural enemies of pests A natural enemy, to be successful in a biological control programme, must have a number of features. An arthropod natural enemy must have a high searching capacity. This characteristic is very critical when the host is scarce. A successful natural enemy must keep the host at low 80

population levels. The natural enemies must be able to occupy the same areas as occupied by the host. A natural enemy should be fairly host specific especially in the case of parasites and pathogens. The life cycle of the natural enemy must synchronize with that of the host. Effective natural enemies usually have a very high reproductive rate and a short developmental period. Finally, a very important characteristic of biological control agents is that they must be easy to mass rear under laboratory conditions. Approaches in biological control of pests Several steps in a sequence are followed in any biological control programme. These sequences ensure that the beneficial organisms do not turn out to be a pest itself. Exploration The first step is to search the literature in order to find out the areas where the pest, against which biological control programme is to be initiated, is not a pest. These areas are usually the native habitat of the host plant and the pest where these live in harmony and a natural balance is maintained. When such an area is found, a team of scientists is sent to study the reason why the pest is not serious in its native habitat. Such studies always lead to the exploration of effective natural enemies of the pest in the native habitat. Importation The next step in the biological control process involves importation of the natural enemy. It involves a quarantine period for all imported organisms. During this period, extensive bioecological and host preference studies are conducted to answer the questions like where and how the natural enemy lives and reproduces and the spectrum of its potential hosts etc. This step is necessary so that we do not introduce an organism that may create problems rather than solving them. Augmentation Augmentation is the third step which involves mass rearing and release of natural enemies of both native and exotic pests. Natural enemies are generally reared in large numbers in laboratories and released in the target areas. The release of natural enemies may involve inundation or inoculation. In inundation, the target area is flooded with large number of natural enemies. Normally such a release will bring the pest under control quickly as in the case of insecticides and it is hoped that the natural enemies will become permanently established in the area. Egg parasitoid, Trichogramma species which parasitises the eggs of several lepidopterous pests is mass released in crops like cotton, rice, sugarcane, maize, sorghum, tomato etc. to control lepidopterous pests (Table 1). Inoculation of an area usually involves much lower number of natural enemies. It is designed to allow the establishment of a biological control agent in an area by improving the natural enemy-pest ratio. Conservation The last step in the biological control process is the conservation of released natural enemies. This step is very important because if we do not conserve released natural enemies we will have to continuously introduce them in the target area, which will be uneconomical. Through conservation practices we create conditions that enable the control agent to stay and live in the target area. Knowledge of the biology and ecology of the natural enemies is important as it will enable us to provide suitable protective sites for survival especially during the off-season. Cultural practices and selective use of pesticides can help in conserving native and introduced biological control agents.

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Table 1. Schedule of Trichogramma releases against various lepidopterous pests Crop Insect pest Trichogramma Rate of Interva No. of Days spp. release l of releases after (,000/ha) release sowing/ (days) planting Sugarcane Shoot borer T. chilonis 50 10 4-6 45 Top borer T. japonicum 50 10 4-6 60 Stalk borer Internode borer T. chilonis 50 10 8-10 90 Gurdaspur borer Cotton American T. chilonis 150 7 6 45 bollworm or (Helicoverpa T. brasiliense spp.) or Pink bollworm T. achaeae Spotted bollworm Maize, Maize borer T. chilonis Sorghum 75 7 6 45 Tomato Tomato fruit T. brasiliense 50 7 6 45 borer or T. chilonis Paddy Stem borer T. japonicum 50 7 6 30 Leaffolder T. chilonis 50 7 6 30 Successful examples of biological control of crop pests The first well planned successful biological control attempt involved the control of cottony cushion scale, Icerya purchasi Maskell, a pest of citrus in USA during 1888. Vedalia beetle, Rodolia cardinalis Mulsant, an important natural enemy of the pest, was imported from Australia for field release. The complete control of the pest was achieved within 18 months. Following the success of this programme, the beetle has been imported to control this scale in over 50 other countries. In India, I. purchasi was probably introduced from Sri Lanka and it was first reported from Nilgiris (Tamil Nadu) in 1928 as a pest of cultivated wattle, Acacia decurrens Willd. and other Acacia spp. The beetle, R. cardinalis was introduced to India from USA and South Africa and was released in the Nilgiris in 1930. The beetle successfully controlled I. purchasi. Similarly, San Jose scale, Diaspidiotus perniciosus (Comstock), a pest of apple in northwestern India was successfully controlled by introducing an aphelinid parasitoid, Encarsia perniciosi (Tower) from California in 1958. Apple wooly aphid, Eriosoma lanigerm (Hausmaan), a pest of apple was also successfully controlled by importing and releasing an aphelinid parasitoid, Aphelinus mali (Haldeman) from UK to Kulu Valley (Himachal Pradesh) in 1963. Biological control of cassava mealybug, Phenacoccus manihoti Matile-Ferrero in Nigeria by importing and releasing an encyrtid parasitoid, Epidinocarsis lopezi (De Santis) from Paraguay in 1981, is one of the recent and outstanding examples. Presently, cassava mealybug has been virtually eliminated in 30 African countries and no longer poses a serious threat to most cassava growing regions. Similarly, the neotropical spider mite, Mononychellus tanajoa (Bondar), which was discovered attacking cassava in East Africa in the early 1970s, was successfully controlled by introducing natural enemies from northeast Brazil. Approximately 6.1 million phytoseiids of 82

the species Neoseiulus idaeus (Denmark and Muma), Typhlodromalus manihoti Moraes and Typhlodromalus aripo DeLeon were released at more than 400 sites in 20 countries between 1989 and 2000. Among these, T. aripo established and spread in sub-Saharan Africa covering more than 3.8 million square kilometres of the cassava belt in less than 10 years. The economic return for this predator has been estimated to be equivalent to hundreds of millions of dollars in food aid each growing season if yield losses had to be replaced. An excellent example of augmentative biological control is the inundative releases of egg parasitoids belonging to genus Trichogramma. Worldwide, over 32 million ha of agricultural crops and forests are treated annually with Trichogramma spp. in 19 countries, mostly in China and republics of the former Soviet Union. In Europe, augmentative releases of Trichogramma species against European corn borer, Ostrinia nubilalis (Hubner) were found as effective as insecticides. In 1993, about 67,000 acres of corn were treated with Trichogramma in France, Germany and Switzerland. In India, several trichogrammatids have been utilized as biological control agents against many insect pests of crops such as sugarcane, cotton, rice, pulses, castor, finger millet, sorghum, maize, fruits, vegetables and forests trees. Sugarcane leafhopper, Pyrilla purpusilla Walker is the most destructive pest of sugarcane in many parts of the Indian subcontinent. First outbreak of P. purpusilla occurred in 1930-31 and since then, it had been appearing in an epidemic form year after year. In Haryana, the pest has been successfully controlled by multiplying and augmenting three egg parasitoids, namely, Ooencyrtus papilionis Ashmead, Tetrastichus pyrillae Crawford, Cheiloneurus pyrillae Mani and one nymphal-adult parasitoid, Epiricania melanoleuca Fletcher. For the last 30 years, no insecticide application was made against this pest thus saving crores of rupees every year besides protecting the environment. Recently, the solenopsis mealybug, Phenacoccus solenopsis Tinsley invaded the Indian subcontinent and caused widespread and serious damage to cotton crop in 2007. Phenacoccus solenopsis was found to be heavily attacked by a nymphal endo-parasitoid, Aenasius bambawalei Hayat in 2008. During 2009, the activity of the parasitoid, A. bambawalei increased and the pest was successfully controlled by the parasitoid thus saving crores of hard earned money of the farmers. It was reported as a classic example of fortuitous biological control. Til hawk moth, Acherontia styx Westwood, a pest of sesame in Haryana, is being naturally controlled by natural enemies mainly (67.6%) by Trichogramma chilonis Ishii. Microbial pathogens, namely, bacteria, viruses, fungi, nematodes, protozoa etc. are also associated with different species of insects and many of which have been exploited for the control of crop pests. Bacillus thuringiensis Berliner (B.t.) has been most widely exploited as a microbial control agent. In India, B.t. based microbial pesticides are recommended and widely used against lepidopterous pests in crops like vegetables, fruits, maize, cotton, small grain cereals and forests etc. The first baculovirus developed for commercial use was Elcar (Sandoz Inc.), nuclear polyhedrosis virus of Helicoverpa zea (Boddie) (HzSNPV), primarily developed for use on cotton in USA in 1975. The control of velvetbean caterpillar, Anticarsia gemmatalis (Hubner) on soybean crop by AgNPV, proved very successful and ecological sustainable. The virus is presently used on 2.0 million ha of soybean in Brazil. It is estimated that cumulative use of AgNPV reached approximately 23,000,000 ha, which represents savings to farmers at about US$ 161 million. In India, biopesticedes based on HaNPV and Spodoptera litura NPV have been tested and used in different crops. The white muscardine fungus, Beauveria bassiana (Balasamo) Vuillemin has been detected from over 700 species of insects. It is effective against a number of important pests including the European corn borer, codling moth, Japanese beetle, Colorado 83

potato beetle, chinch bug, cabbage caterpillar, cotton whitefly and tarnished plant bug. The nematodes in the families Heterorhabditidae and Steinernematidae have been used in the biological control of insect pests because they have the ability to quickly kill the insects due to their mutualistic association with the bacteria in the genera Photorhabdus and Xenorhabdus (Enterobacteriaceae), respectively. India has a great potential to exploit these beneficial nematodes for the suppression of insect pests. Recent emphasis on mass production and formulation technologies of these nematodes stresses a need to implement safer and effective pest control methods. Suggested readings: Burges, H. D. and Hussey, N. W. 1971. Microbial Control of Insects and Mites. Academic Press. De Bach, P. 1964. Biological Control of Insect Pests and Weeds. Chapman & Hall. Dhaliwal, G. S. and Arora, R. 2001. Integrated Pest Management: Concepts and Approaches. Kalyani Publ. Gerson, H. and Smiley, R. L. 1990. Acarine Biocontrol Agents – An Illustrated Key and Manual. Chapman & Hall. Huffaker, C. B. and Messenger, P. S. 1976. Theory and Practices of Biological Control. Academic Press. Ignacimuthu, S. S. and Jayaraj, S. 2003. Biological Control of Insect Pests. Phoenix Publ. Saxena, A. B. 2003. Biological Control of Insect Pests. Anmol Publ. Van Driesche and Bellows, T. S. Jr. 1996. Biological Control. Chapman & Hall. Multiple choice questions 1. Of the total insect species, predators constitute about A. 10% B. 20% C. 30% D. 40% 2. Epiricania melanoleuca is a parasitoid of A. Cotton leafhopper B. Sugarcane leafhopper C. Rice planthoppers D. Non of the above 3. Stone flies belong to order A. Psocoptera B. Trichoptera C. Ephemeroptera D. Plecoptera 4. Tiger beetles belong to family A. Carabidae B. Cicindelidae C. Dytiscidae D. Meloidae 5. Which one is the correct scientific name A. Coccinella septempunctata B. Coccinella septumpunctata C. Coccinela septempunctata D. Cocinella septumpunctata 6. Which of the following is not a predator

A. B. C. D. 7. family A. B. C. D. 8. A. B. C. D. 9. A. B. C. D. 10. A. B. C. D.

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Yellow wasp Ichneumonid wasp Rove beetle Stethorus beetle Which of the following is not a parasitic Aphelinidae Cecidomyiidae Trichogrammatidae Encyrtidae Which predator is smallest in size Scymnus coccivora Stethorus species Cheilomenes sexmaculata Nephus regularis Aenasius bambawalei is a parasitoid of Papaya mealybug Solenopsis mealybug Cassava mealybug Pyrilla perpusilla Cheilomenes sexmaculata is a Predator Primary parasitoid Hyperparasitoid Pathogen

11. Polyhedron is present in A. Fungus B. Bacterium C. Virus D. None of the above 12. Ninety per cent of the known parasitoids belong to order A. Diptera B. Hymenoptera C. Lepidoptera D. Coleoptera 13. An ichneumonid and braconod parasitoid is differentiated on the basis of A. Marginal vein B. Costal vein C. Recurrent vein D. None of the above 14. Meconium is present in A. Fungi B. Predators C. Hymenopterous parasitoids D. Phytophagous insects 15. The parasitoid which destroys culture of rice moth in laboratory is A. Trichogramma chilonis B. Chelonus blackburni C. Telenomus remus

D. Bracon hebetor 16. Which predator is monophagous A. Brumoides suturalis B. Scymnus coccivora C. Cheilomenes sexmaculata D. Rodolia cardinalis 17. Which predator is bigger in size A. Scymnus coccivora B. Stethorus species C. Cheilomenes sexmaculata D. Nephus regularis 18. Which of the following is not a parasitoid A. Encarsia formosa B. Trichogramma chilonis C. Aenasius bambawalei D. Aphidoletes aphidimyza 19. Which of the family belong to order Hymenoptera A. Pentatomidae B. Sphecidae C. Asilidae D. Staphylinidae 20. Blister beetle is a A. Pest B. Predator C. Both pest and predator D. Sacrophagous

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Foundation Course Manual on ICAR-JRF (PGS) in Agriculture – Entomology and Nematology Eds SS Yadav, KS Bangarwa, Surender S Dhankhar and RK Pannu CCS HAU, Hisar 2014, pp 86-89

INSECTS AS VECTORS OF PLANT DISEASES AND THEIR MANAGEMENT GS Yadav Department of Entomology CCS HAU, Hisar Insects, besides directly damaging the crops, sometimes are responsible for the spread of viral, fungal, mycoplasmal and bacterial diseases in plants. Some common insect vectors & their classification: 1. Whitefly: Bemisia tabaci, family- Aleurodidae, order- Hemiptera 2. Aphid: Myzus persicae, Aphidae, Hemiptera 3. Mealybug: Drosicha mengiferae Coccidae, Hemiptera Distinct white covering over the body 4. Leaf hopper: Nephotettix virescens Cicadellidae, Hemiptera 5. Plant hopper: Sogatella furcifera (White backed planthopper), Delphacidae, Hemiptera 6. Thrips: Thrip tabaci Thripidae, Thysanoptera. Adults slender, yellowish brown males wingless, females have long narrow strap like wings. Insect vectors of plant viruses are known to occur in only six of the major orders of insect: OHemiptera-sub-order Homoptera (aphids, leafhoppers, whiteflies, mealybugs, scales); Thysanoptera (Thrips), Heteroptera (plant bugs), Coleoptera (beetles), Orthoptera (grasshoppers) and Dermaptera (earwings). In some cases, the insects make the wounds through which the fungi or bacteria penetrate the plant and also transport the micro-organisms from plant to plant. In some cases the insects may not be that important in transporting the spores of a fungus but may provide wounds through which windblown spores may enter. Among the fungus diseases transmitted by insects are the dutch elm disease and the blue strain of conifers which are transmitted almost entirely by bark beetle. Plant virus diseases, as a whole have become more prevalent and more destructive in recent years. This is because of a better recognition of virus diseases, exchange of plant materials from region to region facilitating spread of the virus to new areas. Plant pathogens are transmitted through contact, by contamination through ‗soil or other biological agencies, most important among them being insects, nematodes & mites. These biological agencies are called vectors. Most of these vectors belong to or-Hemiptera, particularly the aphids, leafhoppers, white flies, mealy bugs and thrips. Homopteran insects alone are known to transmit about 90% of the 300 known plant viruses. Among Homoptera, the aphids predominate and the ability of aphids to transmit a large no. of viruses is due to the fact that during their feeding there is no wholesale destruction of cells and viruses require living cells for their subsistence and multiplication. In case of sucking insects, the virus after acquisition from an infected plant source, passes from the vector body to healthy plant alongwith the saliva that is infected during feeding. Based on the route, and the type of transmission, the viruses are grouped into three principle types: i) In case of certain viruses, the insect has to feed on the source of virus for comparatively 86

long periods and the insects after such acquisition of virus becomes infective only after a certain period, ranging from several hours to 10-19 days which is called incubation period or latent period. The vector continues to be viruliferous for several days usually for rest of its life and it need not feed on virus source again and again to retain its infective capacity. Such viruses are called persistent viruses. Many of the leafhopper transmitted viruses are of this type. ii) Some viruses may multiply in the bodies of their respective vectors and are called propagative viruses. iii) In the third group of viruses, the vector is able to acquire the virus from a disease source and transmit it to a healthy plant by feeding for a few seconds or minutes. However, the infectivity of the vector is rapidly lost unless there is renewed access to a fresh source. Aphids are vectors in this category. Viruses exhibit selectivity as regards the vectors. There are viruses which are transmitted by a particular sp. of an insect and not by others, even though of the same genus. For instance, cabbage black ring spot is transmitted only by Myzus persicae but not by M. ornatus. A vector can also acquire and transmit more than one virus to the respective hosts. For instance the whitefly Bemisia tabaci transmits tomato leaf curl virus, papaya leaf curl, bhindi vein virus. Generally one type of virus disease is transmitted by one group of insects; the mosaics by aphids and leaf curl by whitefly. For transmission of viruses activity of the insect vectors is more important rather than their numbers. In case of aphids, it is the activity and no. of migrants insects that is important in the efficiency of virus transmission rather than the number of apterous individuals, which of course, are important in respect to their direct injury to the crop. Some of the insect vectors and the viruses transmitted by them are: Insect vector Virus Aphis gossypii Papaya mosaic, cucumber mosaic, chilli mosaic Myzus permiscae Cucumber mosaic A. craccivora Cowpea mosaic, papaya mosaic & cane mosaic B. tabaci Bhindi yellow vein mosaic, tobacco leaf curl, tomato leaf curl etc. Thrip tabaci Tomato spotted wilt

B.

Diseases caused by mycoplasma : Mycoplasma are organisms grouped between viruses & bacteria Mycoplasma transmitted by insects: Naphotethix virescens causing rice yellow dwarf Orosius albicinctus causing sesamum phyllody C. Fungal diseases In bajra, the ergot disease is mechanically carried by insects. D. Bacterial disease Bacterial wilt of corn caused by Xanthomonas stewartii is transmitted by flea beetle. Leaf curl disease of chillies: Vector is thrips (Scirtothrips dorsalis). Diseases in plant can be defined as the series of invisible and visible responses of plant cells and 87

tissues to a pathogenic organism or environmental factor that results in adverse changes in the form, function or integrity of the plant and may lead to partial impairment or death of plant cells or of the entire plant. Plant pathogens spread from the diseased individual to healthy individuals through various means like soil, water, air, insects, human beings etc. A vector is an organism capable of transmitting pathogens from one host to another. The insects, besides directly damaging the crops, sometimes become responsible for the spread of pathogen in plants. All those insects which acquire the disease causing organisms by feeding on the diseased plant are known as insect vector of the plant diseases. Insects having both piercing and sucking mouthparts and biting and chewing mouthparts are associated with disease transmission. Insects transmit the majority of described plant viruses. Insects and other vectors transmit 76 per cent out of the 697 virus species recognized by the International Committee on Taxonomy of viruses (ICTV). There, are currently four described mechanisms of insect transmission of plant viruses. They are (1) Non-persistent transrnission (2) semi-persistance transmission (3) persistent circulative and (4) persistent propagative transmission. Vector-virus transmission consists of several successive steps: acquisition of virions from an infected source, stable retention of acquired virions at specific sites through binding of virions to ligands, release of virions from the retention sites up to salivation or regurgitation and delivery of virions to a site of infection in a viable plant cell. Each step of this sequence is needed for transmission of these viruses to be successful. All plant viruses that are transmitted in a non-persistent manner are vectored by aphids. Studies have shown that the initial host-finding behaviour of aphid, which includes the sampling of sap taken from the host epidermis (probing), plays a major role in the acquisition and transmission of these viruses. Management of insect vectors: i) Grow virus resistant varieties. ii) Suitable cultural practices should be followed which include proper line to line and plant to plant spacing. iii) Mechanical removal of the initially infected viral plant twigs and digging them in soil. iv) Spray recommended insecticide i.e. malathion 50 EC 0.05% or dimethoate 30 EC 0.03% for the control of aphids, whitefly, mealybugs and leafhoppers etc. Insect vectors a.

…………… is numerically the most important sub-order containing plant virus vector.

b.

Thrips belongs to order…………

c.

YVMV is expanded as…………..

d.

Aphids transmit persistent/ non-persistent virus

e.

Most of the persistent propagative viruses are transmitter by…………

f.

Leaf curl of chillies is caused by…………….

g.

Longer feeding times gives higher transmission rates and……………. Persistence.

h.

………….are transmitted by Delphacid planthoppers.

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i.

Begomoviruses are transmitted exclusively by……………

j.

The nymphs of Bemisia tabaci are……………. Feeders.

k.

Whitefly belongs to family……………

l.

The foregut and hindgut are ectodermal origin whereas midgut is…………….

m.

Topsoviruses are normally transmitted by………….

n.

CLCV in cotton can be somewhat managed by controlling insect……….

o.

The full form of tops O virus is……………..

p.

Name a nematode which acts as vector.

q.

Name three families of or-coleoptera having vectors.

r.

Fungi that transmits virus………..

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INSECT - PLANT RELATIONSHIP SP Singh Department of Entomology CCS HAU Hisar About 10,000 years ago, man seems to have started to domesticate plants. The age of wild plants as a main source of human nutrition ended when man instead of collecting edible wild plants, started intentionally planting and maintaining those plants. The process of crop cultivation began with the gradual transformation of wild forms into cultivated plants (Panda and Khush, 1995). Plants are the most important source of food for humans, and as population increases plant products will continue to play an even increasing role in feeding people. Of the total food harvested, 98 per cent comes from the land and 2 per cent from the sea and inland waters. Of the world food harvest, plant products contribute about 80 per cent, and animal and marine products about 20 per cent. Historically, mankind has used only 5,000 plant species worldwide to meet food and other requirements (Paroda and Arora, 1991). This number is just a fraction of total world flora and has 'gradually decreased over centuries. Today, the world population is greatly dependent on 23 crop species - primarily the cereals like rice, wheat, maize and sorghum. Cereals occupy approximately 50 per cent of the cultivated land in the world and contribute half of the calories and total protein intake. Plants will continue to serve as the major source of food in the future (Heinrichs, 1988). The evolution of land plants seems to have been closely followed by the evolution of pests. The first land plants evolved in the Devonian, and the first undoubtedly phytophagous insects are known from the Carboniferous. The first record of winged insects almost coincided with the record of tall forest trees in the upper Carboniferous period. Thereafter, modern orders of phytophagous insects appeared steadily throughout the fossil record. The last to appear were the Lepidoptera, coincident with the rise of angiosperms in the Cretaceous. Several other important groups evolved after the appearance of the angiosperms and a number of primitive insects became extinct (Strong et al., 1984). The dominance of angiosperms, with their diversified plant surface characteristics, architecture and chemical factors, provided the three factors needed for insect proliferation, i.e. food, shelter and oviposition sites. These factors offered an ideal habitat for insects which consequently diversified themeselves in the ecosystem (Panda and Khush, 1995). Reciprocal adaptation and counter adaptation between plants and insect phytophages has been an important mechanism driving a steady increase in plant and insect diversity over a broad sweep of fossil record. Presently for every species of green plant, there is roughly a species of phytophagous insect (Table 1). Most insect orders are not phytophagous (20 of 29) but over half of insect species are phytophagous. This pattern implies major evolutionary barriers to eating plants. Once the barriers were breached, however, the great diversity and biomass of plants have been a spectacular resource. In natural ecosystems, phytophagous insects have coexisted in a complex relationship with plant communities. Different species of plant feeding insects had to search out their own host plants from the mixed wild 90

vegetation. For this purpose, the insects made use of various types of olfactory stimuli which work from long distances and taste stimuli which work in the vicinity of the host plant. In this search they had to face the dangers of annihilation by various abiotic and biotic factors. Therefore, the damage caused by insects was probably quite limited (Pradhan, 1983). Table 1. Abundance of species in the major taxa of animals and plants Sr.No. Major taxa % taxa No. of species 1. Green plants 22 308,000 2. Phytophagous insects 26 361,000 3. Saprophagous and predaceous 31 431,000 insects 4. Other vertebrates 15 213,000 5. Protozoa 2 30,000 6. Vertebrates 4 54,000 Pest problems originated with the origin of agriculture. As soon as the land was cleared of natural vegetation and replaced by a single species of food plant, humans came into conflict with phytophagous insects. These insects and other organisms feeding on the valuable crops which humans planted were called as pests. Broadly speaking, a pest means any organism which is in competition with humans for some resource. In agriculture, a phytophagous insect is labelled as a pest when its population is high enough to cause significant damage in yield or quality of any of the economic plants grown by man. Not only did the insect pests originate with agriculture, but the intensity of pests continued to increase with the intensification of agriculture. According to various estimates, the insects came into existence 350-500 million years ago. The earliest known fossil insect is Rhyniella praecursor, a Collembolan from the Devonian period of Scotland. Available evidence indicates that it might have fed on plant juice obtained through punctured wounds (Strong et al., 1984). The characteristic spiny systems of Devonian plants were considered as defense against insect attack. By the end of Carboniferous period, all the modern groups of insects including Ephemeroptera, Orthoptera, ancestral Hemiptera and Mecoptera were well developed. Many of insect orders (Dictyoneurida, Michopterida and Diaphanopterida) that fluorished in the Carboniferous period are now extinct. These insects had beak-like, apparently piercing mouthparts, assumed to be reminiscent of the mouthparts of modern Hemiptera. These insects were believed to be phytophagous, feeding on the reproductive parts of fruits of Carboniferous and Permian plants. Insect pests have been categorized as key, major, minor, sporadic and potential pests based on their population and damaging capacity. These terms have been used rather loosely by different workers. In order to arrive at a definite and practicable concept, different categories of pests are defined in terms of the general equilibrium position (GEP), the economic injury level (ElL) and the damage boundary (DB). GEP is the mean value of pest density around which the pest population tends to fluctuate as changes occur in the biotic and. abiotic components of the environment without accompanied by a permanent modification in the composition of the environment. A permanent modification of any component of the environment may alter the GEP. The lowest level of injury where the damage can be measured is called the DB while the lowest number of insects that will cause economic damage is referred to as ElL.

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Key pest: These are the most severe and damaging pests. The GEP lies well above DB and ElL. Human intervention in the form of control measures may bring the population temporarily below the ElL but it rises back rapidly and repeated interventions (sprays) may be required to minimize damage. These pests present a persistent and perennial threat to our crops and are not being satisfactorily controlled with the available technology. There is need to lower their GEP below ElL by permanent modification of one or more components of the environment. Cotton bollworms, diamondback moth, gram pod borer, sugarcane borers and some vectors are the frequently occurring key pests. Major pest: Here the GEP is close to the ElL and in some cases both may essentially be at the same level. Thus the population crosses ElL quite frequently and repeated control measures are necessary but economic damage is avoided by timely interventions. Many of the important sucking pests like cotton jassid and whitefly, brown planthopper and leafhopper on rice, sugarcane whitefly and scale insect fall in this category. Rice stem borer, gall midge and leaf folder are also frequently major pests. Minor pest: The GEP in case of minor pests lies below both ElL and DB. Under favourable environmental conditions, the population may cross ElL and DB for usually a short interval. These pests are easily amenable to available control measures and a single application of insecticides is usually enough to prevent economic damage. Cotton stainers, grey weevil, thrips and mites; rice hispa and root weevil; sugarcane mealybugs, thrips and mites; and Spodoptera litura on oilseed and vegetable crops frequently occur as minor pests. Sporadic pest: The population of these pests' is usually negligible but in certain years under favourable environmental conditions, they appear in a virtually epidemic form crossing many times over DB and ElL. Under these conmditions, the pest has to be controlled by undertaking suitable management strategies. These pests are highly sensitive to abiotic conditions and once the favourable season is over, only a residual population survives. Many of the sporadic pests like white grubs, hairy caterpillars, cutworms and grasshoppers are polyphagous. But some oligophagous pests, e.g. sugarcane pyrilla may also be sporadic in nature. Potential pest: These insects are presently not causing any economic damage and, therefore, as such should not be labelled as pests. Their GEP lies below the DB and does not cross ElL even under favourable conditions. Any change (cropping pattern, cultural practices) in the ecosystem may, however, push their GEP higher and there is a danger of economic damage from these pests if control operations against the other categories of pests are undertaken in an indiscriminate manner. Under North Indian conditions, S. litura on cotton and sunflower, and armyworms on wheat are presently potential pests. A plant is neither susceptible to all the phytophagous insects nor any insect species is the pest of all the species of plants. Host range of a particular insect may be wide or narrow whereas some insects like locusts are feeders on all types of plants. However, such insects are usually not considered in host plant-insect interactions. Plant species which are fed upon by an insect are called host plants while those which are not fed at all are non-host plants. The inability of the insects to attack a non-host plant is termed immunity and such a plant is not considered a host of 92

that insect. The terms host plant and immunity exclude each other. Plants which are not fed at all are not generally considered for resistance and therefore, are classified as immune. A host plant can be resistant, more or less, but not totally immune. Any degree of host reaction short of immunity is, thus, resistance. Considering all the flora and fauna in nature and host plant-insect interactions, it can be concluded that immunity is the rule and susceptibility is an exception. In every plant species there exists a great deal of diversity with respect to the extent of damage done by an insect. Individual plants which show lesser damage are called resistant and those showing more damage are called susceptible. Thus, these terms are relative. Host plant resistance is the result of interactions between two biological entities, the plant and the insect under the influence of various environmental factors (Dhaliwal et al., 1993). References Dhaliwal, G.S., Dilawari, V.K. and Saini, R.S. 1993. Host plant resistance to insects : Basic concepts. In: G.S. Dhaliwal and V.K. Dilawari (eds.). Advances in Host Plant Resistance to Insects. Kalyani Publishers, New Delhi. pp. 1-30. Heinrichs, E.A. (ed.) 1988. Plant Stress-Insect Interactions. John Wilcy & Sons, New York, USA. Pradhan, S. 1983. Agricultural Entomology and Pest Control. Indian Council of Agricultural Research, New Delhi, India. Panda, N. and Khush, G.S. 1995. Host Plant Resistance to Insects. CAB International, Wallingford, UK. Paroda, R.S. and Arora, R.K. (eds.) 1991. Plant Genetic Resources – Conservation and Management Concepts and Approaches. International Board for Plant Genetic Resources, New Delhi, 392 pp.

Questions 1. a. b. c. d. 2. a. b. c. d. 3. a. b. c. d. 4.

When insects remain in dormant stage due to temperatures lower than the optimum, they are said to have undergone Hibernation Aestivation Quiscence None of the above When insects remain in dormant stage due to temperatures higher than the optimum, they are said to have undergone Hibernation Aestivation Quiscence None of the above The amount of energy transferred from one trophic level to other trophic level is: 90% 10% 50 % 100% The concept that no two species with identical ecological requirements can coexist in the

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a) b) c) d) 5. a) b) c) d) 6. a) b) c) d) 7. a. b. c. d. 8. a) b) c) d) 9. a) b) c) d) 10. a) b) c) d) 11. a) b) c) d) 12. a) b) c) d) 13. a)

same place, was proposed by H. G. Andrewartha D. Pimentel G. F. Gause L.C. Birch All the living organisms on earth interacting with the physical environment as a whole are referred to as the Biosphere Biome Ecosystem Community The physical and biological restraints realizing its biotic potential Biotic resistance Environmental resistance Carrying capacity Biological resistance The specific position of a species within a community including utilization of resources both in qualitative and quantitative terms is referred to as Niche Habitat Biome Ecotone The increase in concentration of a substance (usually a pesticide) in animal tissue as related to the animal's higher position in the food chain Bioaccumulation Biointensification Biolignification Biomagnification A population of a pest species that differs from other populations of the species in its ability to attack a particular cultivar Biotype (race) Biotypic Biotopic Biospecies An interaction where one of the organisms is harmed by the associated unaffected organisms is called Commensalism Amensalism Phoresy Mutualism The complete dependence of one organism over another is called Amensalism Mutualism Proto cooperation Commensalism Study of associations of organisms in relation to a particular area or habitat is Synecology Autecology Bioecology None of the above The response of insects to environmental rhythms of light and darkness is known as Photropic

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14.

15.

16.

17.

18.

b) Phototropism c) Photoperiodism d) None of the above The following is example of cannibalism in insects a) Helicoverpa armigera b) Praying mantids c) Ear wigs d) All of the above. Any .unit that includes all the with the physical environment a) Ecosystem b) Ecotype c) Ecological balance d) Ecological pyramid The type of diapause in enters diapause is called a) Obligate diapauses b) Facultative diapauses c) Saprophytic diapauses d) None of the above. Adult diapause is seen in which of the following insect a) Leptinotarsa decemlineata b) Epilachna corrupta c) Habrobracon brevicornis d) All the above. Pupal diapause is seen in Rice stem borer Red hairy caterpillar Castor hairy caterpillar All the above Many species live in the nests of ants and termites as guests are called as a) Inquilines b) Symbionts c) Parasites d) None of the above a) b) c) d)

19.

20. a) b) c) d)

Which one of the following is a reason for the population outbreaks? Absence of natural enemies Natality may be high Mortality is reduced All the above

Fill in the blanks with correct answer 1. 2. 3. 4. 5. 6.

The insects which are active during the dawn are called ............... The insects which are active during the dusk are called……………. A narrow band of temperature at which the normal physiological activitiesof insect takes place is called as …………… A physiological state of arrested metabolism, growth, and development that occurs at one stage in the life cycle under adverse environmental conditions is called ………… The measure of the innate ability of a population to survive and reproduce is called ………. The maximum population density in a given environment will support for a sustained period is called ……….

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7. 8. 9. 10. 11. 12. a) b) c) d)

When a major pest is suppressed by a tactic and a minor pest becomes a major pest then this condition is called as………… A species characterized by high reproductive rate and low survival rate is……….. A species characterized by low reproductive rate and high survival rate is………… The phenomenon of feeding on individuals of the same species is called as……….. ………….is the maximum number of organisms that a habitat can maintain at a specific time Match the term with their scientist who coined them: Ecology 1. Wheeler Ecosystem 2. Tansley Food chain 3. Elton Diapause 4. Ernst Haeckel

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USEFUL AND BENEFECIAL INSECTS LIKE HONEYBEES, LAC INSECT AND SILK WORMS SK Sharma Department of Entomology CCS HAU Hisar Apiculture is also known as bee-keeping. Why this name? ‗Apis‘ means bee. The scientific names of different species of honeybees begin with the generic name Apis. Apiculture or beekeeping is the art of caring for, and manipulating colonies of honeybee in large quantity, over and above their own requirement. Brief History The first evidence of this association came to light from the rock paintings made by primitive human. Thousands of years ago, Egyptian was well acquainted with bee keeping before the Christian era. In Rigveda, there are many references to bee and honey. Bee-keeping became a commercial proposition during the 19th century as a result of scientific research. Apiculture is a flourishing industry in many advanced countries like USA, Canada, Germany and Australia. Importance of bee keeping There are three main advantages of bee-keeping: (i) Provides honey - a valuable nutritional food (ii) Provides bees wax - which has many uses in industry (iii) Honey bees are excellent pollinating agents, thus increasing agricultural yields. In terms of actual value this advantage exceeds the other two. Species of honey bee There are four common species of honey bee under a single genus Apis: 1. Apis dorsata F. (The rock- bee)  This is the largest honeybee.  Builds single large open comb on high branches of trees and rocks.  Produces large quantity of honey, but this bee is difficult to domesticate.  This bee is ferocious, stings severely causing fever and sometimes even death. 2. Apis indica F. (The Indian bee)  Medium - sized  Hive consists of several parallel combs in dark places such as cavities of tree trunks, mud walls, earthen posts, etc.  This bee is not so ferocious and can be domesticated 3. Apis florea F. (The little bee)  small - sized  Builds single small combs in bushes, hedges, etc.  Honey yield is poor. 4. Apis mellifera L. (The European bee) 97

 Somewhat like the Indian bee (Apis indica).  This has been introducted in many parts of the world including India.  It is easily domesticated. The bee colony – various castes and their activities A honey bee colony has three castes (i) Queen – only one; functional female (ii) Workers – 20,000-30,000, sterile females (iii) Drones – a few only, functional males available prior to swarming. (i) Queen Bee Queen bee is the only perfectly developed female, that she has well developed ovaries and other organs of female reproductive system. She is largest in size. Its wings are smaller and are shriveled. Mouth parts for sucking food are shorter than that of workers. No wax glands. Live for about 3 - 4 years. Lay eggs at the rate of 800 - 1500 per day. Events in the life of queen bee Usually at the age of 7-10 days in her parent hive, after the old mother queen along with some workers had left for starting another hive, this new virgin queen goes out for marriage (nuptial) flights. The drones from the same hive chase her. This swarm may also be joined by drones (male bees) from other hives. Mating takes place, while flying, on an average, the queen mates with about six drones and then returns to the hive. The sperms she has received are enough for her whole life, and she never mates again. The queen has a control mechanism on the release of the sperms from the spermatheca (sperm store). She can lay two types of eggs: 1. Fertilized – eggs that produce females (either sterile workers or fertile females (new queens). 2. Unfertilized – eggs which produce drones. (ii) Worker bees Worker bees are imperfectly developed females. These are smaller than the queen. These have strong wings to fly. These have a large and efficient proboscis (mouth parts packed together like a thin tube) for sucking nectar. A well-developed sting is present. Hind legs have ―pollen basket‖ for collecting pollen. The workers have a life span of about 35 days. The different duties which they perform age-wise are as follows: Day 1-13 Activity inside the hive such as cleaning the hive, feeding the larvae, Day 14-17 comb building, Day 18-20 Guard duties at entrance to the hive Day 21- 35 Foraging, i.e. collecting the food (nectar and pollen from the surroundings) For foraging, some scout bees set out in the morning. On locating good sources of nectar (i.e. flowers) they return to their hive and perform characteristic movements (bee dances) at the comb. These dances communicate to the other worker bees the distance and the direction of the food source. This is how more and more worker bees are deployed in food gathering. The workers visit flower to flower, collect nectar and pollen and return to their own nest against taking clue from the position of Sun as well as by certain amount of memory and finally the smell of their own particular hive. A portion of the nest (hive) of the honey bee

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The bee dance In this dance the middle course of the dance communicates to the other bees the angle from the hive with reference to the sun. Taking a hint from this angle they have to fly to reach the food source. (iii) Drones Drones are the male bees produced from unfertilized eggs. Their production in the hive synchronizes with the production of the new (virgin) queens. At the age of 14-18 days the drones perform mating flight chasing the virgin queen in the air. Drones can live up to about 60 days, although they are stung and killed after the mating. The schematic representation of formation of different castes of bees is shown in Emergence of new Queen, and Swarming of the old one When the queen gets older (usually in the third year) her body gives out a chemical stimulus to the workers to construct a few rearing cells for queens. She places one fertilized egg in each of such brood cells. The larvae are fed on royal jelly (saliva of workers). They turn into pupae and then into queens. The first queen to emerge from the brood cells, kills the remaining ones. Now the old queen takes to swarming along with a mixture of workers of all ages, leaves the old hive to develop a colony at some new site. The new queen in the old hive takes to mating flight with the drones and returns to the same hive, as described earlier. Apiculture and commercial production of honey Bees produce honey and wax both of which are valuable and marketable commodities. (a) Indigenous methods of bee keeping Many villagers make (i) wall or fixed types of hives in rectangular spaces in the walls with a small hole or (ii) movable types of hives in wooden boxes or earthen pitchers. The traditional beekeepers catch clustered swarms from trees, bushes, etc and transfer them to the abovementioned spaces. After sometime when the honey is ready, the bees are driven away from the comb usually by smoking the hive. Then the comb is cut away and the honey is squeezed out through a piece of large meshed cloth. (b) Modern hives The modern beehive is made up of a series of square or oblong boxes without tops or bottoms, set one above the other. This hive has the floor at the bottom and a crown board at the top, and a roof over all. Inside these boxes, wooden frames are vertically hung parallel to each other. The wooden frames are filled with sheets of wax foundation on which the combs are built by the bees. The only entrance to the hive is below the large bottom box (brood chamber). The queen is usually confined to the brood chamber. The boxes termed ―supers‖ are used for storage of honey. The queen is prevented from going to the ―supers‖ by the ―queen excluder‖ that allows only the workers to move Catching a swarm You have already read what a swarm is. It is an old queen accompanied by huge population of workers flying to start a new hive. Swarms are collected from where they are settled. Some kind of a container is needed to collect the bees. The container is usually a straw basket (skep) with a lid. Hiving a Swarm It is the process in which the collected swarm is transferred to the hive to build up the colony and produce honey. It is operated in two ways:

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(i) Traditional method The hive is set up with brood chamber filled with its full number of frames. Each frame has a full sheet of foundation and there is a crown board with roof at the top. A sloping board with white sheet is set against the entrance of the hive. Bees in the skep (basket) are knocked out of it on to the slope. The instinct of the bees to move upwards onto the dark drives them onto the hive through the entrance. (ii) Quick method In this method the crown board of the hive is taken off, frames are also taken off and the entrance is closed. The skep is intimately united with the hive and the bees are poured into the brood chamber from the top. The frames containing the wax foundation are placed in the hive. The crown board is put back in its position and the entrance is opened. It must be seen that the queen enters the hive. Now, sugar syrup must be fed to the swarm, as this feeding will help the bees to settle down to work in their new home. Bee Pasturage The plants that yield nectar and pollen are collectively termed ―bee pasturage‖. The fruit trees, ornamental plants and forest trees comprise important bee pasturage. Nectar is the sweet secretion of the flowers. It is raw material for honey. Pollen provides the raw material necessary for the major food of the brood. Hive products A. Honey Honey is a food material for the bees and their larvae. Large quantities of honey are stored in the hive to meet the demands in scarcity. Chemically, honey is a viscous water solution of sugar. Its approximate composition in percentage is as follows: Water 13-20 Fructose 40-50 Glucose 2-3 Minerals Traces Vitamins (minute quantities) (B1, B2, C) Composition of honey and its different flavours depend on the kinds of flowers from which the nectar is collected. Nectar is sucked from flowers and mixed with saliva. It is swallowed into a special region of the gut called honey stomach. Nectar is a disaccharide (sucrose) it is hydrolysed by the salivary amylase to produce monosaccharides (fructose and glucose). Inside the hive the workers regurgitate the processed nectar. The honey thus produced is still very dilute. After placing this honey onto the storage cells of the hive the bees ―fan‖ with their wings to evaporate the excess water and bring the honey to its required concentration. Extraction of honey from the combs is done by centrifugation. Uses of Honey Some uses of honey are as follows – Food: Honey is a nutritious food, rich in energy and vitamins. – Medicines: It is used as a carrier in ayurvedic and unani medicines. It acts as a laxative and prevents cold, cough and fever. – It is used in religious ceremonies. – It goes in the making of alcoholic drinks and beauty lotions. – Another important use is in scientific research for making bacterial cultures. – It is also utilized for making poison baits for certain insect pests. 100

Purity Standards There is no ready method to test the purity of honey by the customers. Homogenous granulation is a probable sign of its purity. Otherwise there are laboratory methods for testing (test for monosaccharides). B. Beeswax Beeswax is secreted by the wax glands located on the underside of the last four abdominal segments (4th to 7th) of the worker bee. This wax is used in constructing bee combs in which the colony of the bees develops. Uses of beeswax Some uses are as follows: – making of candles (the modern candles are made of paraffin wax, a petroleumproduct); – making pharmaceutical preparations; – preparation of varnishes and paints; – Water proofing and waxing of threads; and – Formation of comb foundation (wax foundation in apiaries). LAC CULTURE INTRODUCTION Members of two families of Hemiptera, namely, Lacciferidae and Tachardinidae secrete lac over their bodies for protection. Lac Insect belongs Laccifer of superfamily Coccoidea of order Hemiptera. In all 22 species have been recorded under the genus Laccifer in Indian subcontinent. India is still being regarded as the principal lac producing country of the world. Burma went into lac trading since sixteenth century. Lac culture in China probably dates back to 4000 years and they use lac for dyeing silk and leather goods. India produces about 65% of the world‘s total output. Bihar and Jharkhand account for 40% of India‘s total production of lac. HOSTS Plants such as, Zizyphus mauritiana, Z. jujuba, Butea monosperma, Schleichera oleosa, Acacia arabica, A catechu, Cajanus cajan, Ficus benghalensis, F. cunia, and F. religiosa are common hosts of the lac insect Laccifer (=Tachardia) lacca. BIOLOGY Laccifer lacca, (=Tachardia lacca) is the commercially cultured lac insect. It is mainly cultured in India and Bangladesh on the host plants such as ber, Zizyphus mauritiana, palas, Butea monosperma and kusum, Schleichera oleosa. Female insect is viviparous, producing about 1000 nymphs, deep red in colour with black eyes. The larvae settle down on a suitable place of the host plant gregariously. A day or two after settlement, the larvae start secreting lac all around the body except on the rostrum, spiracles and on the tip of abdomen. Thus it gets encased in a cell of lac which gradually increases in size along with the increase in size of the insect. The insect moults twice before reaching maturity. The male larvae produce elongated lac cells while the females produce oval cells After the first moult larvae lose their legs, antennae and eyes and become bag-like. After the 3rd moult, the larvae pass on to a pseudo-pupal stage. Males emerge and copulate with the females and die. The female larvae never regain appendages and continue to remain under the lac cell, become adults and reproduce. As the lac insects remain close together, lac secretion from adjacent cells coalesces with each other and forms a continuous encrustation on the tree branch.

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LAC CULTIVATION Lac culture involves two important steps: (i) inoculation, and (ii) cropping. Inoculation can be carried out through artificial infection of tender branches by brood lac stick obtained form mature lac trees immediately after harvesting. In this process, the brood lac sticks are tied in bundles of 2 or 3 sticks on the branches of the host tree, allowing maximum contact with the branches. There are four seasons of lac cultivation and according to the Hindi calendar, they have been named as Kartiki, Aghani, Baisakhi, and Jethwi. The crop period, from inoculation to harvesting, for Kartiki, ranges from July to November, for Aghani, from July to February, Baisakhi, from November to July, and Jethwi, from February to July. When young shoots come up on branches, the brood sticks are tied adjacent to the growing tender branches in a way so that maximum contact between shoots takes place. Within a week or two the larvae emerge and settle down on tender shoots. PROCESSING OF LAC Lac encrustations are removed from the twigs of host plants by scraping. The raw lac thus obtained is known as scraped lac or stick lac. Stick lac is crushed into small grains, sieved, washed with mild alkaline water and dried. This semi-refined product, called seed lac or grain lac or Chowrie, which is further refined by a system of hot melting, filtration and stretching into thin sheets which are subsequently broken into brittle flakes called shellac. Alternatively the purified lac resin can be in the form of circular discs called button lac. If a solvent process is used to purify the raw lac, de-waxed, decolorized lac can be obtained as the end product. The normally amber coloured resin can also be bleached with sodium hypochlorite to obtain bleached lac, which is white in colour. Bleached lac has specialised demand for coating medicinal tablets, confectioneries etc. India is the principal lac producing country of the world, producing approximately 18,000 metric tonnes of raw lac annually. About 85% of the country‘s production is exported to various countries. The USA, Germany and Egypt are some of the major lac importing countries of the world. USES OF LAC The various applications of lac can be summarized as follows: Lac resin is used in food processing industry; cosmetics and toiletries industry; varnish and printing industry; coating of fruits and vegetables; electrical industry; leather industry; adhesive industry; pharmaceutical industry; perfumery industry; miscellaneous applications. Lac dye (erythrolaccin) has been used in India as a skin cosmetic and dye for wool and silk. In China it is a traditional dye for leather goods. The use of lac for dye has been supplanted by synthetic dyes. It is used in medicine to protect liver and to fight obesity. Lac is used in food, confectionery and beverages industry and textile industry. Lac wax is used in polishes for shoe, floor, car polishes etc. It is used in electric insulations, lamination of papers, hat proofing and coating of pictures and fossils. Lac is used for manufacture of tailors chalks, crayons, bottle sealers, lipsticks, enamels, printing inks, gramophone records and in fireworks. NATURAL ENEMIES OF LAC Predators: Two moth predators cause a lot of damage to lac.

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1. Eublemma amabilis. The larva is dirty white in colour and tunnels through the lac encrustation and feeds on larvae and adults. It pupates within the tunnel and adults after emerging lay their eggs near the lac encrustation. 2. Holcocera pulverea. The damage by the brownish larva is similar to the above species. Pupa is slightly bigger and yellowish-brown. Parasites: The following insects are parasitic on lac insect. Paraecthrodryinus clavicornis; Erencyrtus dewitzi; Tachardiaephagus tachardiae; Eupelmus tachardiae; Tetrasticus purpurens. The above natural enemies can be controlled by maintaining healthy cultures and by enclosing the brood lac sticks in wire mesh before inoculation so that natural enemies are not able to emerge and cause re-infestation. Sericulture Importance and Scope of Sericulture The word Sericulture is derived from the Greek word ‗sericos‘ meaning silk and the English ‗culture‘ meaning rearing. Sericulture refers to the conscious mass scale rearing of silk producing organisms in order to obtain silk from them. Mulberry sericulture involves the cultivation of mulberry to produce leaf, rearing of silkworm to convert leaf to cocoon, reeling of the cocoon to obtain silk yarn. Silk producing organism Silk is a fibrous protein of animal origin. Nearly 400-500 species are known to produce silk but only very few are commercially exploited. Based on the organism producing it, silk is classified into Insect Silk and Non-Insect Silk. Insect silk is commercially more important. Majority of silk producing insects belong to the Order: Lepidoptera Super family: Bombycoidea Family: Bombycidae Nearly 95% of commercial insect silk comes from the mulberry silkworm Bombyx mori and is known as mulberry silk. Commercial silk from all other sources is collectively called Non-mulberry silk. The major non-mulberry silkworms include: A) TASAR silkworms i) Indian Tropical Tasar ii) Indian Temperate Tasar iii) Chinese Tasar iv) Japanese Tasar B) MUGA Silkworm C) ERI Silkworm D) ANAPHE Silkworm E) GONOMETA Silkworm F) FAGARA Silkworm G) COAN Silkworm H) Spiders I) MUSSEL 103

Other lepidopterans like Moon moth (Actias selene), Cashew caterpillar (Cricula trifenestrata), Gregarious mango caterpillar (Cricula sp.), Cecropia moth (Philosamia cecropia) are non-commercial sericigenous insects. Use of silk 1) Silk is a natural fibre used in textiles. It is soft, smooth, lustrous and holds a prestigious place among textile fibres. 2) Silk may be sold and exported as raw silk yarn itself. It may also be woven into fabrics and sold as such or readymade garments. 3) Various articles like ties, scarves, soles, shawls, furnishings, carpet, silk fibres, socks etc. are made and marketed. 4) Variety of fabrics like dupions, plain silk, deluxe, satins, chiffon, chinnons, crape and brocades are woven. 5) Cosy furnishing materials are made. 6) Spun silk fabrics are made from silk spun from the silk wastes generated during reeling of silk cocoons. Waste silk also have a good export market. 7) Tasar silk fabrics in exotic designs are in good demand for export. 8) Golden Muga silk is consumed in domestic market in the form of sarees and dress material. 9) Fine quality Eri spun silk is used for dress materials and the coarse variety for making bed sheets shawls and quilts. 10) From trimoulters, a special kind of silk is prepared which is used as package material in pencil industry and for making talcum powder puffs. 11) Silk is used as raw material in preparing sound free gears for use in making precision machinery. 12) Denier silk is used in tyre manufacturing. 13) Parachute is made with denier silk fibre. 14) Cosy and soft sky jackets, comforters, and sleeping bags are also made. 15) A fibre of uniform thickness is made from silk glands and is used in surgery. As this fibre is a protein and auto-absorbable and need no removal after healing of wounds due to surgery. 16) Silk grafts have also been used successfully to replace cut arteries. 17) Silkworms are used in insect-physiology and genetic engineering research studies. 18) Developing countries are taking up sericulture because it can generate employment and can earn valuable foreign exchange. Silk production in the world About twenty nine countries are practicing sericulture but most of them started recently. The major silk producing countries are China, Japan, India, former USSR, South Korea and Brazil. Silk production has gone down in some countries like Japan and South Korea but has gone up in countries like India and Brazil. Countries like Vietnam, Philippines, Indonesia, Iran, Sri Lanka, Bangladesh, Afghanistan, Malaysia, Madagascar and Pakistan have now found a place in the sericulture map of the world. Sericulture in India In the pre-British period it flourished in the states of Bengal, Mysore and Kashmir. Foundation for the Modern Indian Silk Industry was laid during the British period and sericulture spread to the south also. At this time, it spread from Kashmir to the mainstream of India (other states). Separate sericulture departments were created in Karnataka in 1911, Madras in 1919, formation of Mysore Silk Association in 1927, Mysore Silk Weaving Factory (1932), Mysore 104

Spun Silks (1936), Silk Conditioning and Testing House at Mysore in 1942, Sericulture Research Station at Berhampore (1943) which helped the rapid progress in sericulture industry of India. Sericulture after independence It was soon after independence that the Central Silk Board was established at Bangalore. The Central Silk Board has now grown into a big organization. For coordination between state and central agencies, it has five regional offices at New Delhi, Mumbai, Calcutta, Srinagar and Bangalore and seven regional development offices at Bhubaneswar, Guwahati, Lucknow, Hyderabad, Maldaa, Chennai and Patna. For mulberry sericulture there are 2 Central Sericulture Research and Training Institutes one at Mysore and others at Behrampore. For non-mulberry sericulture, there are 4 institutes 1) The Central Tasar Research and Training Institute, Ranchi (Jharkhand), 2) The Central Muga Research Institute, Jorhat (Assam), 3) The Central Eri Research Institute, Mandhipathar and 4) The Central Eri and Muga Research Station, Titabar (Assam). These institutes have Regional Sericulture Research Stations (RSRS) at Chamrajnagar (Bangalore) in Karnataka, Salem and Coonoor (Tamil Nadu), Anantapur (Andhra Pradesh), Tiruvananthapuram (Kerala), Kalimpong (West Bengal), Ranchi (Jharkhand), Dehradun (Uttra Khand)), Jorhat (Assam), Dhule (Maharashtra), Koraput (Orissa) and Pampore (Jammu & Kashmir). Research Institutes dealing research and development work in sericulture 1) Central Sericulture Research and Training Institute at Mysore and Berhampore. 2) The National Silkworm Seed Project, Bangalore (1981) 3) The Central Silk Technology Research Institute, Bangalore (1983) 4) The Silkworm Seed Technology Laboratory , Bangalore (1993) 5) The Biotech Laboratory (1993) Future scope 1) Sericulture requires mulberry cultivation. Mulberry is a hardy, perennial plant and can be grown in wide range of soil conditions and also in rainfed conditions. It is suited for Indian conditions where large waste lands (unsuitable for other plants) are lying. Indian farmers are now shifting for mulberry cultivation as the income is more than other crops. Mulberry sprouts throughout the year in India and quality leaves can be harvested. 2) Sericulture is a labour-intensive industry. High cost of labour and non-availability of labour has lead reduction in silk production in Japan. In India, there is no problem of labour. 3) Sericulture does not require great skill. So ideally suitable for unskilled labour families, women, handicapped and children. Many unemployed educated youths are taking up sericulture under the self-employment schemes by government. 4) One hectare mulberry creates remunerative employment for 12-13 persons throughout the year. 5) It is ideal sideline activity for rural people engaged in agriculture. Income generation is within one month. 6) Sericulture as main activity also ensures regular income throughout the year. 7) An ideal cottage industry requiring low initial investment, village made simple equipments and simply constructed rearing houses. 8) Govt. is providing subsidy on material required for sericulture. State governments have introduced a number of schemes for giving financial, technical and material assistance for sericulture. 9) Banks and other funding agencies provide loan facilities for sericulture.

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10) Nothing in sericulture is a waste. Unfed mulberry twigs can be used as fuel, the litter as fertilizer or for biogas production Defective cocoons and reeling wastes can also be used for spun silk industry. Silkworms and their Races Silkworms can be grouped into mulberry silkworms and non-mulberry silkworms. A) Mulberry Silkworm (Bombyx mori) Order: Lepiodeptera Class: Insecta Superfamily: Bomycoidea Family: Bomycidae The mulberry silk worm is domesticated throughout the world. It is not known to occur in the wild state. This silk worm undergoes complete metamorphosis and has four stages in its life cycle. i) Egg ii) Larva iii) Pupa iv) Adult Duration of each stage varies with different races, climatic conditions and quality of food. Egg stage varies depending upon - diapausing or non-diapausing Diapausing eggs under natural conditions remain dormant for months before hatching. It can be broken by acid treatment. Non-diapausing eggs normally complete their embryonic development in 9 to 12 days and hatch into larvae. Larvae may have 4, 5 or 6 instars. Most of the races have 5 instars. The final instar larva after full growth, empties its gut stop feeding and spins the cocoon of silk around itself. At this stage it is called a prepupa. After spinning it mounts into the pupa inside the cocoon. Pupa does not feed. Adult emerge by breaking cocoon. Adults are non feeding and short lived. Based on number of generations completed in a year they can be classified as under: Univoltine - complete one generation in a year Bivoltine - complete two generations in a year Multivoltine - complete more than two generations in a year B) Non-mulberry silkworms 1) TASAR silkworm This is most important non-mulberry silkworm. The TASAR cocoons are large, thick and pedunculate. They are made of a single unbroken filament and hence are reelable Four important kinds are: a) Indian tropical TASAR - Multivoltine (Antheraea mylitta) are found in tropical India. Cocoons are grey white, tough and pedunculate. It is polyphagous and host plants are primary. asan (Terminalia tomentosa) arjun (Terminalin arjuna) Secondary host plants are - Shorea robusta, Zizyphus sp. b) Indian temperate TASAR (Indian oak TASAR) (Antheraea proylei) It is a hybrid silkworm. Cocoons are grey white in colour. Host Oak - Quercus sp. c) Chinese TASAR (A. pernyi): Occcurs in China and also in former USSR. It is largest silkworm. Cocoons are grey brown. Silk reeled from it is used for making embroidery threads and also for weaving fabrics. Feeds on oak - Quercus sp

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d) Japanese TASAR (A. yamamai): Mainly found in Japan. The silk is greenish tinted and used for fabrics and embroidery work. Host - oak 2) MUGA silkworm (A. assamensis): Multivoltine, cocoons are weakly pedunculate, large and strong. They are smaller than TASAR cocoons and are reelable. This occurs only in India, in Brahmaputra valley and hills of Assam. Used for outdoor rearing by tribal peoples. Indoor rearing has also been started. Hosts - Som and Soalu trees 3) ERI silkworm a) Wild ERI silkworm/Ailanthus silkworm (Philasamia cyntia): It is wild, bivoltine and no indoor rearing. Found in Europe, Africa and Eastern United States. b) Castor silkworm (P. ricini): Multivoltine and polyphagous: Cocoons are very weakly pedunculate and are nonreelable because open at one end. Cocoons are white or brick-red. Hosts: Castor, kesseru and tapioca 4) ANAPHE silkworm (Anaphe sp.): Found in Southern and Central Africa. Univoltine and polyphagous. This form collective cocoons. The silk is more elastic and stronger than mulberry silk. 5) GONOMETA silkworm (Gonometa sp.): Widely distributed throughout the African savanna. It is polyphagous. Cocoons are elongated, ellipsoidal in shape, their shell is hard. Cocoons are unreelable and silk is obtained by spinning. The sericin content of the cocoons of this silkworm is high (45-55%) compared to 25-30% in mulberry silkworm. Maximum cocoons are found on Acacia sp. particularly A. tortieis which is most widely distributed in Bostwana. 6) FAGARA silkworm: Found in China and Sudan. FAGARA silkworm belongs to genus Attacus (include 13 species). Giant silk moth, Attacus atlas is important commercially. Cocoons are light brown in colour and penuncluate. 7) COAN silkworm/Syrian silkworm (Pachypasu sp.): Extensively cultivated in Europe until the introduction of Chinese silkworm Bomhyx mori, but also occurs in Mauritiana and Morocco. P. otus and P. lineosa on commercially used. Cocoons are white in colour. Yield is very little. Fagara and coan silks are inferior to the other non-mulberry silks of Africa. Due to high cost of production they are not used much in textiles. 8) Spiders: Three species of spiders namely Nephila madagascarensis, Miranda aurentia, Epthira sp. are used for silk production. Webs of spider is made of silk. And called spider silk. The silk is not only soft and fine but strong and elastic. Due to very low production not used in textiles. 9) MUSSEL: The byssus thread of the mussel Pinna squamosa are spun into a silk called fish wool in Italy. Races of silkworms Mulberry silkworm has a large number of genetically different races. Being useful insect many countries are evolving new varieties or races. In Japan, more than 2000 races are maintained. In India, about 200 races are maintained. A) Races based on number of larval moults On the basis of number of moults which the silkworm undergo during larval life, it has three races: Tri - moulters 107

Tetra - moulters Penta - moulters Most of commercially exploited races are tetra moulters with 5 larval instars. B) Based on voltinism Voltinism: Refers to number of broods raised per year. Based on voltinism 3 types of races are: 1) Univoltine: Univoltine races produce only one generation per year. Eggs laid remain in diapause condition till next spring. Larvae of univoltine are very sensitive to temperature and other environmental conditions. Diapause can be broken artificially but larvae cannot be reared in summer and autumn. Larval period is long. The races which Europe have are all univoltines. Their cocoons are commercially very superior. 2) Bivoltines: These have 2 generations per year. Ist generation adults developing from eggs hatched in spring lay non-diapausing eggs. Second generation adults developing form these eggs, lay eggs which go in dormancy till next spring. The larval duration is as long as univoltines. Larvae are robust and tolerate environmental changes. They can be reared in summer and autumn. Japanese and Chinese races have both univoltine and biovoltine. Cocoons are commercially superior. 3) Multivoltines or Polyvoltines: These have more than 3 generations per year. Larvae can tolerate environmental changes and its duration is short. Larvae and cocoons are small in size and they are commercially poor. Adults lay non-dispausing eggs. These are found in tropical conditions. Bivoltine races of mulberry silkworm produce white cocoons Multivoltine races of mulberry silkworm produce greenish or golden-yellow cocoons Developmental duration of univoltine, bivoltine- and multivoltine races of B. mori Stage Embryonic period Larva Pupa Adult C)

Univoltine 11-14 days 24-26 days 12-15 days 6-12 days

Bivoltine 11-14 days 24-26 days 12-15 days 6-10 days

Multivoltine 9-12 days 20-24 days 10-12 days 3-4 days

Races based on place of origin Based on place of origin mulberry silk worm races are Japanese, Chinese, European and

Indian. They can be distinguished from each other on the basis of morphological, biological and commercial characters. Morphological characters Character Voltinism Colour Larval size Larval health Larval duration

Japanese Uni & bivoltine Pale and yellow Small Robust Long

Chinese Uni/bi/multivoltine Green Large Robust Short

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European Univoltine Slate Large Weak Long

Indian Multivoltine Purplish yellow Small Robust Short

Commercial Characters Character Japanese Chinese Cocoon size Large Large Cocoon colour White, yellow or White, goldengreen yellow, flesh coloured or red Reelability Good Good Cocoon 2.39 g 2.25 g for bi/uni weight 1.1-1.2 g for multivoltine races Silk yield 19% 16% for uni/bivoltine 10-11% for multivaltine races

Questions 1.

2.

3.

Species of honeybees in the world: i) Apis dorsata F. (Wilq) ii) A.cerana F.(Domesticated) iii) A.florea F. (Wild) iv) A.mellifera L.(Domesticated) v) A.andreniformis (wild) vi) A.koschenovki .(Domesticated) vii) A.laboriosa(Wild) Essential beekeeping equipments: i) Longstroth bee hive ii) Honey extractor iii) Bee veil iv) Smoker v) Uncapping knife vi) Uncapping tray vii) Comb foundation viii) Comb foundation sheet ix) Queen excluder x) Queen cage xi) Hive fool xii) Queen cell protector Hive products i) Honey ii) Wax iii) Pollen iv) Royal jelly v) Bee venom vi) Bee brood 109

European Large White or flesh

Indian Small Green, yellow

Good 2.0-2.4 g

Poor 0.9 g

20%

6%

white,

4.

5.

6.

7.

8.

9.

10.

Major role of honey bees in crops Pollination and helps in increasing the crop yield. Flowers characteristics favour crops pollination: i) Unisexuality ii) Heterotype iii) Protogyny iv) Protoandry v) Physiological incompatibility Natural enemies of honeybees i) Birds green bee eater, kingcrow ii) Wasp Vespa orientalis, V. basalis, V. magnifora etc. iii) Wax moth – Galleriamellonella, Achrora griesella iv) Ants – Monorum spp. v) Mites – Acarapis woodi vi) Varroa destructor vii) Tropilaelaps clarae Bee diseases i) Bacterial AFB ii) EFB iii) Fungal chalk brood iv) Store brood v) Viral sac brood vi) Thai sac brood vii) Protozoan Nosema sp. Seasonal management i) Thermoregulation clustering (winter) Temp. 34 to 35oC Farming (summer) ii) Artificial feeding nectar substitute – Sugar syrup 50% Pollen substitute – soybean p iii) Provision of water near the apiary iv) Put these hive in shade during summer & sunder sunshine in work v) Maintain strong colonies vi) Unite weak colonies vii) Extract honey at frequent interval to provide space viii) Raise frame during honey flow season ix) Replace old queen during Feb.-March x) During rainy season protect the colonies from ants, & was moth & wasps Treatment books in the field of apiculture: i) Beekeeping in India by Sardar Singh (1962) ii) Hive and the honeybee by Dalant & Sons iii) Perspective in Indian Apiculture – R.C.Mishra iv) By O.P.Abrol v) By D.P.Abrol Selection of apiary site: 110

i) ii) iii) iv) v) 11.

12.

13.

Plenty of bee flora Water source Away from road/highways Away from pesticidal prove area Away from mobile tower/electrical sub station Pesticidal poisoning: Neonectonoide insecticides – highly toxic to bees – dust – WP – EC – Granules Apply insecticide when bees are not foraging in the field Spr;ay in the evening Bee flora: i) Brassica ii) Eucalyptus iii) Sunflower iv) Shisham Silk worm and sericulture: i) The largest producer of silk in the world is CHINA ii) The largest consumer of silk in the world is INDIA iii) The only country that produces all the five commercial type of silk is INDIA iv) Eri-silkworm is reared on CASTOR v) India has monopoly in the production of Miga silk vi) Mega silkworm belongs to the family saturniidae vii) Silkworm (bombyx mori) is monophagous viii) The silk that is reared in indoors – Mulbery ans Eri. ix) The silk that is reared outdoors (natural conditions) Tasar and Muga x) To produce 1 kg of raw silk, the quantity of cocoons required in 7 to 8 kg. xi) Which state in India is leading producer of mulberry silk – Karnataka xii) Which state in India is leading producer of non-bulbery silk – Assam xiii) Of the total silk produced in the country, 90% is produced from Maltivoltine xiv) The disease of silk worms is managed only through mother moth examination – Pebrine. xv) Indian sericulture is mostly multivoltine

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Foundation Course Manual on ICAR-JRF (PGS) in Agriculture – Entomology and Nematology Eds SS Yadav, KS Bangarwa, Surender S Dhankhar and RK Pannu CCS HAU, Hisar 2014, pp 112-122

MAJOR INSECT-PESTS OF SUGARCANE, COTTON, MAIZE AND THEIR MANAGEMENT Sunita Yadav Department of Entomology CCS HAU Hisar INSECT-PESTS OF SUGARCANE S Insect-pest Nature of Damage No. Borers Early shoot borer Eggs are laid on underside of leaf sheath. Larvae cut the 1. Chilo infuscatellus growing shoot resulting into dead heart formation in 1-3 Pyralidae: Lepidoptera month old crop which can be pulled out easily and emits an offensive odour. Bore holes are at the base just above the ground level. Top borer First two broods attack the young plants resulting into 2. Scirpophaga excerptalis formation of dead heart which cannot be pulled out easily. Crambidae: Lepidoptera There are parallel rows of shot holes in the emerging leaves and red tunnels in the midribs of leaves. Subsequent broods attack the terminal portion of the grown up canes resulting into formation of side shoots called as bunchy top. It passes winter as full grown larva in cane tops. Stalk /tarai borer Insect first appear on ratoon crop. Larva bore into the cane 3. C. auricilius and feed on internal content by boring into one internode Crambidae: Lepidoptera after another and by moving from plant to plant. Soft varieties, heavily manured and waterlogged fields suffer more. Internode borer Attack the crop at late stage. There is presence of borer 4. C. sacchariphagus indicus holes with fresh excreta in the nodal region and reddening Crambidae: Lepidoptera of affected tissues. Root borer Caterpillars eat inside the lower stem. Damage is 5. Emmalocera depresella characterized by dried-up central shoot known as dead Crambidae: Lepidoptera heart, which cannot be pulled out easily. Gurdaspur borer The young larvae feed gregariously in the top portion of 6. Acigona steniella the canes by making spiral galleries and later by boring Crambidae: Lepidoptera into the cane. Dried cane tops are seen in the field.

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Sucking pests Black bug 7. Cavelerius excavatus Lygaeidae: Hemiptera Whitefly 8. Aleurolobus barodensis Aleurodidae: Homoptera

9.

Scale insect Melanaspis glomerata Diaspididae: Homoptera

10.

Mealy bug Saccharicocus sacchari Pseudococcidae: Hemiptera

11.

Leaf hopper Pyrilla perpusilla Lophopidae: Hemiptera

12.

White wooly aphid Ceratovacuna lanigera Aphididae: Homoptera

Subterranean pests Termite 13. Microtermes obesi Odontotermes obesus Termitidae: Isoptera 14.

White grub Holotrichia consanguinea Melolonthidae: Coleoptera

Both nymphs and adults suck cell sap from the central whorl in young plant and within leaf sheath on grown up plants. Attacked leaves become paler and show holes. Only nymphs cause damage by sucking sap from the leaves, thus causing characteristic yellow streaks. Leaves become dry and plants become stunted in severe infestation. Honeydew secretion leads to development of sooty mould. Insect feed on the stem parenchyma, thus prevent the accumulation of sucrose in the cane. Infested crop loses its vigour, canes shrivel, growth is stunted and the internodal length is reduced very much. Nymphs and adults suck sap from the cane by sticking to the nodes under leaf sheath and befoul them by mealy secretions and honeydew. Sooty moulds develops giving blackish appearance to the canes, vigor of the plant is reduced. Nymphs and adults suck sap from leaves, infested plants loose vigor and become shrunken. Honeydew secretion leads to development of sooty mould. The cane juice become high in glucose and turns insipid. Cornicles are atrophied. Nymphs and adults congregate in groups and suck the sap from leaves. Sooty mould develops due to honey dew secretion. There is white chalk powder coating on the ground and leaves. Poor germination of setts. Characteristics semicircular feeding marks on the leaves in the standing crop. Entire shoot dries up and can be pulled out easily. Setts hollow inside and may be filled with soil. Cane collapses if disturbed and rind filled with mud. Become active with onset of summer showers and grubs feed on live roots as a result the cane dries up. Complete one generation in a year.

Management  Monitoring of borers by the installation of pheromone traps @ 10/ha and white grub by installation of light traps.  Adopting cultural practices like deep summer ploughing, proper crop rotation, growing resistant or tolerant varieties, planting healthy setts, timely sowing in deep furrows (20 cm depth), using well rotten FYM.

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 Avoiding application of high nitrogen fertilizers to minimize pyrilla, wooly aphid and stalk borer attack.  Irrigation at close intervals to minimize termites and early shoot borer incidence.  Detrashing of canes to reduce scale insects, mealy bug, wooly aphid and stalk bore attack.  Rouging of infested plants  Propping the canes to prevent lodging and to reduce the damage by stalk borer and rodents.  Clipping of leaves bearing eggs masses of top borer, Gurdaspur borer and pyrilla  Removal of dead hearts of early shoot borer and top borer. Removal and destruction of infested canes.  Intercropping with cow pea and black gram to conserve natural enemies  Soil incorporation of Metarrhizium anisopliae 2.5 x 1010 spores / m3 for the management of white grub  Spray granulosis virus (GV) @ 250 LE/ha against shoot borer.  Release of egg parasitoids, Trichogramma chilonis @ 1,00,000/ha against early shoot borer  Release of Sturmiopsis inference@ 125 adult females/ha in coastal region of Tamil Nadu against early shoot borer  Release of pre-pupal parasitoid, Isotima javensis against top borer and Lepidopteran predator Dipha aphidvora against wooly aphid.  Release of parasitoid Epiricania melanoleuca @ 4000-5000 coccons or 4-5 lakh eggs/ha for the management of pyrilla  Release of Pharoscynmus horni @ 1500 adults beetles or grubs against sugarcane scale insect.  Release of Cotesia flavipes @ 500 mated females at weekly interval till Nov. for the management of stalk borer, Gurdaspur borer, root borer and internode borer.  Need based judicious and safe application of insecticides.  Application of chlorpyriphos 20 EC at the time of planting for the management of termites, white grub and early shoot borer.  Application of phorate 10 G or carbofuran 3G granules along the furrows for the control of top borer.  Application of metasystox or dimethoate for the management of sucking pests. INSECT-PESTS OF COTTON S No. Insect-pest Nature of Damage Boll worm Complex Spotted bollworm Adult of E. vitella has pale whitish fore wings with a 1. Earias vittella broad greenish band in the middle while E. insulana has Noctuidae: Lepidoptera completely green forewings. The caterpillar damage by Spiny bollworm boring into the growing shoot, flower buds, squares and Earias insulana bolls. There is drying and drooping of terminal shoots Noctuidae: Lepidoptera during pre–flowering stage and flaring up of bracts during square and young boll formation stage. Heavy shedding of squares and young bolls, premature opening of bolls. 114

American bollworm Larvae feed voraciously on leaves and flowers initially. Helicoverpa armigera Later on they bore in to the square/bolls and seeds and start Noctuidae: Lepidoptera feeding by thrusting their heads alone inside and leaving the rest of the body outside. Bolls show regular, circular bore holes. Pink bollworm Freshly emerged larvae bore into flower buds, flowers and 3. Pectinophora gossypiella bolls. The holes of entry close down by excreta of larvae Gelechiidae: Lepidoptera but larvae continue feeding inside the seed kernels. They cut window holes (interlocular burrowing) in the two adjoining seeds thereby forming "double seeds". The flowers do not open and give rosette appearance. The attacked buds and immature bolls drop off. Lint is destroyed; ginning percentage and oil content are impaired. Hibernate as full grown larvae in double seed. Tobacco caterpillar First instar larvae feed gregariously on the leaf by 4. Spodoptera litura scrapping the epidermal layer, leaving the skeleton of Noctuidae: Lepidoptera veins. Grown up larvae move to other leaves and feed by making small holes thus completely skeltonizing the plant. Sucking pests Leafhoppers/Jassids Insect lay eggs inside leaf veins. Both adults and nymphs 5. Amrasca devastans suck sap from the underside of the leaves and inject toxins Cicadellidae: Hemiptera due to which leaves turn pale and then rust red. There is marginal downward rolling, cupping, yellowing, browning, bronzing and drying of cotton leaves thus giving hopper burn like symptoms Whitefly Nymphs and adults suck plant sap resulting into loss in 6. Bemisia tabaci plant vitality and premature defoliation. Sooty mould Aleyrodidae: Hemiptera develops due to honeydew secretion. The insects transmit leaf curl virus (CLCV) disease. Cotton aphid Both adults and nymphs suck sap from the tender leaves, 7. Aphis gossypii twigs and buds. There is leaf crumbling and curling. They Aphididae: Hemiptera excrete honeydew which encourages development of sooty mold. Cotton thrips Both nymph and adult lacerate the tissue and suck the 8. Thrips tabaci oozing out sap from the upper and lower surface of leaves Scirtothrips dorsalis and in cases of severe infestation they curl up and become Thripida: Thysanoptera crumbled. Silvery sheen on the lower surface can be seen in early stages of attack. Red cotton bug/ cotton Adult lay eggs in the soil. Both nymphs and adults suck the 9. stainer sap from developing green bolls and stain the lint. They Dysdercus cingulatus stain the lint with excreta and body juices as they get Pyrrhocoridae: Hemiptera crushed in ginning factory. The bugs are gregarious in habit. Attacked seeds loose viability and fiber stained due to bacterial (Nematospora gossypii) growth. 2.

115

10.

11.

Dusky cotton bug Oxycarenus hyalinipennis Lygaeidae: Hemiptera Mealy bug Phenococcus solenopsis Pseudococcidae: Hemiptera

Foliage feeders and Other Green semilooper 12. Anomis flava Cotton semilooper Tarache notabilis Noctuidae: Lepidoptera Cotton leaf roller 13. Sylepta derogate Pyralidae: Lepidoptera Cotton stem weevil 14. Pempherulus affinis Curculionidae: Coleoptera Cotton grey weevil 15. Myllocerus undecimpustulatus Curculionidae: Coleoptera

Both nymphs and adults suck the sap from developing seeds in open bolls and stain the lint black. Seeds become discoloured and shrunken. Both nymphs and adults suck large amount of sap from leaves and stems depriving plants of essential nutrients showing the symptoms like retarded growth, late opening of bolls and total drying of the plant. They secrete honey dew on which black sooty mould develops, giving blackish appearance to the crop. Caterpillars feed on the cotton leaves and skeletonize them. In years of heavy infestation, the plants may be completely denuded of leaves.

Larvae roll the cotton leaves like a trumphet i.e. it rolls leaves in a funnel like shape and feeds by staying inside the funnel. In severe cases, defoliation occurs. Grub tunnels into the stem resulting into gall like swelling near the collar region of cotton stem. Young plants break at swelling older plants lose vigour. Grubs feed on the roots of cotton seedlings and destroy them. Adults feed on leaves, buds, flowers and young bolls by cutingt prominent round holes.

Management:  Use pheromone traps for monitoring of bollworms at a distance of 50 m @ 5 traps/ha and yellow sticky traps or yellow sheet with greese for monitoring & mass trapping of whitefly adults.  Trap cropping with castor against tobacco caterpillar, marigold against gram pod borer and okra against spotted bollworm.  Inter-cropping with mung bean, soybean, groundnut, ragi, maize, cowpea and onion reduces the infestation of boll worms. Intercropping with wild brinjal reduces the whitefly incidence.  Follow cultural practices like deep ploughing during April-May, removal and destruction of crop stubbles and roots, growing of early maturing & short duration varieties/hybrids, balanced use of fertilizers on soil test basis, frequent hoeings and weeding.  Growing of cotton at recommended spacing helps in reducing pest incidence because the dense crop harbours more of whitefly and Helicoverpa and wider spacing harbours more of leafhopper population.  Grazing cattle/goat/sheep in cotton fields after final picking reduces carry over of pests.  Removal of sticks at the base/root level avoids regeneration of the plants.  Stacking of sticks in the villages rather than in the fields reduces early infestation. 116

 Remove and destroy the pest infested plants/plant parts and weeds frequently so as to reduce the build up of the pests. Destroy pink boll worm larvae in rosette flowers and also through periodical removal of dropped squares, dried flowers and pre-matured bolls, to suppress pest population in the initial stage.  Pick up the advance staged larvae and destroy them in kerosinised or insecticide mixed water. In case of hairy caterpillar infestation make one foot wide and one foot deep trench along the field periphery and burry the migrating larvae therein it.  Complete ginning in January and destroy/burn the gin trash immediately.  Conservation and augmentation of predators like Coccinellids, Chrysoperla zastrowi Arabica, Syrphus sp, Scymnus sp. which predate upon different stages of leafhopper, whitefly, aphids, thrips and eggs of bollworms and parasitoids like Bracon brevicornis, Chelonus blackburni, Apanteles spp. against Spotted boll worm and Aenasius bamawalei against mealy bug. Trichograma spp. is effective egg parasitoids of bollworm pests.  Spray SLNPV against tobacco caterpillar and HaNPV against gram pod borer @ 250 LE/ha. Use Bt @ 1.5 kg/ha and neem based formulations.  Border crop with jowar, maize in 2 or 3 rows not only serves as a barrier for migration of insect pests but their pollen helps in attraction of beneficial Chrysoperla to the field. Chemical control of different Insect Pests of cotton: 1. Termites: In termite prone areas water soaked seed treated with chlorpyriphos 20 EC @ 10 ml/kg seed before sowing. After treatment, the seed should be shade dried for 25-30 minutes. 2. Sucking Pests:(Cotton leafhopper, whitefly, thrips, aphid etc.) . Insecticide Dose/acre Oxydemeton methyl (Metasystox) 25 EC 300-400 ml Dimethoate (Rogor) 30 EC 250-350 ml Imidacloprid (Confidor) 200 SL 40-50 ml Thiamethoxam (Actara) 25 WG 40-50 g Quantity of water per acre will be 120-150 L 3. Leaf eating insects: Hairy caterpillars, semilooper, grasshoppers, tobacco caterpillar field crickets etc. Quinalphos (Ekalux) 25 EC 600 ml Carbaryl (Sevin) 50 WP 600 g Quantity of water per acre will be @ 150-200 L/acre. 4. Bollworm pests: Spotted bollworms, Pink bollworm, and American bollworm Quinalphos (Ekalux) 25 EC 600-800 ml Triazophos (Hostathion) 40 EC 500-600 ml Carbaryl (Sevin) 50 WP 600-800 g Profenophos (Curacron/Profex) 50 EC 800 ml Neem (Nimbecidine/Achook) 300 PPM 1000 ml 5. Tobacco catterpiller: Thiodicarb 75WP 250-300 g Novaluron 10 EC 200ml Note: i.

Profenophos is a good ovicidal hence should be used when heavy egg load is there on the plant/fruiting bodies. 117

ii.

Do not use synthetic pyrethroids alone or in combination with other insecticides in Helicoverpa and whitefly infested fields. iii. For the control of spotted and pink bollworms use conventional (a) and synthetic pyrethroids (b) groups of insecticides on alternate turns but synthetic pyrethroids should not be used for more than two turns during the crop season. iv. Same insecticide or insecticides of the same group should not be used continuously. INSECT-PESTS OF MAIZE S No. Insect-pest Borers Maize stem borer 1. Chilo partellus Pyralidae:Lepidoptera

2.

Pink stem borer Sesamia inferens Noctuidae: Lepidoptera

3.

Sorghum Shootfly Atherigona soccata Muscidae: Diptera

Nature of Damage  

Central shoot withers, leading to dead heart formation. Larvae mines the midrib, enter the stem and feeds on the internal tissues.  Bore holes visible on the stem near the nodes.  Young larva crawls and feeds on tender folded leaves causing typical ―shot hole‖ symptom.  Affected parts of stem may show internal tunneling by caterpillars It generally attacks the crop in the late stage when cob formation starts in the field. Newly hatched larvae remain in group behind the leaf sheath and begin chewing on the stem and epidermal layer of the sheath. Whorl feeding of larvae results in rows of oblong holes in unfolding leaves unlike round shot holes produced by Chilo partellus. Later they bore into central shoot resulting in the drying up of the growing point and formation of dead heart in young maize plant. The attack is maximum in seedling stage. The tiny maggots creep down under the leaf sheaths till they reach the base of the seedlings. After this they cut the growing point or central shoot which results in the formation of characteristic dead hearts. Larva feeds on silk and developing grains.

Cob Borer Helicoverpa armigera Noctuidae: Lepidoptera Sap Suckers Maize aphid Nymphs and adults suck sap from leaves and tender ear 5. Rhopalosiphum maidis heads leading to mottled appearance with yellow patches, Aphididae:Hemiptera failure of grains to develop in ear head and formation of sooty mould due to honeydew excretion on the plants. It transmits maize dwarf mosaic virus. Leaf hopper Adults and the nymphs suck cell sap from the under 6. Pyrilla perpusilla surface of the lower leaves. Leaves turn yellowish white Lophopidae: Hemiptera and wither away. Due to continuous desapping by large number of hoppers top leaves in the affected canes dry up and lateral buds germinate. The hoppers exude a sweet 4.

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7.

Maize Shoot Bug Peregrinus maidis Delphacidae: Hemiptera

8.

Ear head bug Calocoris angustatus

Foliage Feeders and other insects Cutworms 9. A. flammatra, A. ipsilon, Army Worms Mythimna separate Noctuidae: Lepidoptera Ash weevil 10. Myllocerus sp. Curculionidae: Coleoptera Web worm 11. Cryptoblabes gnidiella (Pyraustidae: Lepidoptera) Hairy caterpillar 12. Amsacta albistriga Arctiidae:Lepidoptera

13.

14.

15.

Chaffer beetle Chiloloba acuta Scarabaeidae : Coleoptera Termites Microtermes obesi Termitidae: Isoptera White grub Holotrichia consanguinea Melolonthidae: Coleoptera

sticky fluid known as honeydew, which promotes quick and luxuriant growth of the fungus, capanodium species and as a result the leaves are completely covered by the sooty mould. This affects photosynthesis. Bugs are found within leaf whorls or on the leaves. Both nymphs and adults suck sap from tender portions of plants causing yellowing of foliage, stunted growth and scorched appearance. The leaves wither from top downwards. Panicle formation is inhibited and the plants die if attack is severe. Honeydew secreted by the bug causes growth of sooty mould on leaves Nymphs and adult suck the juice from within the grains in the milky stage as a result grains shrink, turn black in colour and become chaffy.Orange and pale green nymphs and adults are seen on the ear head. Caterpillars feed on ear heads. They cut tender stems of young and growing plants. Larvae hide during day time in the soil and become active at dusk. In severe cases, entire leaf is eaten. The field looks as if grazed by cattle. Larva feeds on the secondary roots and adults on leaves.

Larva first feeds on the lemma of the flowers scraping the chlorophyll and later on the milky grains. Webbing of maize cobs and feeding on the flowers and the grains. Newly hatched larvae feed gregariously by scraping the green matter on the under surface of the young leaves leaving upper epidermal layer intact. Later feed voraciously on the leaves leaving the petiole and midribs and main stem of the plants. They march from field to field in gregarious manner and affected field appear as if grazed by cattle. Adults feed on maize pollen which adversely affects pollination in northern part of India. Termite damage starts soon after sowing and continues till the growing stage. The leaves of damaged plants droop down which later wither and dry. Such plants are easily uprooted. Grubs feed on live roots resulting into drying of plant. Complete one generation in a year.

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Management:  Deep summer ploughing followed by fallowing helps in exposing resting stage of pests.  Inter-cropping with legume reduces borer incidence. E.g. Maize-Soybean/MaizeCowpea/ Maize-Green gram  Use of well decomposed farm yard manure (FYM) reduces termite attack.  Balanced use of fertilizers and supplement of micronutrient.  Use certified seeds of recommended verities having built-in mechanisms for resistance.  Removal of dead hearts will help to reduce second generation infestation.  Manual collection and destruction of white grub and chaffer beetle during adult emergence period reduces the pest population.  Soil application of neem cake for control of nematode and chaffer beetle  Conservation of naturally occurring biocontrol agents such as Trichogramma chilonis, Cotesia flavipes, Carabids, Coccinellids, Chrysoperla, spiders and wasps, etc.  Release of Trichogramma chilonis @ 1,60,000 /ha. on 7 and 15 days old crop and subsequently if required.  Need based and judicious application of pesticides is an important components of IPM.  Granular application of Carbofuran 3% CG @33.3kg/ha in whorls of infested plants to control stem borer and shoot fly.  Spray of Carbaryl 85% WP @ 1764 g/l against borer at 15-18 days after germination  Spray Monocrotophos 36% SL @ 625 ml/ha or Dimethoate 30% EC @ 1155 ml/ha or Oxydemeton methyl 25% EC @ 1000 ml/ha or Phorate 10% CG @ 30 Kg/ha for the management of shoot fly INSECT-PESTS OF SUGARCANE, COTTON AND MAIZE 1. Pink bollworm undergoes diapause in following stage. a) Pupal b) Egg c) Larval d) Adult

b) c) d)

Internode borer Root borer Top shoot borer

5. Pre-pupal parasitoid used for control of top shoot borer a) Trichogramma chilonis b) Isotima javensis c) Pharoscynmus horni d) Sturmiopsis inference

2. Dead heart formation in 1-3 month old sugarcane crop, which can be easily pulled out is due to attack of a) Internode borer b) Root borer c) Early shoot borer d) Top shoot borer 3. Presence of bore holes in sugarcane with fresh excreta in the nodal region and reddening of affected tissues is due to attack of a) Early shoot borer b) Internode borer c) Root borer d) Top shoot borer 4. Bunchy top in sugarcane is caused by a) Early shoot borer

120

6. a) b) c) d)

Sugarcane top borer pupates in Leaf Leaf sheath Soil Shoot

7. by a) b) c) d) 8. a)

Early shoot borer of sugarcane can be managed The release of Trichogramma sp. Granulosis virus Earthing up All the above An introduced pest on sugarcane Pyrilla perpusilla

b) Melanaspis glomerata c) Cavelerius excavates d) Ceratovacuna lanigera 9. Sugarcane depresella attacks a) Roots b) Leaves c) Shoot d) Flowers

root

c) Soil d) Boll

borer

17. Which of the following is not correctly matched? a) Drooping shoots and flared squares in cotton - Spotted boll worm b) Rosette bloom in cotton - American bollworm c) Gall like swelling near the collar region of cotton - Stern weevil d) Marginal downward rolling, cupping and yellowing of cotton leaves - Leaf hopper

Emmalocera

10. Epiricania melanoleuca is an ectoparasite of a) Pyrilla perpusilla b) Melanaspis glomerata c) Chilo infuscatellus d) Saccharicocus sacchari

18. Larvae of pink bollworm overwinter in a) Seed b) Soil c) Stem d) None of these

11. Circular bore hole in the boll plugged by the head of a larva is characteristic symptom of a) Pink boll worm b) Spotted boll worm c) American boll worm d) Spiny boll worm

19. Silvery sheen on the lower surface of the leaf in early stages of cotton is caused by a) White fly b) Leaf hopper c) Aphid d) Thrips

12. Flared squares in cotton is caused by e) Spodoptera litura f) Helicoverpa armigera g) Pectinophora gossypiella h) Earias vitella

20. Presence of shot holes and dead heart in maize are caused by i) Chilo partellus j) Atherigona soccata k) Rhopalosiphum maidis l) Peregrinus maidis

13. The boll worm which covers the opening once it enters into the boll a. Spotted boll worm b. American boll worm c. Pink boll worm d. None of the above

21. Which one of the following larva feeds on silk and developing maize grains a) Stem borer b) Earworm c) Web worm d) Cutworm

14. In cotton, gall like swelling near the collar region is caused by a. Pink Boll worm b. Stem weevil c. Red cotton bug d. Whitefly

22. Red cotton bug infestation is associated with a) Cotton mosaic b) Cotton wilt c) Nematospora gossypii d) Reddening of cotton leaf

15. Marginal downward rolling, cupping, yellowing, browning, bronzing and drying of cotton leaves is due to a) Whitefly b) Boll worms c) Cotton leaf hopper d) Cotton aphid 16. a) b)

23. Rosette flower produced by the infestation of a. American boll worm b. Spotted boll worm c. Pink boll worm d. None of the above

Site of oviposition of red cotton bug is Stem Leaves

in

cotton

is

24. Scientific name of Spiny bollworm of cotton

121

is a) b) c) d)

a) b) c) d)

Helicoverpa armigera Earias insulana Pectinophora gossypiella Earias vitella

25. Cotton leaf curl virus is transmitted by

122

White fly Aphid Jassids thrips


MAJOR INSECT PESTS OF CEREALS AND MILLETS AND THEIR MANAGEMENT VK Kalra Senior Scientist (Retd) Department of Entomology, CCS HAU, Hisar RICE (Oryza sativa L.; Family : Gramineae) 1. Yellow-stem borer, Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae) It is a specific pest of rice and is common in all the Asian countries. The caterpillars are destructive and, when full-grown, they measure about 20 mm and are dirty white or greenish yellow, having brown head and pronotum. The adults have a wing expanse of 25-45 mm and are yellowish white with orange yellow front wings. The females have a prominent tuft of brownish yellow silken hair at the tip of their abdomen. The female moth has a centrally situated black spot on each of the forewing. Life-cycle. In North of India, this pest is active from April to October and hibernates from November to March as a full-grown larva in rice stubble. The pupation starts sometimes in March and the emergence of moths begins in April. The moths become active after dusk when they mate and lay about 120 -150 eggs on the underside of the leaves in 2-5 clusters of 60-100 eggs each. The eggs are covered with yellowish brown hair of the female tuft. They hatch in 6-7 days and the tiny black-headed caterpillars soon bore into the stem from the growing points downwards. The larva grows in 6 stages and is full-fed in 16-27 days. It then constructs an emergence hole which is always located above the water level and pupates inside the attacked plant. Within 9 -12 days, it emerges as a moth. The life cycle is completed in 31 -46 days. There are 3 broods in Bengal, 2 in Orissa, 4-5 in Punjab, Andhra Pradesh and Tamil Nadu. Damage. The larva feeds inside the stem causing drying of the central shoot or ‗deadheart‘ in young plant and drying of the panicle or ‗white ear‘ in older plant. Basmati varieties suffer heavy damage than coarse varieties. Management. i) Remove and destroy stubbles at the time of the first ploughing after harvesting to decrease the carry-over. ii) Ploughing and flooding the field is effective in killing the larvae. iii) Clipping of tips of seedlings before transplanting reduce the carryover of eggs to the field. iv) Inundative releases of Trichogramma japonicum Ashmead @ 50,000 ha -1 during egg laying period of rice stem borer. v) The fields showing more than 5 per cent deadhearts should be sprayed with 875 ml of triazophos 40 EC or 2 litres of quinalphos 20 AF or 1.4 litres of monocrotophos 36SL or 2.5 litres of chlorpyriphos 20EC in 250 litres of water per ha. Alternatively, apply 2.5 kg of cartap hydrochloride 4G or 18.75 kg of carbaryl + gamma HCH 4G (Sevidol 4G) or 7.5 kg of phorate 10G or 20 kg carbofuran 3G or quinalphos 5G or 15 kg of fipronil 0.3G or 10 kg of chlorpyriphos 10G per ha in the standing water in the field. Same chemical 123

should not be used repeatedly. 2. Pink borer, Sesamia inferens (Walker) (Lepidoptera : Noctuidae) In North India, the pink borer has been recorded on rice, sugarcane, maize, sorghum and wheat, but its damage is significant on rice and maize only. The damage is caused by the caterpiltars which are pinkish brown and have a smooth cylindrical body, measuring about 25 mm. The moths are straw-coloured and have a stout body. Life-cycle. The pest is active from March-April to November on rice and then migrates to the wheat crop. The moths are nocturnal and lay eggs on leaves or on the ground. The eggs hatch in 6-8 days and the young caterpillars bore into the epidermal layers of the leaf sheath. Later on, they bore into the stem as a result of which the growing shoot dries up producing dead-hearts. When the attacked plants die, the larvae move on to adjoining plants. They are full-fed in 3-4 weeks and pupate inside the stem or in between the stem and leaves. The pupal stage lasts about a week and the life -cycle is completed in 6-7 weeks. There are 4-5 generations of the pest in a year. Damage. Same as in case of yellow stem borer. Management. Same as in case of yellow stem borer. Rice leaf-folder, Cnaphalocrocis medinalis (Guenee) (Lepidoptera : Pyralidae) The rice leaf folder is distributed in Indonesia, Korea, Malaysia, the Philippines, Pakistan and India. The moths are golden or yellowish brown and measure 8 -10 mm in length and 16-20 mm in wing expanse. Its greenish caterpillars are very agile and they feed inside the fold made by fastening together the edges of a leaf. Life cycle. The moths lay oval, creamy white eggs singly or in pairs on the undersurface of leaves and leafsheaths. The eggs hatch in 3 -4 days. The pale yellowish brown larva becomes full grown in 15-25 days. Pupation takes place in loose silken webs in between the leaves or in the leafsheaths and adults emerged in 6-8 days. Damage. The young larvae feed on tender leaves without folding them. The older larvae fasten the longitudinal margins of leaf together and feed inside the fold by scraping the green matter. The scraped leaves become memb ranous, turn white and finally wither showing white streaks on the leaves. A single larva may damage a number of leaves as it migrates from one leaf to another. Management. (i) Remove grassy weeds from bunds & around paddy fields. (ii) Collection & destruction of adults through light traps. (iii) Trichogramma japonicum Ashmead is an effective natural egg parasitoids of this pest (12 -60 % incidence). (iv) Spray any of the following insecticides at economic threshold (10 per cent damaged leaves): 875 ml of triazophos 40EC or 2.5 litres of chlorpyriphos 20EC, 1.4 litres of monocrotophos 36SL, 625 ml of fenitrothion 50EC, 425 ml of fenthion 1000EC, 1.0 kg of carbaryl 50WP or 2 litres of quinalphos 20AF in 250 litres of water per ha. Rice gall midge, Orseolia oryzae (Wood-Mason) (Diptera : Cecidomyiidae) The paddy gall-fly or gall midge is found in most of the paddy growing areas in the southern and eastern parts of India. The pest is also present in Pakistan, South-east Asia and Africa. The maggots of this fly, as a result of their feeding; produce galls and kill the growing shoots. Life cycle. The tiny pink fly lays reddish elongated eggs about 0.5 mm in length, singly or in clusters, on the leaves or on stems. During August to November, they hatch in 1-3 days. The tiny maggots crawl down to the base of the shoot and enter a young bud where they feed for 10-13 days and then pupate. The pupa wriggles its way up with the help of abdominal spines and cuts a hole at the tip of the gall from which the fly emerges after 4-7 days. The life-cycle is 124

completed in 15-23 days and the adults live for 3-4 days and lay upto 250 eggs. There are 3-5 overlapping generations on the same crop and 5-8 in a year. Damage. The maggot of this fly enters the stem and reaches the apical point of the central shoot or the tiller, where it develops. Owing to its feeding, some physiological changes take place which hamper the normal growth of the plant. The central leaf of an attacked tiller becomes hollow and deformed, and there is a swelling or gall formation on the basal portion. Its growth is stopped and the central leaf ultimately turns into a hollow outgrowth, giving a shining silvery colour called ‗silver shoot‘. Management. (i) Careful timing of planting can avoid damage; once past the tillering stage, the plant is not suitable as a host. (ii) Destroy grasses around the field. (iii) For gall midge areas, seedling root dip in 0.02 per cent emulsion of Ch1orpyriphos for 12 hours before transplanting protects the crop for 25-30 days. (iv) Platygaster oryzae Cameron (Platygasteridae) is the most important parasitoid of gall midge maggots. (v) Apply insecticides at economic threshold of 1 gall per m 2 in endemic areas or 5 per cent affected tillers in non-endemic areas. Spray 20-45 days after transplanting 625 ml of chlorpyriphos 20EC or 500 ml of quinalphos 20EC or fenitrothion 50EC in 750 -1000 litres of water per ha. Alternatively, apply granules as mentioned for the control of yellow stem borer. 5. Brown planthopper. Nilaparvata lugens (Stal) (Hemiptera: Delphacidae) The brown planthopper is the most destructive pest of rice in South and South -east Asia, China, Japan and Korea. In India, it has become very serious on the high -yielding varieties of paddy in many States including Uttar Pradesh, Madhya Pradesh, West Bengal, Andhra Pradesh and Tamil Nadu. Both adults and nymphs feed on paddy, sugarcane and grasses by sucking the cell sap. The brownish adults with brown eyes are 3.5-4.5 mm in length. The nymphs are brownish-black in colour and have greyish-blue eyes. Life cycle. The females start laying eggs within 3-10 days of their emergence and they deposit eggs in masses, by lacerating the parenchymal tissue. The number of eggs per mass varies from 2 to 11 and a female lays, on an average, 124 egg-masses. The eggs are somewhat dark and cylindrical, having two distinct spots. The incubation period ranges between 4 to 8 days. The nymphs, on emergence, start feeding on young leaves and after moulting 5 times, they become adults in 2 -3 weeks. The total cycle is completed in 18-24 days. Damage. Both the nymphs and adults cause damage by sucking cell sap from the leaves which turn yellow and the entire plant may dry up. The population increases very rapidly and the rice fields start drying up in patches known as hopperburn. The loss in yield may range from 10 to 70 per cent. This insect is known to transmit the grassy stunt virus disease of rice. Management. (i) Avoid close spacing (15 x 10 cm) and prefer a spacing of 20 x 15 cm. (ii) Alternate drying and wetting the field during peak infestation, and draining out the standing water from the field 2-3 times. (iii) The releases of mirid bug, Cyrtorhinus lividipennis Reuter, @ 100 bugs or 50-75 eggs/m2 at 10-day intervals. The presence of 3 predatory spider, Lycosa pseudoannulata (Bosenberg & Strand), per hill has been found to check the population of the pest. (iv) Spray at economic threshold (5-10 insects per hill): 100 ml of Imidacloprid 200 SL, 625 g of carbaryl 50 WP or 625 ml of fenthion 1000 EC or 2.0 litres of quinalphos 25 EC or 2.5 125

litres of chlorpyriphos 20 EC or 1.4 litres of endosulfan 35 EC or 1.4 litres of monocrotophos 36 SL in 250 litres of water per ha. Repeat application if hopper population persists beyond a week after application. While spraying nozzle should be directed at the basal portion of the plants. 6. Whitebacked planthopper, Sogatella furcifera (Horvath) (Hemiptera : Delphacidae) The whitebacked planthopper has assumed the status of a serious pest of rice in many Asian countries particularly India, Myanmar, Cambodia, Sri Lanka, China, Pakistan, Vietnam and Philippines. It is widespread in many parts of India. The adult is a straw-coloured, wedge-shaped insect, with white back he nymph is greyish-white and turns dark grey when it nears maturity. Life-cycle. The planthoppers breed continually in southern parts of India where paddy crop is available throughout the year. In northern parts, the planthopper becomes active in May in the paddy nursery, from where it shifts to the transplanted crop. The adults lay eggs generally on the leaf sheath. The eggs hatch in 3.4 -4.6 days. The nymphs feed on leaves and are transformed into adults within 8.9 -13.1 days. The life-cycle is completed in 12.3-17.7 days. The adult females live for about a week. There are several generations in a year. Damage. The nymphs and the adults suck cell-sap from the leaf surface and tend to congregate on the leaf-sheath at the base of the plant. The leaves of attacked plants turn yellow and later on rust red. These symptoms start from the leaf tips and spread to the rest of the plant. The attacked plants ultimately dry up without producing ears. The insect also excretes honeydew on which a sooty mould appears, imparting a smoky hue to the paddy fields. Management. Same as in case of brown planthopper. The economic threshold is 10 insects per hill. 7. Green leafhoppers, Nephotettix nigropictus (Stal) and N.virescens (Distant) (Hemiptera: Cicadellidae) The green leafhoppers are found in all the rice growing regions of India, although they assume pest proportions only during certain years in Madhya Pradesh, Andhra Pradesh, Orissa and West Bengal. These species are also known pests of rice in Japan, the Philippines, Formosa and Sri Lanka. Life cycle. The females, after undergoing a pre-oviposition period of 6-9 days, lay eggs on the inner surface of the leaf-sheath in groups of 3-18. The eggs hatch in 3-5 days and the nymphal stage is completed in 12-21 days. The adults live for 7-22 days in summer. There are about six overlapping generations from March to November. The insect over winters in the adult stage. Damage. The nymphs and the adult suck sap from the leaves, turning them yellow and ultimately brown. The plants lose vigour. N. virescens is also known to be the vector of tungro virus. Management. Same as in case of brown planthopper. 8. Rice hispa, Dicladispa armigera (Olivier) (Coleoptera:Chrysomelidae) Rice hispa is distributed throughout India but often serious on young rice crop in parts of Andhra Pradesh, Tamil Nadu, West Bengal, Punjab and Himachal Pradesh. The adult is a small bluish black beetle (5 mm in length) and is recognized by numerous short spines on the body. The legless, creamy-white larvae are not easily seen, because they are concealed inside the leaf tissue. Life-cycle. The eggs are embedded in the leaf tissue towards the tip. On hatching, the 126

young grubs feed as leaf-miners, between the upper and lower epidermis. The attacked leaves turn membranous, showing characteristic blisters or blotches. Later on, the attacked leaves wither and die. When the larvae are full -grown, they pupate inside and finally emerge as black beetles. The insect completes about six generations in a year. Damage. Apart from the damage caused by larvae as leaf-miners, the adults also feed on green matter and produce parallel whitish streaks on the leaves. The damage starts in nurseries and spreads to the rice fields. Management. (i) Clip off & destroy the infested leaf tips, while transplanting. (ii) If the nursery beds are flooded, the beetles float and can be swept together with brooms and then destroyed. (iii) Spray at economic threshold (1 adult or 1-2 damaged leaves per hill) with 300 ml of methyl parathion 25EC or 625 ml of fenitrothion 50EC or chlorpyriphos 20EC or 2.5 litres of lindane 20EC in 250 litres of water per ha. If the attack continues, repeat spray after two weeks. 9. Paddy root weevil, Echinocnemus oryzae (Marshall) (Coleoptera : Curculionidae) The paddy root weevil is a serious pest of rice in southern India. In recent years, it has spread to some other states like Punjab, Orissa and U.P. Damage is caused by the grubs which feed on rootlets of paddy plants. They are translucent white and measure about 6 mm in length. There are si x pairs of prominent tubercles on the dorsal side of the abdomen. Life-cycle. The weevils emerge in July with the first shower of rain and are seen sitting in large numbers on rice plants at this time. The eggs which are laid on the plant hatch in a few days. The grubs lead an aquatic life and feed on the root -hairs. Grubs are fullgrown by the middle of September when they bury themselves deep into the soil for pupation. The pupae emerge next year in July and, thus, the pest completes only one generation in a year. Damage. The grubs feed on root hairs of the transplanted crop, thereby affecting plant growth. The infested crop remains stunted and a large number of plants are killed. The crop transplanted in July is more. Management. Apply 7.5 kg of phorate 10G or 25 kg of carbofuran 3G or 12.5 kg of diazinon 5G or 20 kg of lindane 6G per ha in standing water. 10. Rice bug, Leptocorisa acuta (Thunberg) (Hemiptera : Coreidae) The rice bug, commonly known as gundhy bug, is widely distributed in India, the Orient and Australia. It is a serious pest of rice in several parts of India. Apart from rice, it also feeds on maize, millets, sugarcane and some grasses. The adults are slender, about 20 mm long and greenish brown. They have long legs and antennae with four joints. The newly hatched nymph is about 2 mm long and is pale green. However, as it grows, the green colour deepens. Life-cycle. The females lay 24-30 round yellow eggs in rows on the leaves. The eggs hatch in about 6 or 7 days and the nymphs grow to maturity in six stages within 2 or 3 weeks. The adult bugs live for 33-35 days. Many generations are completed in a year. Damage. Rice fields severely attacked by this pest emit a repugnant smell which gives to this pest the name 'gundhy' bug. The nymphs and the adults suck juice from the developing grains in the milky stage, causing incompletely filled panicles or panicles with empty grains. Black or brown spots appear around the holes made by the bugs on which a sooty mould may develop. Management. i) The population can be suppressed by killing the bugs by using light traps, 127

collecting the adults with nets and destroying the weeds to remove alternative hosts. ii) Dust carbaryl 5 per cent or malathion 5 per cent @ 25 kg per ha. Others Pests of Rice Other pests recorded in various parts of India and adjoining countries are the grasshoppers, Hieroglyphus banian (Fabricius) and Oxya nitidula Walker; (Orthoptera : Acrididae); Zig-zag leafhopper, Recilia dorsalis (Motschulsky), white rice leafhopper, Cofana spectra (Distant) and rice blue leafhopper, Typhlocyba maculifrons (Motschulsky) (Hemiptera : Cicadellidae); the rice root aphid, Rhopalosiphum rufiabdominalis (Sasaki) and wheat aphid, Schizaphis graminum (Rondani) (Hemiptera : Aphididae); rice mealy bug, Ripersia oryzae Creen (Hemiptera : Coccidae); the rice thrips, Stenchaetothrips biformis (Bagnall) and Haplothrips ganglbauri Schmutz (Thysanoptera : Thripidae); the rice skipper, Pelopidas mathias (Fabricius) (Lepidoptera : Hesperiidae); the rice horned caterpillar, Melanitis ismene (Cramer) (Lepidoptera: Nymphalidae); the yellow hairy caterpillar, Psalis pennatula (Fabricius) (Lepidoptera : Lymantriidae); paddy swarming caterpillar, Spodoptera mauritia (Boisduval) and rice ear-cutting caterpillar, Mythimna separata (Walker) (Lepidoptera : Noctuidae); rice caseworm, Parapoynx stagnalis Zeller, pale headed striped borer, Chilo suppressalis (Walker); dark-headed striped borer, Chilo polychrysus (Meyrick); white stem borer, Scirpophaga innotata (Walker); Chilo indicus (Kapur) and Chilo infuscatellus, Snellen (Lepidoptera: Pyralidae) the whorl maggot, Hydrellia philippina Ferino (Diptera : Ephydridae); the root weevils, Tanymecus indicus Faust and Hydronomidius molitar Faust (Coleoptera : Curculionidae). MAIZE (Zea mays L.; Family : Gramineae) Maize borer, Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) It is the most destructive pest of maize and sorghum in Sri Lanka, India, Pakistan, Afghanistan, Uganda, Central and East Africa. It is found throughout India . This insect has also been recorded on bajra (Pennisetum typhoides), sugarcane, Sudan grass, baru (Sorghum halepense), sarkanda (Saccharum munja) and some other grasses. The grown up caterpillars are about 20-25 mm long and dirty greyish white, with black head and four brownish longitudinal stripes on the back. The adults are yellowish grey moths, about 25 mm across the wings. Life-cycle. The eggs are laid in clusters of 50-100 in rows on the undersurface of the leaves during April-May. A female lays over 300 eggs during its life-span of 2-12 days and the eggs hatch in 4-5 days in summer. The young larvae first feed on the leaves, making a few shot holes and then bore their way downwards through the central whorl as it opens. The larva becomes full-fed in 14-28 days, passing through six stages and after making a hole in the stem pupates inside it. The life -cycle is completed in about 3 weeks and there are probably 5 generations in a year. The full -grown caterpillars of the last generation hibernate in stubble, stalks, etc., and remain there till the next spring. Damage. The damage is done by the caterpillars by feeding inside the stem and producing ‗deadhearts‘. About 25-50 per cent of the plants are destroyed. Management. (i) Destroy the stubbles, weeds and other alternate hosts of the stem borer by ploughing the field after harvest. (ii) Remove and destroy dead -hearts and destruction of infested plants showing early pin-hole. (iii) Destruction of crop residues and chopping of stems harbouring diapausing larvae could be very effective in reducing borer population. (iv) Release Trichogramma spp. at the first sight of egg masses of maize borer and synchronize the release of Apanteles sp. or Microbracon sp. adults with the larval development. (v) (a) Spray the crop 2-3 weeks after sowing or as soon as 128

borer injury to the leaves is noticed with any of the following synthetic pyrethroids using 125 litres of water per ha: fenvalerate 20EC @ 100 ml/ha, cypermethrin 10EC @ 100 ml/ha or deltamethrin 2.8EC @ 200 ml/ha. (b) Alternatively, the crop should be sprayed with any of the following insecticides: endosulfan 35EC @ 250 ml/ha, monocrotophos 36SL @ 275 ml/ha, lindane 20EC @500 ml/ha, fenitrothion 50EC @ 440 ml/ha or carbaryl 50WP @ 250 g/ha. (c) After this spray, apply twice at 7-10 days intervals any of the following insecticides in the whorls of only infested plants that show fresh borer injury in the central leaves: fenitrothion or trichlorphon 5 per cent dust or endosulfan 4G, lindane 6G, carbaryl 4G or trichlorphon 4G. In case of dust, mix it with equal quantity of moist soil before application. Apply a pinch of this mixture to the whorl of plants. Usually 1.5-2.5 kg of the insecticide would be required per ha for one application. Apply granules to the whorl of plants @ 0.5 -1.25 kg/ha per application through a bottle with a few holes in its cap. Other Pests of Maize The maize crop is also attacked by Deccan wingless grasshopper,Colemania sphenarioides Boliver (Orthoptera : Acrididae); the aphids, Rhopalosiphum maidis (Fitch) and rusty plum aphid, Hysteroneura setariae (Thomas) (Hemiptera: Aphididae); maize jassid, Zygnidia manaliensis Singh (Hemiptera: Cicadellidae); sugarcane leafhopper, Pyrilla perpusilla (Walker) (Hemiptera: Lophopidae); thrips, Anaphothrips sudanensis Trybon, Caliothrips graminicola (B&C) and Haplothrips gowdeyi (Franklin) (Thysanoptera : Phlaeothripidae); termites, Odontotermes obesus (Rambur) and Microtermes anandi Holmgren (Isoptera : Termitidae); the pink borer, Sesamia inferens (Walker); the gram borer, Helicoverpa armigera (Hubner), swarming caterpillar, Spodoptera exempta (Walker) and armyworm, Mythimna separata (Walker) (Lepidoptera : Noctuidae); red hairy caterpillar, Amsacta moorei (Butler) (Lepidoptera : Arctiidae); cob-borer, Anatrachyntis simplex Wlsm. (Lepidoptera : Cosmopterygidae); leaf weevil, Myllocerus discolor Bohemann (Coleoptera : Curculionidae); blister beetle, Mylabris macilenta Mshll., (Coleoptera : Meloidae); white grubs, Holotrichia consanguinea Blanchard, (Coleoptera : Melolonthidae) and stem fly, Atherigona soccata Rondani and A. naquii Steyskal (Diptera : Muscidae). SORGHUM, Sorghum bicolor (L.) Moench.; Family: Gramineae) 1. Sorghum shoot fly, Atherigona soccata Rondani (Diptera : Muscidae) The sorghum shootfly, also known as the sorghum stemfly, is a widely distributed pest in Europe, Africa and Asia. In India, it is more serious in southern parts. Besides sorghum, it infests maize, wheat, broom corn, small millets (Panicum spp.) and grasses. Life-cycle. The female fly lays approximately 40 eggs singly on the underside of the leaves during its life span of about one month. The eggs hatch in 1-2 days and the tiny maggots creep out and reach in between the sheath and the axis, and bore into the stem. They feed inside the main shoot for 6-10 days and, when full grown, they may pupate either inside the stem or come out and pupate in the soil. The pupal period in the summer lasts about a week. Several generations are completed in a year. In northern India, the pest over-winters in the pupal stage. Damage. The insect attacks the young crop when it is in the six -leaf stage. As the maggots feed on the main shoot, the growing point is destroyed and by the time they pupate, the plant is almost dead. The young plants show typical dead-heart symptoms. When the attacked plants are somewhat older, tillers are produced, which mature later 129

than the main crop. The total loss in yield is sometimes as high as 60 per cent. Management. (i) Seed coating with isofenphos 5G @ 30 g per 100 g seed provides protection against shootfly upto 2 weeks. (ii) In case seed treatment has not been done, apply carbofuran 3G, phorate 10G, chlorpyriphos 5G or disulfoton 5G in furrows before sowing @ 3 g per metre row. 2. Sorghum earhead bug Calocoris angustatus Lethiery (Hemiptera: Miridae) It is one of the most destructive pests of sorghum in southern India. The adult is a small, slender, greenish yellow bug, measuring 5-8 mm in length and over 1 mm in width. This bug has been recorded feeding on a number of cereals, millets and grasses, but its breeding is mainly restricted to sorghum, on which it assumes the status of a pest. Life-cycle. The adults appear on sorghum crop as soon as the ears emerge from the leaf sheaths. The bug lays eggs under the glumes or in between anthers of florets, by inserting its ovipositor. The female lays 150-200 eggs which are cigar- shaped and measure about 1.5 mm. The eggs hatch in 5-7 days and the nymphs start feeding on developing grains in the milk stage. The nymphs pass through 5 instars and develop into adults in about 3 weeks. The adults of the second generation are again ready to oviposit in the ears having developing grains which might be available on the same crop. As soon as the grains are ripe, the bugs stop multiplying on that crop. The insect completes its life -cycle in about one month and produces a number of generations in a year. Damage. Both the nymphs and the adults feed on the green earheads. As a result of feeding by the bugs, the grains remain chaffy or shrivelled. When a large army of tiny nymphs feeds, the whole ear may become blackened at first and may eventually dry up, producing no grains. Management. Spray 625 ml of malathion 50EC or one litre of endosulfan 35EC or 3 kg of carbaryl 50 WP or 200 ml of phosphamidon 85 WSC in 500 litres of water per ha. Other Pests of Sorghum Some other insects which damage jowar include the sorghum midge, Contarinia sorghicola (Coquillett) (Diptera : Cecidomyidae). Deccan wingless grasshopper, Colemania sphenarioides Bol. and Hieroglyphus nigrorepletus Bolivar (Orthoptera : Acrididae); the aphid, Rhopalosiphum maidis (Fitch), (Hemiptera : Aphididae); mealy bug, Heterococcus rehi (Lindinger) (Hemiptera: Pseudococcidae); whitefly, Neomaskelliia bergii (Signoret) (Hemiptera : Aleyrodidae); rice gundhy bug, Leptocorisa acuta (Thunberg) (Hemiptera : Coreidae); leafhopper, Pyrilla perpusilla (Walker) (Hemiptera : Lophopidae); the shoot bug, Peregrinus raidis (Ashmead) (Hemiptera : Delphacidae); the thrips, Anaphothrips sudanensis (Trybom), (Thysanoptera : Thripidae); the pink stem borer, Sesamia inferens (Walker); gram pod borer, Helicoverpa armigera (Hubner); the semilooper, Antoba silicula Swinhoe; armyworm, Mythimna separata (Walker) (Lepidoptera : Noctuidae); stem borer, Chilo partellus (Swinhoe) (Lepidoptera : Pyralidae); the leaf-roller, Marasmia trapezalis (Guenee); the web worm, Cryptoblabes gnidiella (Millere) (Lepidoptera : Pyralidae) hairy caterpillars, Amsacta albistriga (Walker) and A. moorei (Butler) (Lepidoptera : Arctiidae) and the white grubs, Holotricha consanguinea Blanchard (Coleoptera : Scarabaeidae).

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WHEAT (Triticum spp.; Family: Gramineae) 1. Wheat aphid, Macrosiphum miscanthi (Takahashi) (Hemiptera : Aphididae) Wheat aphid is widely distributed in India. The insects are green, inert, louse like and appear on young leaves or ears in large numbers during the cold and cloudy weather. Life-cycle. The wheat aphid breeds at fast rate during the cold weather and reaches the height of its population in February-March when the ears are ripening. The females give birth to young ones and are capable of reproducing without mating. During the active breeding season, there are no males and the rate of reproduction is very high. When the wheat crop is ripe and the summer is approaching, the winged forms of both males and females are produced and they migrate to other plants like doob grass (Cynodon dactylon). In October- November, the aphids again appear on wheat. Damage. These plant lice suck sap from the ears and t ender leaves, and decrease yield of the crop. The damage is particularly severe in years of cold and cloudy weather. The losses due to aphids have been reported upto 36 per cent. Management. Spray 375 ml of dimethoate 30EC or oxydemeton methyl 25EC or monocrotophos 36SL or formothion 25EC in 425 litres of water per ha. Armyworm, Mythimna separata (Walker) (Lepidoptera Noctuidae) The armyworm is a pest of graminaceous crops all over the world. In India, it is a sporadic pest of wheat, sugarcane, maize, jowar, bajra and other graminaceous crops. Life-cycle. The adult moths of armyworm are pale brown. They live for 1 -9 days and lay eggs singly in rows or in clusters on dry or fresh plants or on the soil. They hatch in 4-11 days from March to May, and in 19 days in December- January. Freshly emerged larvae are very active, dull white and later turn green. In the spring, the larval stage is completed in 13-14 days, but in the winter it is prolonged to 88-100 days. In the pre-pupal stage, the insect spins a cocoon. The pre-pupal stage lasts 1-11 days during January to May. Pupation usually takes place in the soil at a depth of 0.5-5 cm, but it may also occur under dry leaves among the stubble or fresh tillers. The pupal stage is completed in 9-13 days in May and 36-48 days in the winter months. The survival of the pupae depends on the soil moisture. Damage. The freshly emerged larvae spin threads from which they suspend themselves in the air and then with the help of air currents reach from one plant to another. In the early stages, they feed on tender leaves in the central whorl of the plant. As they grow, they are able to feed on older leaves also and skeletonize them totally. In the case of a severe attack by the armyworms, whole leaves, including the mid-rib, are consumed and the field looks as if grazed by cattle. Management. (i) Collect and destroy the caterpillars. (ii) Spray 875 ml of fenitrothion 50EC or 500 ml of dichlorvos 80SL or 3 kg of carbaryl 50WP or 1.25 litres of trichlorphos 50EC or one litre of quinalphos 25EC in 425 litres of water per ha. 3. Ghujhia weevil, Tanymecus Indicus Faust (Coleoptera: Curculionidae) Glujhia weevil is widely distributed in the Indian Sub-continent and is a sporadic pest of considerable importance, feeding on germinating rabi crops, particularly wheat, barley, gram and mustard.Weevils are earthen grey and measure about 6.8 mm in length and 2.4 mm in width. Their fore wings arc oblong and hind wings are more or less triangular, but they cannot fly. Life cycle. The weevils lay 6-76 eggs in 5-11 instalments in the soil under clods or in crevices in the ground. The eggs hatch in 6-7 weeks and the young grubs enter the soil 131

where they feed, probably on soil humus. They are full grown in 10 -18 days and pupate in earthen chambers at a depth of 15-60 cm. The pupal stage lasts 7-9 weeks, and the adults emerge next year in June or July. The pest has only one generation in a year. Damage. The adults feed on leaves and tender shoots of the host plants. The damage is particularly serious during October-November, when the rabi crops are germinating. Weevils cut the seedlings at the ground level and often the crop has to be resown. Management. Dust carbaryl or malathion 5 per cent @ 25 kg per ha. Other Pests of Wheat The other pests of wheat are the termites, Odontotermes obesus (Rambur) and Microtermes obesi Holmgren (Isoptera : Termitidae ); the aphids, Schizaphis graminum (Rondani) and Rhopalosiphum maidis (Fitch) (Hemiptera: Aphididac); Laodelphax striatella (Fallen) (Hemiptera: Delphacidae); the sugarcane leafhopper, Pyrilla perpusilla (Walker) (Hemiptera: Lophopidae); the wheat bug, Eurygaster maura (Linnaeus) (Hemiptera: Pentatomidae); the wheat thrips, Anaphothrips favicinctus Karny (Thysanoptera : Thripidae); the cut worms, Agrotis spp. (Lepidoptera: Noctuidae); Marasmia trapezalis (Guenee) (Lepidoptera: Pyraustidae); the pink borer, Sesamia inferens (Walker) (Lepidoptera: Noctuidae); the shootfly, Atherigona naqvii Steyskal and A. orzae Malloch (Diptera : Muscidae); and flea beetle, Chaetocnema basalis Baby (Coleoptera: Chrysomelidae). Multiple choice questions* : 1. Scientific name of yellow rice stem borer is : a. Scirpophaga incertulus, b. Bagrada sp. c. Lipaphis erysimi d. Sesamia inferens 2. Rice yellow stem borer, Scirpophaga incertulus belongs to family: a. Pyralidae b. Noctuidae c. Gelechidae d. None of these 3. Dead heart & white ear symptoms appear due to the incidence of: a. Yellow stem borer b. Rice bug c. Ghujia weevil d. All of these. 4. Scientific name of pink borer is : a. Sesamia inferens b. S. nivella c. Cnaphalocrocis medinalis d. None of these 5. Damage symptoms of rice leaf folder are : a. White streaks on leaves b. Dead heart formation c. Shot holes on leaves d. None of these 6. Scientific name of rice leaf folder is : a. Cnaphalocrocis medinalis b. Scirpophaga incertulus c. Sesamia inferens

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d.

None of these

7. a. b. c. d.

Scientifically rice gall midge is called: Orseolia oryzae Sesamia inferens Tetrasticus sp. Scirpophaga incertulus

8. is : a. b. c. d.

Scientific name of brown plant hopper of rice

9. a. b. c. d. 10. in : a. b. c. d.

Nilaparvata lugens belongs to family : Delphacidae Cicadellidae Aphididae Noctuidae Incidence of plant hoppers on rice crop results

11. called : a. b. c.

White backed plant hopper is scientifically

Nilaparvata lugens, Amrasca biguttula Heiroglyphus banian None of these

Hopper burn symptoms Leaf curling Shot holes on leaves White streaks on leaves

Sogatella furcifera Nilaparvata lugens, Amrasca biguttula

d.

Heiroglyphus banian

b. Bactrocera dorsalis c. Musca domestica d. None of these 22. Typical symptoms of damage caused by Atherigona soccata is : a. Dead heart formation of seedlings b. Dead heart formation of grown up plants c. Lodging of plants d. None of these 23. Scientific name of sorghum earhead bug is : a. Calocoris angustatus b. Peregrines maidis c. Leptocorisa acuta d. None of these 24. Scientific name of wheat aphid is : a. Macrosiphum miscanthi b. Aphis craccivora c. Aphis fabae d. Lipaphis erysimi 25. How do aphids cause damaged to plants ? a. Suck sap b. Bite holes in leaves c. Bore in stem d. None of these 26. Scientific name of army worm is : a. Mythimna separata b. Scirpophaga inferens c. Helicoverpa armigera d. None of these 27. Scientific name of ghujia weevil is : a. Tanymecus indicus b. Sitophilus oryzae c. Echinocnemus sp. d. None of these 28. Scipophaga incertulus lays eggs on : a. Underside of leaves b. On leaf sheaths c. On panicles d. None of these 29. Brown plant hopper lays eggs by / on: a. Lacerating the parenchymal tissue b. Piercing the panicles c. Leaf sheath d. None of these 30. Rice bug, Leptocorisa acuta belongs to family: a. Coreidae b. Pentatomidae c. Cicadellidae d. lygaeidae *option/choice ―a‖ of each question is the correct answer.

12. Green leaf hopper, Nephotettix sp. belongs to family : a. Cicadellidae b. Delfacidae c. Gelechidae d. Aphididae 13. Numerous short spines are present on the body of which of the following insects? a. Rice hispa b. Ghujia weevil c. Root weevil d. Lady bird beetle 14. Rice hispa belongs to family: a. Chrysomelidae b. Coccinilidae c. Curculionidae d. None of these 15. Weevils belong to family: a. Curculionidae b. Chrysomelidae c. Coccinillidae d. None of these 16. Rice fields attacked severely by Leptocorisa acuta : a. Emit a repugnant smell b. Dry away c. Lodge down d. Mature early 17. Scientific name of maize borer is: a. Chilo partellus b. Sesamia inferenes c. Earias sp. d. None of these 18. Chilo partellus belongs to family: a. Pyralidae b. Noctuidae c. Gelechidae d. None of these 19. Damage caused by Chilo partellus results in : a. Dead heart formation b. White ears c. Shedding of pollens d. None of these 20. Sorghum shoot fly belongs to family: a. Muscidae b. Tephritidae c. Cerambecidae d. None of these 21. Scientific name of sorghum shoot fly is: a. Atherigona soccata

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MAJOR INSECT PESTS OF PULSES AND THEIR MANAGEMENT Roshan Lal Department of Entomology CCS HAU Hisar Introduction India is a major pulses growing country in the world, sharing 35-36 and 27-28% of the area and production of these crops, respectively. It is producing 12-14 million tonnes of pulses from 22-24 million hectares of land. The commonly grown pulses crops in India are chickpea (Cicerarietinum), pigeonpea (Cajanus cajan), mungbean (Vigna radiata), urdbean (Vigna mungo), horsegram (Macrotylomabiflorus), mothbean (Vigna acontifolia),lathyrus (Lathyrussativus), lentil (Lens culinaris), cowpea (Vigna unguiculata), drybean (Phaseolus vulgaris) and peas (Pisumsarivum). A few minor pulses such as ricebean (Vigna umbellata) and fababean (Viciafaba) are grown in specific areas only. Pulses are rich source of protein to vegetarians and have inherent capacity to fix large amount of atmospheric nitrogen in symbiotic association with Rhizobium. Among various limiting factors for low yield of pulses crops, the incidence of insect pests assumes great significance. A number of insect pests are associated with pulse crops. Of these, gram pod borer, Helicoverpa armigera (Hub.), pod bug (Clavigralla gibbosa), pod fly (Melanagromyza obtusaMalloch), blister beetle (Mylabris spp.), hairy caterpillars (Amsactamoorei (Butler) andSpilosomaobliqua Walker), cutworms (Agrotisypsilon (Huf.) and AgrotisflammatraSchiffer –Muller), semilooper (Autographanigrisigna (Walker) and Thysanoplusiaorichalcea, bean black aphid (Aphiscraccivora Koch.)termites (Odontotermesobesus (Rambur) and Microtermesobesi Holm)and whitefly (Bemisiatabaci (Genn.) are of economic importance. However, Dharamsena (1990) described Opiomyiaphaseoli, H. armigera, Marucavitrata, Lampidesboeticusand Etiellazinckenella are the most important in fields while the Callosobruchus spp. in the storage conditions. Gram pod borer, Helicoverpaarmigera (Hub.)Noctuidae: Lepidoptera Gram pod borer, Helicoverpaarmigera is the single most important pest of legumes, cotton, cereals, vegetables, okra, tomato, Berseemand pulses crops in Asia, Africa, Australia and the Mediterranean Europe. Adult: The moth is stout built and light brown in colour with 35-40 mm wing span and 12-20 mm long. Forewings are grey to brown with network of fine, wavy, dark lines, brown band near the edges of forewings, hind wings buff with a dark band near the edge, which contains a pale section underside of wings, forewings has a dark comma like mark underside. Flights occur at dust and night time.

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Larva: Body colour of the larvae varies from green, yellow, pink and reddish brown to almost black with a broad cream stripe running over spiracles along each side. Larva passes through six instars and full grown larva is up to 40 mm long. Larvae feed on over 120 plant species of cultivated and wild plants. The elder larvae when come in contact cannibalize with each other. Egg: The spherical egg is 0.5 mm in diameter, white to brown in colour and have costate surface. The incubation period is three days. Female moth lays several hundred (740) eggs singly or small clusters on various parts of their host plant. They hatch in 2-4 days in April to October and 6 days in February and the young larvae feed on the foliage for some time and later bore into the pods and feed on developing grains, with body hanging out side. They move from pod to pod and are full fed in 13-19 days.

Pupa: The pupa is pale to dark brown in colour and 15-20 mm in length. The pupae develop inside a silken cocoon in the soil at a depth of 4-10 cm. Pupal period varies from 8-15 days. The total life cycle is completed 4-6 weeks. Management: 1. Grow early maturing, short duration and tolerant varieties. 2. Removal of crop stubbles and destroy the weed as they provide food and shelter to the pest. 3. Use pheromone and light traps to monitor and collect male moth population. 4. Mixed intercropping with non preferred host plants like barley, wheat, mustard and linseed should be preferred over sole crops. 5. Hand picking of the older larvae during early hours of the day is helpful as these are less susceptible to insecticides. 6. Apply Nuclear Polyhedrosis Virus @ 250-500 LE/hain 500-750 l water alone or in combination with insecticides. 7. Release Trichogrammachilonis and larval parasitoid, CampoletischloridaeUshida to manage the pest in field conditions. 8. Neem based insecticide like nimbecidine is also effective which acts as antioviposition and antifeedant against this pest. Chickpea: Azadirachtin 0.03% Neem oil based @ 2500-5000 ml in 500 to 1000 lit of water/ha. Bacillusthruringiensisvar, kurstaki serotype H- 3a, 3b strain Z-52 @ 0.75kg in 500-750 lit water/ha. Beauveriabassiana 1% WP @ 3kg in 500 lit water/ha. Chlorantraniliprole 18.5 SC @ 125 ml in 500 litwater/ha. Lambda-Cyhalothrin 5EC @ 500 ml in 300-400 l water.Monocrotophos 36SL @ 1250 ml in 500-1000 l water.Novaluron 10EC @ 750 ml in 500 l water.Quinalphos 25EC @ 1000 ml in 500-1000 l water. For the management of cut worm, spray chlorpyriphos 20EC @ 2.5 l in 500-1000 l water/ha.Quinalphos 1.5% DP @ 23.3 kg/ha. 135

Pigeonpea: Azadirachtin 0.03% Neem oil based @ 2500-5000 ml in 500 to 1000 lit of water/ha. Bacillusthruringiensisvar, kurstaki serotype H- 3a, 3b strain Z-52 @ 0.75 kg in 500-750 lit Water/ha. Chlorantraniliprole 18.5 SC @ 150 ml in 500-750 lit water/ha.Lambda-Cyhalothrin 5EC @ 400-500 ml in 400-600 l water.Monocrotophos 36SL @ 1250 ml in 500-1000 l water.Quinalphos 25EC @ 1400 ml in 500-1000 l water.Spinosad 45SC @ 125-162 ml in 8001000 l water.Benfuracarb 40EC @ 2500 ml in 500 lit water.Lufenuron 5.4EC @ 600 ml in 5001000 l water/ha.Methomyl 40SP @ 750-1125 ml in 500-1000 water/ha. Spray HaNPV 250-500 LE/ha in 500-750 l water.Quinalphos 20AF @ 205 l in 750-1000 l water/ha.Quinalphos 1.5% DP @ 23.3 kg/ha. Greengram: Monocrotophos 36SL@ 437 ml in 500-1000 l water or Phenthoate 50EC @ 2000 ml in 500-1000 l of water.Methyl parathion 2D @ 25 kg/ha. Blackgram: Chlorantraniprole 18.5SC @ 100 ml in 500 lit of water or Lufenuron 5.4EC @ 600 ml in 500 l water.Monocrotophos 36SL @ 625 ml in 500-1000 l water.Thiodicarb 75WP @ 468-562 ml in 625 -750 l water.Methyl parathion 2D @ 25 kg/ha.Phenthoate 50EC @ 2000 ml in 500-1000 l of water.Thiacloprid 21.7SC @ 625-750 ml in 375-500 l water/ha. Tur pod bug, Clavigrallagibbosa Spinola (Coreidae :Hemiptera) This insect is widely distributed in Indian subcontinent and adjoining countries. The insect feed on pigeon pea, lablab and cowpea. Both nymphs and adult suck the cell sap from leaves, flower buds and unripe seeds of green pods. As a result of this damage, the pods show pale yellow patches and later on grain shrivel up. The grains inside remains small in size and yield may be reduced significantly. Adult: The adult bugs are light brown in colour, having a spinedpronotum and femur, swollen at the apical end. The bugs are about 20 mm long. The young nymphs are brown in colour and show prominent lateral spines on the prothoracic and abdominal segments.

Eggs: The eggs are usually laid on pods and less frequently on the leaves and floral buds, in clusters of 5-25 each. A female on an average lays 60 eggs during oviposition period in 15 days. The eggs hatch in 8 days and newly hatched nymphs move away from the egg shells within 10-15 minutes and get together at a suitable feeding spot. Nymphs: Nymphs are gregarious in nature and are seen feeding in groups. The nymph takes about 17 days to complete development after passing through five nymphal stages. Life cycle is completed in 21-28 days. The pest is active from the middle of October to the end of May and completes six overlapping generations during this period.

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Management: 1. A minute insect, Hydronotusantestiae Dodd, parasites the eggs of this insect. It has been observed in nature that upto 55 per cent of eggs might be attacked and destroyed. 2. Spray 1.25 litres of monocrotophos 36SL in 750 litres of water per hectare Blue Butterfly, Lampidesboeticus (Linnaeus): (Lycaenidae: Lepidoptera) The larvae of pest cause damage in pigeonpea, Lucerne, Sturt‘s Desert Pea, Rattle Box, English Boom, Hyacinth Bean, Sweet Pea and Garden pea etc. It is small blue coloured butter fly and have wingspan of about 3 cm. The top of wings of the male are blue whereas those of female are blue with wide dark brown edges. Underneath, they both have a brown and white pattern. The adults are dimorphic, the males and females being different. They both have little tail on each hind wing with a pair of small black eye spots beside each tail which are helpful in confusing predators. Egg: The eggs are small, initially pale green and later turn in bluish white, hemispherical, strongly flattened top and bottom, slightly depressed on the top. The short blunt spines are present the side. The egg period is about a week. They are laid singly on the food plant usually on flower buds but sometimes on the open flowers and delicate green parts. Pupa: The full grown larva find a suitable location and crawl to the base of the food plant or simply drop off or descend by silk to the ground and find a suitable place for pupation. This can be among leaf and other debris within or around the base of the plant, beneath or nearby rocks or they can pupate in holes in the ground or soil. In sandy soil, they force themselves into the loose sand to pupate. The pupa is short cylindrical, mostly smooth with a few short bristles near the head, rounded anteriorily and posteriorily and about 10 mm long. Pupa is polymorphic in various shades of brown, pink brown or green brown. The pupation period 10-30 days depending upon the temperature. Spotted pod borer, Marucavitrata (Geyer): (Pyralidae: Lepidoptera) Adult: It is a serious pest of leguminous crops like pigeonpea, cowpea, mungbean, rice bean and soybean. The early instars larvae feeds on flower peduncles and young plant stems while older larvae feed on flower buds, flowers and young pod‘s grain. The adults are creamy white to brown having medium brown wings and long legs. The longevity of male and female is 5-8 days and 6-11 days, respectively. Mating period is with an average 1-3 days. Total life cycle is completed in 20-57 days. Eggs: The eggs are translucent and extremely difficult to see against the background of the oviposition site. Freshly laid eggs are pale yellowish white in colour but turn white at the time of hatching. Incubation period is 2-4 days. The female moth lays eggs either singly or in overlapping groups on the flower buds and flowers surface in large numbers up to 194 eggs. 137

Larva: The larval passes through five instars. The total larval period is 12-15 days. Pupa: Pre-pupal and pupal period last for 1-3 and 6-8 days, respectively. Red gram pod fly, Melanagromyzaobtusa (Malloch) (Agromyzidae: Diptera) This pest occurs wherever pigeonpea is grown in India but most common in northern India. It is small metallic black fly whose tiny maggots bore into the pods and feeds on seeds. The maggots eat away a part of the seed and partially damaged seed becomes subject to bacterial and fungal infections. The damaged grains are thus, rendered unfit for human consumption. Adult: The adult female fly thrusts its minute eggs in to the shells of a tender pods piercing through the ovipositor. Each locule may contain to the maximum 4-5 eggs but normally single egg is found in each locule. A female may lay 60-80 eggs. They hatch in 2-4 days. The maggots feed under the epidermis for some time and then enter the seed. They are full grown in 5-10 days. Pupation takes place inside the damaged pods and the pupal period last in 4-13 days. The adults emerge by cutting holes. The life cycle is completed in 11-27 days.

Management: 1. Spray Azadirachtin 0.03% Neem oil based WSP @ 2500-5000 ml in 500 to 1000 lit water/ha.Monocrotophos 36SL @ 625 ml in 500-1000 l water/ha or Lambda-Cyhalothrin 5EC @ 400-500 ml in 400-600 litWater. Lufenuron 5.4EC @ 600 ml in 500-1000 l water/ha. Spray quinalphos 25EC @ 1400 ml in 500-1000 l water.

Pea stem fly, Ophiomyiaphaseoli (Tryon): (Agromyzidae: Diptera) It is a polyphagous pest and feeds on all types of beans, gram, pigeonpea and pea. It is widely distributed in India, Sri Lanka, Indonesia, Malaysia, Singapore, Philippines, China and African countries. It is very minute insect, body length of the male about 1.9 mm and that the female 2.2 mm. The maggot is creamy white in colour and apodous in form. The larvae are leaf and stem miners. Each female is capable of laying 33 eggs. The slender, white eggs are laid singly in holes made on the upper surface of the young leaves, especially near the petiole end of the leaf. On hatching, the maggots make mines in the leaf and goes towards the main stem. After entering the main stem it feeds on the pith of the stem and goes downwards. The adults also cause damage by puncturing the leaves. The damaged plants turn yellow and bearing capacity of the plant reduced. The damage is more serious on seedlings. The stems turn brown, become swollen and break down. Pupation takes place inside the stem or into the larval galleries. Fresh pupae are yellowish and become dark brown. The pupal period varies from 7-14 days. Management: 1. Remove and destroy all the affected branches during the initial stages of attack. 2. Early sowing of the crop have more damage of the pest. 138

3. Apply chlorantraniliprole 18.5 SC @ 30 ml in 150 lit water for soybean. Black gram/ Green gram/ Pigeonpea: Apply Phorate 10CG @ 10 kg/ha. Leaf miner, Chromatomyiahorticola (Gourea): (Agromyzidae: Diptera) The maggot of this insect feeds between lower and upper epidermis of the leaf by zigzag tunnels/mines on cruciferous plants, pea, linseed, potato, leguminous crops, cucurbits, tomato and lettuce etc. The infested leaves show whitish shinny streaks against the green background. When the damaged leaves are held against bright light, the minute slender larvae can be seen feeding within the tunnels. Large numbers of tunnels made by the maggots interfere with photosynthesis and proper growth of plants. Adults: The adult is a tiny black by with transparent two wings. It has greyish-black mesonotum and yellowish frons. These flies become active from December to April or May. The adults emerge in the beginning of December and after mating it starts egg laying singly in leaf tissues. Egg: The eggs are deposited in leaf tissues. The egg period is 2-3 days. Maggots: The maggots are legless creamy in colour. The larval period is 5 days. Just after hatching the maggots makes mines in the leaves in zigzag manner. Pupa: Pupation takes place in the mines. Pupal period lasts for 6 days. Management: 1. Grow resistant leafless varieties. 2. SprayBacillusthuringiensis var. kurstaki serotype H-3a, 3b strain Z-32 @ 0.75 kg in 500-750 lit water in soybean. Monocrotophos 36SL @ 1000 ml in 500-1000 l water. Limabean pod borer, gold banded moth, legume pod moth: Etiellazinckenella (Treitschke): (Pyralidae: Lepidoptera) It feeds on more than 80 species of cultivated and wild legumes including soybean, pea, lentil, lupine, vetch, Siberian shrub, clover, alfalfa, cowpea, pigeonpea, limabean, mungbean. The larvaefeeds on maturing seeds after entering the pods. Faecal pellets are seen inside the damaged pods. It lives inside the pod and eat away the seeds. The larvae easily pass from one bean to another. Sowing of grain legumes located near forest shelter belts composed of true of false Acacia are mostly damaged. Larvae are generally found infesting maturing and dried pods. Population of this pest build up by the end of the season, when temperature is high. Adult: The moth is quite distinctive with bright creamy yellow coastal streak and a yellowish and chestnut fascia at one third. Body length is 8-11 mm, wing span 19-27 mm and the wings are longer than abdomen which is folded at roof. Forewings are yellow or brown-greyish with characteristics light stripe along fore edges with orange spot on basal third and with dark fringe. Hind wings are light gray with dark venation and dark double line near fringe and fringe is long and light in colour. Top of abdomen is with tuft of golden-yellow hairs. Moths are active during deep twilights and night. Flight of adults begins in May-June. Egg: A female lays maximum 600 eggs one by one in clusters on fully matured pods or on ovaries with dried corolla or green pods. Eggs are laid in 4-21 days. Eggs hatch in 5 days, although, they may take up to 33 days depending upon the climatic conditions. Larva: The newly emerged larvae feed on floral parts and subsequently, they bore into the pods to feed on seeds. The young larvae are green, but becomes pinkish –red as they get older with the body length ranging from 15-22 mm. The larval period lasts in 19-40 days. Larva overwinters within the cocoon in soil at a depth of 2-5 cm.

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Pupa: Pupation takes place in soil at a depth of 2-4 cm. Pupa is brilliant brown, fine punctured to 7-10 mm length, cocoon is thick, white and usually covered with soil particles. The pupal period is 12-18 days. Management: 1. Etiellazinckenella pheromone traps are used to lure and kill the adults and reduce breeding. 2. Sowing of grain legumes at early optimal period at isolation from plantations of true of false Acacia. 3. Apply monocrotophos 36 SL @ 0.04% or chlorpyriphos 20EC @ 3.5 ml/litre of water Aphid, Aphiscraccivora Koch: (Aphididae: Homoptera) Aphids are black in colour with greenish tinge, small viviparous insects, measuring about one tenth to one eight of an inch in length. Colonies of aphid are found on the stems, leaves and pods of leguminous crops. Nymphs and adults suck the cell sap from underside of leaves, top shoots and stems, as a result of it the plants become discoloured and weak. Infestation in the early stage causes stunting of the plants as well as reducing the vigour. The female may produce 8-30 young ones in a life span of 10-12 days. The nymphs transform into adults in 5-8 days after passing through four moults. The apterous female starts producing broods within 24 hours of attaining that stage. The pest breeds throughout the year. The aphids secret honey dew on which sooty mould develop. Females increase at an enormous rate and spread over big area in very short time. The pest is most active in early stages of the crop and damages young ones. This pest also attacks sorghum and other vegetable crops. The aphids appear on kharif leguminous crops in the month of July to September. There are several generations during the rainy season. These insects generally thrive best in the damp weather and when moist wind blows. The economic threshold is 10 per cent infested plants. Management 1. Grow resistant/tolerant varieties. 2. Intercropping with non-leguminous crops such as sorghum or maize which reduces the aphid incidence. 3. Removal of aphid infested tops of the plants at early stage of aphid infestation. 4. The fog, frost, rain, severe heat and cold are the main natural mortality factors of aphids. 5. The predatorsviz., Coccinellids, Syrphids and lace wing and some entomophagous fungi contribute a lot in checking the aphid population. 6. If 10 per cent plants infested, crop may be sprayed with Malathion 0.05% Leafhopper, EmpoascakerriPruthi: (Cicadelidae:Hemiptera) Leafhopper commonly known as jassid is a small size about 12 mm long, delicate and yellowish green insect. Both nymphs and adults suck sap from the leaves, whichin severe cases of attack turn yellow to reddish brown. The attacked leaves later curl up, become distorted and fall down. The nymphs and adults prefer shady areas and generally remain on the lower surface of the leaves. A female hopper lays 30- 50 eggs singly on the underside of leaves, embedding them into the leaf veins. The nymphs emerge from the eggs in 4- 10 days, which are wedge shaped and are very active. Nymphal period lasts for 10 to 20 days. These are light green and fast moving in zigzag manner. The adult stage lasts from 5 to 7 days. The insect passes through 8 to 10 generations in a year. The pest appears during rainy season and attacks throughout the growth stage. Besides leguminous crop it also attacks to guar, Berseem, Lucerne, soybean, potato and tomato crops. Economic threshold for leafhopper is 2 nymphs per leaf based on 30 leaves or 20 per cent fully developed leaves start curling.

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Management: 1. Early sowing escapes leafhopper incidence. 2. Grow resistant varieties. 3. Removal and destroy the weeds as they provide food and shelter to the pest. 4. Balanced use of fertilizers based on soil test. Excessive use of nitrogenous fertilizers attracts more pest. 5. If nymphal population exceeds more than one per leaf spray the crop with 0.05% malathion. Black gram/ Green gram: Phorate 10CG @ 15 kg/ha. In pigeon pea apply of phorate 10CG @ 10 kg/ha Whitefly, Bemisiatabaci (Gennadius): (Aleyrodidae: Homoptera) The female lays eggs singly on the underside of leaves, averaging 120 eggs per female. The eggs are stalked and light yellow at first, turn yellow later on. They hatch in 3- 5 days. Both nymphs and adults feed on cell sap from underside of the leaves and ultimately the crop yield is reduced considerably. Winged adults are 1.0 to 1.5 mm long and their yellowish bodies are slightly dusted with white waxy powder. They have two pairs of pure white wings. The nymphs grow into three stages to form pupae with 9-14 days, the pupae change into adults. The life cycle is completed in 5-10 days and 10 generations are completed in a year. Moreover, whitefly acts as a vector of number of virus diseases. They also excrete honey dew interfering photosynthesis, on which black mould fungi grow. This pest appears more in hot and dry weather conditions. Economic threshold for whitefly is 6 adults per leaf or 20 nymphs per leaf. Management: 1. Grow tolerant varieties of leguminous crops. 2. Use sticky traps or yellow sheets coated with grease for mass trapping whitefly adults. 3. Removal and destroy the weeds as they provide shelter to the pest. 4. The parasitoids, Encarsiaformosa and Eretmocerusmundus contributing a lot in checking the whitefly population. 5. Spray the crop with oxydemeton methyl or dimethoate @ 0.03 per cent. Black gram/ Green gram: Phorate 10CG @ 10 kg/ha Plume moth, Exelastisatomosa(Walshingham): (Pterophoridae: Lepidoptera) It is found in Cape Verde, Ethiopia, Kenya, Madagascar, South Africa, Swaziland, Tanzania, India, Nepal and Iran. It is serious pest of pigeonpea. The larva enters into the pods and feeds on developing grains. It also damages the flowers, flower buds and pods to drop. Hostplant: Leguminous and cucurbitaceous crops.

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Adult: Adult is a small moth with yellowish brown wings measures 7 mm in length and 15 mm wing span. Beautiful greenish brown plume like moth. The forewings are cut into two plumes and hind wings into three. The mean longevity of the adult is 6.59 ± 0.38 days. The female lays about 93-101 eggs in her life cycle. The life cycle is completed in 40-42 days. Egg: The females lay 17- 19 eggs singly on tender parts of the plant. Eggs are dirty white in colour and hatches in 2 to 4 days.Larva: The young larvae feed on the pods and become full grown in 10- 25 days. The larva is greenish-brown and fringed with short hairs and spines. There are five larval instars and full grown larva measures 1.25 cm. Pupa: Pupation takes place on pod surface or entrance hole or in burrow of infested pods and pupal period is 7- 9 days. Management: 1. Collect and destroy larvae and pupae. 2. Spray monocrotophos 36SL @ 625 ml in 500-1000 l water in red gram or carbaryl 10 DP@ 2000 ml in 20,000 lit water. Fieldbeanpod borer, Adisuraatkinsoni The larva feeds on flower buds, opened flowers, tender and mature pods. It bores inside the pod and feeds on the seeds within. Adult: Adult moths are yellowish brown in colour. Forewings are yellow with V shaped specks and hind wings have pale brown markings. Eggs: The single female lays about 413 eggs. The incubation period is 3-5 days. Larva: The larva is green colour having brown lateral markings. It has humped anal segment. Old larvae show lateral brown stripes and yellow to green colour. The head is brown to black. The larva passes through six instars. Larval period is 17-22 days. Pupa: The pre-pupal period is 2.15± 0.16 days, whereas pupal period is 13.15± 0.27 days Management: 1. Put 50 bird perches per hectare. 2. Mechanical collection of grown up larvae. 3. Deep summer ploughing in 2-3 years to eliminate quiescent pupae. 4. Early sowing of the crop with short duration varieties. 5. Avoid closure spacing. 6. Grow tall varieties of sorghum which will serve as biological bird perches 7. Install pheromone traps at a distance of 50m @ 5 traps/ha. 8. Setting of light traps to kill moth of the insect. 9. Spray triazophos 0.05% or quinalphos 25EC @ 1000 ml/ha. Objective type questions related to this lecture:1. Butterfly attacking on pulses crop? a. H. armigera c. L. boeticus 2. a. c.

b. d.

Pigeonpea sterility mosaic transmitted by Aphids b. Mite d.

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E. atomosa A. atkinsoni

Whitefly Thrips

3. a. c.

Pinhole on pods with galleries on seeds in pigeonpea is attacking symptom of which pest? Plume moth b. Pod fly Pod borer d. Thrips

4. a. c.

Pinhole with shriveled grains in pods of pigeonpea is attacking symptoms of Plume moth b. Pod fly Pod borer d. Pod bug

5. a. c.

Which is the larval parasitoid of gram pod borer in field condition at earlier stage? Campolestischloridae b. Trichogramma spp. Chrysoperla d. Coccinellaseptampunctata

6. a. c.

Which pest of gram feeds on pods by thrusting its head into the pod? Plume moth b. Pod fly Pod borer d. Thrips

7. a. c.

Which pest of gram attack on both stored grain and field? Pod fly b. Pulse beetle Khapra beetle d. Blue butterfly

8. a. c.

Pest of pulses where external symptoms not seen Blue butterfly b. Pulse beetle d.

Pod fly Thrips

9. a. c.

Pest of pulses which pupate inside the pod Pod borer b. Pulse beetle d.

Pod fly Thrips

10. a. c.

Pest of pulses which pupate inside the seed Pod borer b. Pulse beetle d.

Pod fly Thrips

11. a. c.

Which is the damaging stage of blister beetle Egg b. Nymph d.

Adult Larva

12. a. c.

Irregular or round leaf mines on pulses leaves are due to attack of Leaf miner b. Pod bug Blister beetle d. Leaf eating caterpillar

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13. a. c.

Soybean stem girdler lays eggs on Leaves Stem

14. a. c.

Use of marigold as trap crop is practiced for the control of which pest? Plume moth b. Pod fly Pod borer d. Thrips

15. a. c.

Which microbial pesticide is used against gram pod borer SlNPV AcNPV

16. a. c.

The whole ground nut field presents a burnt appearance because of severe attack of which pest Leaf miner b. White grub Pod borer d. Red hairy caterpillar

17. a. c.

The pest of ground nut when severely attacked gives the appearance as if it is grazed by cattle is Leaf miner b. White grub Pod borer d. Red hairy caterpillar

18. a. c.

Number of generation completed in one year by white grub is/are One b. Three d.

Two Four

19. a. c.

Soybean spotted wilt virus transmitted by Whitefly Aphid

b. d.

Thrips Mealybug

20. a. c.

Pulses yellow mosaic transmitted by Whitefly Aphid

b. d.

Thrips Mealybug

b. d.

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b. d.

Soil Pods

HaNPV None of the above


MAJOR INSECT PESTS OF OILSEEDS AND THEIR MANAGEMENT SP Singh Department of Entomology CCS HAU Hisar In India, oilseeds occupy a prominent place with a production o f 25.6 million tonnes from an area of 17.51 million ha in 2012-13. These crops are damaged by a number of pests, of which some are more serious. These pests can be effectively controlled by the use of various safe insecticides / bio-pesticides in addition to use of some cultural practices and pest tolerant varieties. On the basis of information available, various practices have been suggested to evolve strategy to develop IPM approaches against major pests in oilseed crops. Such IPM approaches will help to increase the production and productivity of these crops by reducing the pest damage without any adverse effect on the agro- system and erosion in the environment. Pest wise information and management of major pests infesting oilseed crops are described below. BRASSICA CROPS Mustard aphid, Lipaphis erysimi The mustard aphid is worldwide and is a serious pest of cruciferous oilseeds like toria, sarson, raya, taramira and Brassica vegetables like cabbage, cauliflower, knol-khol, etc. The aphids are minute, soft-bodied and light green insects having a pair of short tubes called cornicles on the postero-dorsal region of the abdomen. Life cycle: The insect breeds partheno-genetically and the females give birth to 26-133 nymphs. They grow very fast and are full-fed in 7-10 days. About 45 generations are completed in a year. The winged forms are produced in autumn and spring, and they spread from field to field and from locality to locality. Damage: Both the nymphs and adults suck cell sap from leaves, stems, inf lorescence or the developing pods. Due to the very high population of the pest, the vitality of plants is greatly reduced. The leaves acquire a curly appearance, the flowers fail to form pods and the developing pods do not produce healthy seeds. The honeyd ew excreted by the aphids provides congenial conditions for the growth of sooty mould on the plant. In case of severe infestation the crop yield may be reduced by even 80 per cent or more. Management: Early sowing reduces the incidence of mustard aphid at many locations in India. Three rounds of manual removal (clipping) of aphid infested twigs at 15 day intervals starting with the first appearance of the pest have been found effective if cheap labour is available. Apply any one of the following insecticide s when the population of the pest reaches 13-15 aphids per 10 cm terminal portion of the central shoot or when an average of 0.5-1.0 cm terminal portion of central shoot is covered by aphids or when plants infested by aphids reach 20 per cent: (i) Foliar sprays. 250 ml of oxydemeton methyl 25 EC or 250 ml dimethoate 30 EC or 250 ml malathion 50 EC (when crop grown for Saag purpose) in 250 litres of water per acre. 145

Painted bug, Bagrada cruciferarum The painted bug is a serious pest of cruciferous crops and is widely distributed in Myanmar, Sri Lanka, India, Iraq, Arabia and East Africa. Besides cruciferous crops, it has also been observed feeding on rice, sugarcane, indigo and coffee. The full -grown nymphs are about 4 mm long and 2.66 mm broad. They are black with a number of brown markings. The adult bugs are 3.71 mm long and 3.33 mm broad. They are sub ovate, black and have a number of orange or brownish spots. Life cycle: These bugs lay oval, pale-yellow eggs singly or in groups of 3-8 on leaves, stalks, pods and sometimes on the soil. A female bug may lay 37-102 eggs in its lifespan of 3-4 weeks. The eggs hatch in 3-5 days during summer and 20 days during December. The nymphs develop fully in five stages and transform themselves into adults in 16-22 days during the summer and 25-34 days during the winter. The entire life-cycle is completed in 19-54 days and it passes through 9 generations in a year. Damage: The painted bug appears at two stages of crop growth i.e. seedling and mature/harvesting and many times infestation is carried even to threshing floor. Both nymphs and adults suck cell sap from the leaves and developing pods, which gradually wilt and dry up. Severe attack at seedling stage may even kill the plants. The nymphs and adult bugs also excrete a sort of resinous material, which spoils the pods. Management: Clean cultivation and quick threshing of harvested crop helps in lowering the incidence of the pest. If painted bug is a regular pest, treat one kg seed with 5 gm Imidacloprid 70 WS or 5 gm Thiamethoxam 25 FS. If one nymph or one adult is present in one meter row length of the crop area, spray the crop with 200 ml malathion 50 EC in 150-200 litres of water per acre depending on the stage of the crop. GROUNDNUT Ground aphid, Aphis craccivora This is one of the most serious pests of groundnut. It also attacks peas, beans, pulses, safflower and some weeds. Its distribution is throughout India. It has also been recorded in Africa, Argentina and Chile. The winged adults are soft -bodied insects with black wings and they reach the freshly germinated groundnut plants after over -wintering on collateral host plants. Life cycle: Even without fertilization the females may produce 8-20 young ones in a life span of 10-12 days. The young nymphs are brownish and they pass through four moults to become adults in 5-8 days. The apterous females start producing brood within 24 hours of attaining that stage. Breeding occurs almost throughout the year and both alatae and apterae are present. The coccinellid beetle, Coccinella septempunctata (Coleoptera: Coccinellidae) and syrphid fly, lschiodon javana (Wiedemann) (Diptera: Syrphidae) are the main predators of this pest. Damage: The nymphs and adults suck the sap, usually from the underside of leaves. Infestation in the early stages causes stunting of the plants as well as reducing their vigour. When the attack occurs at the time of flowering and pod formation, the yield is reduced considerably. Infestation on the groundnut crop usually occurs 4 -6 weeks after sowing. The aphid is also vector of rossette disease of groundnut. Management: As soon as the pest appears on growing points, spray 200 ml of malathion 50 EC in 200 litres of water per acre.

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White grub, Holotrichia consanguinea The insect appeared as a pest of groundnut in 1957 in the Gujarat State and is now distributed in U.P., Bihar, Haryana, Himachal Pradesh, Rajasthan and Punjab. The grubs when full grown are about 35 mm long and are white, having a brown head and prominent thoracic legs. The adults beetles are dull brown and measure about 18 mm in length and 7 mm in width. Life cycle: The adult beetles lay eggs singly up to a depth of 10 cm. The eggs hatch in 7-10 days. The newly hatched grubs measure about 12 mm in length and their development is completed in 8-10 weeks. After the monsoon, the full-grown larvae migrate to a considerable depth in the soil for pupation. The pupa is semicircular and creamy white and the pupal stage lasts about a fortnight. The beetles remain in the soil at a depth of 10-20 cm and come out for feeding at night. Adults formed in November remain in soil till next June. Their population is maximum in the rainy season and there seems to be only one generation in a year. Damage: The grubs eat away the nodules, the fine rootlets and may al so girdle the main root, ultimately killing the plants. At night, the beetles feed on foliage and may completely defoliate even trees like neem (Azadirachta indica) and banyan (Ficus bengalensis). Management: (i) Plough the fields twice during May-June. It would help in exposing the beetles resting in the soil. (ii) Treat the seed before sowing with 15 ml of chlorpyriphos 20 EC or 15 ml quinalphos 25 EC per kg of kernels and this seed treatment will also control the termites in groundnut crop. (iii) Kill t he beetles by spraying the trees @ 0.05% carbaryl 50 WP or 0.05 % quinalphos 25 EC or 0.4% monocrotophos 36 SL in 250 litres of water after rainfall on the preferred host plants like ber, guava, rukmanjani, grapevines, almond, etc. The spray should be carried out in the afternoon and repeated after every rainfall till the middle of July. CASTOR Castor semilooper, Achaea janata This is a serious pest of castor in all parts of India and Pakistan and has also been reported from Sri Lanka and Thailand. The adult of A. janata is a pale reddish brown moth with a wing expanse of 6-7 cm. The wings are decorated with broad zig-zag markings, a large pale area and dark brown patches. The full grown larva is dark and is marked with prominent blue-black, yellow and reddish stripes. Life cycle: A female lays up to 450 eggs during its life span. The egg, being about 1 mm in length, is fairly large and also has on its surface a few ridges and furrows which radiate from the circular depression at the apex. The larva emerge s by cutting a hole in the egg-shell in 2-5 days and devours it immediately. The larva feeds and moults 4 -5 times and becomes full-grown in 15-20 days. The grown-up larva prepares a loose cocoon of coarse silk and some soil particles, and pupates under the fallen leaves on the soil, usually at the edge of the field. In some cases, pupation also takes place within the folded leaves on the plant itself. The pupal stage lasts 10 -15 days and the moths, on emergence, feed on the soft fruits of citrus, mango, etc . There are 5-6 generations in a year. Damage: The caterpillars feed voraciously on castor leaves, starting from the edges inwards and leaving behind only the midribs and the stalks. With the excessive loss of foliage, the seed yield is reduced considerably. 147

Management: Spray 1 kg of carbaryl 50 WP in 250 litres of water per acre and repeat at 15-day intervals, if pest persists. Castor hairy caterpillar, Euproctis lunata The castor hairy caterpillar is widely distributed in India particularly in Uttar Pra desh, Orissa, Haryana, Madhya Pradesh, Andhra Pradesh, Karnataka and Tamil Nadu. It has also been observed feeding on linseed, groundnut and grapevine. Full -grown larvae are dark grey, with a wide white dorsal stripe, and have long hair all over body. The moths are pale yellow. Life cycle: Moths lay a large number of eggs in clusters on the underside of leaves. The eggs are covered with the female anal tuft of brown hair. They hatch in 5 -7 days and the young larvae feed gregariously for the first few days. Later on, they disperse and feed individually. They pass through six stages and are full-fed in 2-3 weeks. The full-grown caterpillars make loose, silken cocoons in the plant debris lying on the ground and pupate inside. The pupal stage lasts about one week in the summer. During the winter months, the egg, larval and pupal stages may last 10, 85 and 20 days, respectively. The pest passes through several generations in a year. Damage: Caterpillars feed on the leaves of various host plants and in case of sev ere infestation, they may cause complete defoliation. The attacked plants remain stunted and produce very little seed. Management: i) Deep ploughings, destroying the weeds and use of light traps help in reducing the population of this pest. ii) Kill the eggs and first phase larvae. iii) Spray the crop with 250 ml monocrotophos 36 SL or 200 ml diclorvos 76 EC or 500 ml quinalphos 25 EC in 250 liters of water per acre. SESAME Til leaf and pod caterpillar, Antigastra catalaunalis The sesame leaf and pod caterpillar is a serious and regular pest of til (Sesamum orientale and S. indicum) and is also distributed throughout India. This species has also been reported from Europe, Africa, Cyprus, Malta, Indonesia and South -cast Africa. The caterpillars are pale yellow, when young, but gradually become green and develop black dots all over the body. The full-grown larva measures 14-17 mm. The moth is a small insect with a wing span of about 2 cm having dark brown markings on the wing tips. Life cycle: Females lay up to 140 eggs singly on the tender portions of plants at night. The eggs arc shiny, pale-green and they hatch in 2-7 days, depending upon the season. On emerging, the young larva, which measures about 2 mm in length, feeds for a little while on the leaf epidermis or within the leaf tissue. Soon after, it binds together the tender leaves of the growing shoot with the help of silken threads and continues to feed in the webbed mass. The size of this rolled mass increases gradually as the caterpillar grows older. It becomes full-grown in about 10 days in summer, but the period may be .prolonged to 33 days in winter. The grown-up larvae creep to the ground and pupate in silken cocoons in soil. Sometimes, pupation also takes place in the plant itself. Pupal development is completed in 4-20 days, depending upon the season. In summer, a generation is completed in about 23 days but in the winter it takes about 67 days. Damage: Young caterpillars feed on leaves. They also bore into the shoots, flowers, buds and pods. An early attack kills the whole plant, but infestation of the shoots at a later stage hampers further growth and flowering. 148

Management: Spray the crop thrice with 600, 650 and 725 gm carbaryl 50 WP at pest appearance, flowering and pod formation in 200, 220 and 240 liters of water per acre. LINSEED, (Linum usitatisimum) Linseed gall-midge, Dasineura lini This insect appears as a serious pest of linseed in some parts of India, including Andhra Pradesh, Madhya Pradesh, Bihar, Uttar Pradesh, Delhi and Punj ab.The adult is small delicate, mosquito like orange coloured insect. Life cycle: The female lays 29-103 smooth, transparent eggs in the folds of 8-17 flowers or in tender green buds, either singly or in clusters of 3 -5. The eggs hatch in 2-5 days. Just after emergence, the larvae are transparent, with a yellow patch on the abdomen. These larvae feed inside flower buds and eat the contents. They pass through four instars in 4-10 days and when full-grown become deep pink and measure about 2 mm in length. The full-grown maggots drop to the ground, prepare a cocoon and pupate in the soil. The pupal period lasts 4-9 days. A generation is completed in 10-24 days. There are four overlapping generations during the season. Damage: Damage is the result of feeding by maggots on buds and flowers. Consequently, no pod-formation takes place. Management: (i) The adult flies can be killed by using light traps. The flies are also attracted in day-time to molasses or gur added to water. (ii) As the incidence of this pest is more on the late-sown crop as compared with the normal-sown crop, the practice of normal-sown crops should be adopted if possible. iii) If pest incidence is more 10 per cent then spray the crop with 600 gm carbaryl 50 WP in 200 liters of water per acre. SUNFLOWER (Helianthus annus) Head borer, Helicoverpa armigera The head or capitulum borer causes considerable damage to developing grains in the head capsule. The young larvae first attack the tender parts like bracts and petals, and later on shift to reproductive parts of the flower heads. Bigger larvae mostly feed on seeds by making tunnels in the body of the flower heads and often remain concealed. They may also shift to the backside of the heads and even leaves, and feeding may continue upto maturity. Star bud stage of the crop is most vulnerable and suffers maximum yield loss. The detailed account of life of the pest has been given in chapter 10. Management: Early sown crop usually suffers lower attack of the pest. In case of severe attack especially on late sown crop, when one larva per plant, average of 20 plants is present, spray the crop with 600 ml of quinalphos 25 EC in 200 liters of water per acre at the initiation of star bud stage, and repeat after two weeks if necessary. REFERENCES Bakhetia, D.R.C. and Sekhon, B.S. 1989. Insect-pests and their management in rapeseedmustard. J. Oilseeds Res., 6 (2): 269-299. Chander, S. and Phadke, K.G. 1994. Economic injury levels of rapeseed aphid, Lipaphis erysimi determined on natural infestation and after different insecticides treatments. Intern. J. Pest Manag., 40:107-110.

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Kalra, V.K., Gupta, D.S. and Yadav, T.P. 1983. Effect of cultural practices and aphid infestation on seed yield and its component taits in Brassica juncea (L.) Czern and Coss. Haryana agric. Univ. J. Res., 13:115-120. Nain, Rohit, Dashad, S.S. and Singh, S.P. 2009. Relative efficacy of newer insecticides against pod borer, Helicoverpa armigera (Hubner) infesting sunflower crop. Proc. National Symposium on role of pesticide application technology in crop protection: towards sustainability in agriculture.20-22 January, 2008 organised by Institute of Pesticide Formulation Technology,Gurgaon, India.pp.61-62 Singh, H.1982. Studies on insect-pest complex in Brassica campestris L. var. brown ‗sarson‘. Disserertation, Doctor of Philosophy, Entomology, submitted to Haryana Agricultural University, Hisar, 192 pp. Singh, S.P. 2009. Population dynamics and monitoring techniques for aphid in rapeseed mustard. Proc. Advanced Training Course on recent advances in pest population dynamics and monitoring techniques. 17th February to 9th March, 2009, organized by Department of Entomology, CCS Haryana Agricultural University, Hisar, India. pp. 95-98 Singh, S.P. 2009. Insect pest management in oilseed crops. Indian farming. 58(7): 29-33.

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MAJOR INSECT- PEST OF FORAGES AND THEIR MANAGEMENT SP Singh Department of Entomology CCS HAU Hisar In India, the cultivated fodder crops include plant species such as sorghum, Egyptian clover (berseem), lucerne, maize, pearl millet (bajra), oats, cowpea, clusterbean (guar) and several other grasses. Among these, sorghum, cowpea, clusterbean (guar), maize and pearl millet are mainly grown in kharif season while Egyptian clover (berseem), lucerne and oats are major rabi crops. Insect pests are one of the major constraints in increasing and stabilizing the production and productivity of forage crops. A number of insect pests inflict moderate to sever quantitative and qualitative losses to these crops. Pest wise information about biology, bionomics and nature of damage of major pests infesting forage crops and their management approaches are described below. I. SORGHUM a) Shoot Fly The shoot fly is a serious pest of sorghum in early stages (upto four weeks after germination) of crop growth and is also a minor pest of maize and bajra. Shoot fly females lay cigar-shaped whitish eggs singly on the lower surface of the leaves at seedling stage almost during morning hours. Eggs hatch in 1 to 2 days, and the larvae move along the shoot to the growing point. The first-instar larva cuts the growing point, which results in wilting and drying of the central leaf, known as a dead heart. The dead heart produces a bad smell and it can be pulled out easily. Normally, the damage occurs at one week to four weeks after seedling emergence. The damaged plants produce side tillers, which may also be attacked further. Larval development is completed in 8 to 10 days and pupation takes place mostly in the soil. The pupal period lasts for 8-10 days. The entire life cycle is completed in 17 to 21 days. In northern India, there are two distinct peaks of shoot fly activity i.e., during March to mid May and mid July to September. The avoidable yield losses and due to this pest in forage sorghum is about 30 per cent. Economic threshold for shoot fly is 20 per cent dead hearts or 5 per cent plants with eggs, 10 days after germination. Management Approaches  Grow the least susceptible forage sorghum variety, HC 171 during mid May to June to avoid heavy incidence of shoot fly.  Use 10 per cent high seed rate.  Intercrop of sorghum with non-host crop like cowpea to reduce the damage of shoot fly.  Removal and destruction of plants with dead hearts and eggs at 10 days after crop emergence.  Grow multicut forage sorghum variety, SSG 59-3 to reduce the shoot fly incidence.  If necessary, spray the crop with 0.1% carbaryl 50 W.P. at 10 days after crop 151

germination. b) Stem Borer It is a major pest of sorghum and attacks all stages of crop growth after 15 days of germination. The stem borer also damages maize and bajra crops. The larvae that hatch in about a week and migrate to plant whorl causing leaf injury and dead heart formation. Tunnelling by larva in stem reduces the plant vigour and yield as well as the fodder quality. The larval period is about 18 – 24 days. It pupates inside the stem and emerges as adult in about 7 days. The total life cycle is completed in 35 to 42 days. In northern India, larvae go under hibernation from November to February and it was observed that sorghum stalks, stubbles and ear heads harboured 67.4, 25.1 and 7.5 per cent of the hibernating stem borer larvae, respectively. This population is the source of initial infestation in the subsequent season. Therefore, destroying the stubbles can considerably reduce the pest population and chaffy stalks feeding to the cattle before the start of next season. The avoidable losses due to stem borer in forage sorghum have been estimated about 40 per cent. It also reduces the quality of forage sorghum and it has been estimated that about 16 per cent reduction is there in terms of in vitro dry matter digestibility (IVDMD) due to stem borer infestation. Economic threshold value for the stem borer is 10 per cent dead hearts 20 days after germination in sorghum. Management Approaches  Destroying the stubbles, weeds and other alternate hosts by ploughing the fields after harvest may reduce the potentials of carryover.  Use 10 per cent high seed rate to avoid the yield losses.  Removal and destruction of dead hearts and destruction of infested plant parts showing early pin holes damage has been found to be effective in reducing the pest incidence.  Destruction of crop residue and chopping of stem harbouring diapausing larvae.  Grow the sorghum with cowpea to reduce the damage of stem borer.  Grow the multicut and tolerant forage sorghum variety, SSG 59-3 to reduce the pest damage.  If necessary, spray the crop with 0.1% carbaryl 50 W.P. after 20 days of crop germination and repeat second spray after 10 days. Based on available information, judicious application of different methods in an integrated manner can be recommended as mention below in such a way so as to bring pest incidence below economic injury level in forage sorghum. Integrated Pest Management (IPM) Module in Forage Sorghum 0. Take up sowing during mid May to June so as to avoid the heavy incidence of shoot fly and stem borer. 1. Intercultures of sorghum with non-host crop like cowpea to reduce the damage of shoot fly and stem borer. 2. Uproot the seedlings infested due to shoot fly and stem borer and destroy them to reduce the multiplication of the pests. 3. Increase seed rate 10 per cent and remove the dead heart plants so as to tolerate the damage due to shoot fly and maintain optimum plant population. 4. Destroying the stubbles, weeds and other alternate hosts by ploughing the fields after harvest may reduce the potentials of pest carryover. 5. Plough the field soon after harvest of the crop so as to expose the larvae and pupae of stem borer. 152

6. Grow multicut forage sorghum variety, SSG 59-3 to reduce the shoot fly and stem borer incidence. 7. Use resistant / tolerant varieties. 8. Use recommended insecticides in case the pest intensity crosses the Economic Threshold. i) Economic threshold for shoot fly is 20 per cent dead hearts or 5 per cent plants with eggs, 10 days after germination. If necessary, spray the crop with 0.1% carbaryl 50 W.P. at 10 days after crop germination. ii) Economic threshold value for the stem borer is 10 per cent dead hearts 20 days after germination in sorghum. If necessary, spray the crop with 0.1% carbaryl 50 W.P. at 20 days after crop germination and repeat second spray after 10 days. II. COWPEA AND CLUSTERBEAN a) Aphid Colonies of aphids are found on the stems, leaves, and pods of cowpea and guar plants. Nymphs and adults suck sap from underside of the leaves, top shoots and stems, as a result of which the plants become discoloured and weak. Infestation in the early stage causes stunting of the plants as well as reducing the vigour. Management Approaches  Early sowing of cowpea and clusterbean crops escapes the aphids incidence.  Grow improved / tolerant cowpea and clusterbean varieties, CS 88, GC3 and HG 365, HG 563, respectively.  Intercropping with non-leguminous crops such as sorghum and maize reduces the aphids incidence in cowpea and clusterbean crops.  Removal of aphid infested tops of the plants, at early stage of aphid infestation.  The fog, frost, rain, severe heat and cold are the main natural mortality factors of aphids.  The predators viz., Coccinellids, syrphids and lace wing and some entomogenous fungi viz., Entomophthora and Cephalosporium contributing a lot in checking the aphid population.  If 10 per cent plants infested, crop may be protected from aphids by spraying 0.05 per cent malathion. b) Leafhopper The pest appears on these crops during the rainy season and attacks through out the growth stage. Besides cowpea and guar, it also attacks berseem, lucerne, soybean, potato and tomato crops. Economic threshold for leafhopper is 2 nymphs per leaf based on 30 leaves or 20 per cent fully developed leaves start curling. The avoidable losses due to this pest in cowpea and clusterbean seed crops are about 30 per cent. Management Approaches  Early sowing of cowpea and clusterbean crops (up to first week of June) escapes leafhopper incidence.  Grow resistant cowpea and clusterbean varieties, CS 88, GC 8927 and HG 75, HG 884, respectively.  Removal and destroy the weed as they provide food and shelter to the pest.  Use balanced fertilizers based on soil test. Excessive use of nitrogenous fertilizers attracts more pests.  If nymphal population exceeds more than one per leaf, spray the crop with 0.05 per cent malathion. c) Pod Borer The young larva feeds on the foliage for some time and later damages the flower buds, 153

pods and feed on the developing grains and can reduce the seed yield up to 60 per cent. A single larva may destroy 30-40 pods before it reaches maturity. Characteristically, while feeding, the head will be thrust inside leaving rest of the body outside. Management Approaches  Grow early maturing, short duration and tolerant varieties of cowpea and clusterbean, CS 88, GC 13 and HG 365, HG 563, respectively.  Removal and destroy the crop stubbles/remnants as they serve as initial source of infestation.  Removal and destroy the weed as they provide food and shelter to the pest.  Use balanced fertilizers based on soil test. Excessive use of nitrogenous fertilizers attracts more pests.  Use pheromone and light traps to monitor and collect male moth population.  Release egg parasitoid, Trichogramma chilonis @ 3 lakh adults/ha and larval parasitoid, Campolestis chloridae Uchida to manage this pest in field conditions.  Spray the crop with 0.1% carbaryl 50 W.P. to control this pest effectively and second spray can be done 10 days after, if pest persists.  Neem based insecticide like nimbecidine is also effective, which acts as antioviposition (repellant) and antifeedant against this pest. Integrated pest management module in cowpea and clusterbean crops:  Grow early maturing, short duration varieties of cowpea and clusterbean during June so as to avoid the heavy incidence of insect pests.  Destroying the stubbles, weeds and other alternate hosts by deep ploughing the fields after harvest may reduce the potentials of pest carryover.  Use balanced fertilizers based on soil test. Excessive use of nitrogenous fertilizers attracts more pests.  Release of parasitoids to manage different pests at proper time.  Use resistant/tolerant cowpea and clusterbean varieties, particularly CS 88 and HG 75, respectively which having multiple resistance against major pests.  Use recommended insecticides if pest intensity crosses the economic threshold. III. EGYPTIAN CLOVER (BERSEEM) The young larva feeds on the foliage for some time and later damages the flower buds, pods and feed on the developing grains and can reduce the seed yield up to 60 per cent. A single larva may destroy 30-40 pods before it reaches maturity. Management Approaches  Grow berseem genotypes, HFB 600 and HFB 101 which showed minimum damage and tolerant to Helicoverpa armigera.  Destroying the stubbles, weeds and other alternate hosts by deep ploughing the fields after harvest may reduce the potentials of pest carryover.  Use balanced fertilizers based on soil test. Excessive use of nitrogenous fertilizers attracts more pests.  In berseem seed crop, spraying with 0.1% carbaryl 50 W.P. 10 days after last cut of berseem, can control this pest effectively and second spray can be done 10 days after, if pest persists.  Neem based insecticide like nimbecidine is also effective; act as antioviposition (repellant) and antifeedant against this pest. 154

IV. OATS a) Armyworm It is an occasional pest but it become serious when appears on the crop. The moths lay round green colour eggs singly in rows or in cluster on dry and fresh leaves. Freshly emerged larvae are very active and feed on older leaves. The larvae severely feed on the leaves which leads to extensive defoliation and occasionally cut the peduncle which result in total seed loss. The larvae remain active in the field during January to April. Pupation takes place in the soil and also under dry leaves. Generally, the outbreak of army worm occurs after heavy rains and floods. The larvae feed voraciously and migrate from one field to another. The young larvae eat the leaves in the central whorl of the plant. The yield losses due to this pest were up to 25 per cent, when the pest appeared on the crop. Management Approaches  Clean cultivation and lower plant population help in reducing insect damage.  Destroying the stubbles, weeds and other alternate hosts by deep ploughing the fields after harvest may reduce the potentials of pest carryover.  Use balanced fertilizers based on soil test. Excessive use of nitrogenous fertilizers attracts more pests.  If necessary, spray the crop with 0.1% carbaryl 50 W.P. V. LUCERNE a) Lucerne weevil The lucerne weevil is a serious pest of fodder lucerne. The adult weevils are nocturnal in habit. Both adults and grubs feed on the growing leaf buds and leaves causing stunting of the plants. The females lay about 40-50 round yellowish eggs singly into the stem and on tender shoots. The grubs become full-grown in about 30 days and cocoons in between two leaves. The adult emerges in about 10 days. The total life cycle takes about 50 days and only one generation in a year. This pest is more active from January to April and reduces about 25 per cent green fodder yield. This pest is also damage to senji and metha fodder crops. Management Approaches  Frequent cutting of lucerne during January to April helps in reduction of pest damage.  Grow the lucerne tolerant variety, T-9 to reduce the green yield losses.  Removal of lucerne weevil infested tops of the plants, at early stage of pest infestation.  Clean cultivation and lower plant population help in reducing insect damage.  Destroying the stubbles, weeds and other alternate hosts by deep ploughing the fields after harvest may reduce the potentials of pest carryover.  Use balanced fertilizers based on soil test. Excessive use of nitrogenous fertilizers attracts more pests.  If 10 per cent plants infested, crop may be protected from lucerne weevil by spraying with 0.1% carbaryl 50 W.P. REFERENCES Sharma, H.C. 1985. Strategies for pest control on sorghum in India. Tropical Pest Management, 31:167-185. Sharma, H.C. and Nwanze, K.F. 1996. Insect pests of sorghum and their management. ICRISAT, Patancheru, India. p.29. Singh, S. P. 2004. Pest management strategies in clusterbean. Pages: 112-120 in Guar (Eds. J.V. Singh and B.S. Dahiya), Forage Research Society, CCS HAU, Hisar, India. Singh, S.P. 2000. Insect pest management in forage crops. Proc. Advanced Training Course on 155

Recent Advances in Integrated Pest Management. 1-21, December, 2000, Department of Entomology, CCS Haryana Agricultural University, Hisar, India.pp. 283-292. Singh, S.P. 2004. Role of beneficial insects in forage crops. Proc. Advanced Training Course on Advances in management of beneficial insects. 24th February to 15th March, 2004, Department of Entomology, CCS Haryana Agricultural University, Hisar, India. Singh, S.P. 2005. Advances in the integrated pest management of cowpea, clusterbean and other vegetable beans. Proc. Advanced Training Course on Advances in the integrated pest management of Horticultural, Spices and Plantation Crops. 21st December, 2004 to 10th January, 2005, Department of Entomology, CCS Haryana Agricultural University, Hisar, India. pp. 116-119. Singh, S.P.2006. Insect – pest management in forage crops. Indian Farming. 85(5): 42-46

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LATEST TRENDS IN PEST MANAGEMENT IN VEGETABLE CROP SS Sharma Depatmentof Entomology CCS. HAU Hisar The total Area Under Vegetable crops in India is App.7.5 million ha and the production is about 97.5 M T. The Insecticide consumption on vegetable crops is 13% of total insecticides. The area of veg crops under plant protection umbrella is about 20 per cent. The loss due to pests in vegetable crops varies from 30-40 per cent. The average loss crop wise is as in Brinjal 40.4, Tomato 22.3, Okra 20.0, Pea 19.2 and in Potato 36.9 per cent. Economic threshold of pests Pest

Parameters

Okra hoppers

leaf

4.66 nymphs per leaf 3 nymphs per leaf ), 2 nymphs per leaf

fruit& borer

fruit

5.3 % infestation of fruits, One infested plant per meter row.

Chilli mite

One mite per leaf

Chilli thrips

2 thrips per leaf

Crop/Pest

Parameters

Diamondback moth (Plulella xyloslella) on cabbage

20 larvae/plant 74 (3/4 instar) larvae/plant in seedling stage 10 (3/4 ins tar) larvae/plant in one month after transplanted crop 20 (3/4 instar) larvae/plant in 12 months after transplanted crop 2 larvae/plant at 1-4 weeks after transplanting (WAT) 5 larvae/plant at 5-10 WAT

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Radish aphids (Lipaphis erysimi) (seed crop) Cut worms (Agrolis ipsilon) on potato Okra fruit borer (Earias vittella) Pea aphids (Acyrlhosiphon pisum) Cabbage leaf webber {Croeidolomia binolalis} Tomato fruit borer (Helieoverpa armigera)

75 aphids/plant One larva/lO plantS„ 5.3 % infestation of fruits 3-4 aphids/stem tip 0.3 egg mass/plant 8 eggs/15 plants or one larval/ plant

PESTS OF OKRA GREEN LEAFHOPPER, SHOOT AND FRUIT BORER, WHITEFLY,BLISTER BEETLE and RED SPIDER MITE OKRA LEAFHOPPER (Amrasca biguttulla biguttulla): Nymphs and adults suck, sap from lower surface of leaves inject toxic saliva. Infested leaves turn yellow and curl upwards and become cup shape. In case of severe infestation, the leaves become brick red, brittle and finally drop down. Active throughout the year except in severe winter. SHOOT AND FRUIT BORER IN OKRA (Earias spp) Nature of Damage: larvae bores into tender shoots and tunnel downward, growing tip is killed, shoot droops down and side shoots emerge, caterpillars bore in the flower buds and fruits feed on the developing seeds. heavy loss in seed prod.Damaged buds droop down and fruits curve at injury point damaged fruit unfit for use. (E.T.): 1 infested plant per meter. BLISTER BEETLE (Mylabris pustulata): Beetle is dark red in colour with black spots on forewings. lay eggs in soil and its grubs feed on eggs of grasshoppers in soil. Beetles are only feeding stage .They feed on flower petals, anthers, scratch the fruits. Mealy bug (Phenacoccus solenopsis Tinsley): Both nymphs and adults suck the cell sap from the lower side of the leaves or from the shoots. Infested plants remain stunted or finally dry away. Under severe infestation there happens a heavy loss to the crop. The male adults are not harmful to the crop. Red spider mite (Tetanychus urticae): Larvae, nymphs and adults suck cell sap. Minute white spots appear on the leaves. Large-scale webbing on the leaves, creates hindrance in normal growth. Polyphagous pes , active from March to October. INSECT PESTS OF BRINJAL Shoot and fruit borer (Leucinodes orbonalis) : Egg cream coloured elliptical eggs are laid singly or in batches of two to four eggs on leaves, shoots, flower buds, calyces, etc. which hatch in 3-5 days. Larva is creamy white, which turns light pink when full grown. Larval duration is 12-22 days. Full fed larva makes an exist hole and pupates on soil. Pupal period is 7-10 days. Adult is white coloured moth having black brown patches on forewings. Newly hatched caterpillars bore into petioles, midribs, tender shoots and fruits. Damaged twigs dry away and the growing point of shoots droop down. later stage the larvae attack flower buds and fruits. Such fruits show exist holes. 158

Brinjal lacewing bug: Adult: bugs are 3 mm long straw colour on the dorsal side and black on the ventral side. Adults hibernate from Nov.-March. There are 8 generations in a year. A female lays 35-44 shining white nipple shaped eggs singly in the leaf tissues. The egg hatch in 3-12 days. Nymphs are pale orcheaus stoutly built with prominent spines. The nymphs go has 5 instars and last for 10-23 days. Both nymphs and adults suck the sap from the leaves causing yellowish spots. The nymphs feed gregariously on the lower surface of the leaf and adults found feeding and moving individually on lower and upper side of the leaf. The black scale-like excreta deposited by them. Brinjal stem borer: Euzopllera perticella Ragonot: Moth is about 30 mm long across the wings having pale yellow abdomen. Head and thorax are grey, the forewings pale straw yellow with hind wings whitish. There are 5 to 6 generations in a year and one generation is completed in 35 to 76 days.A single female lays 104 to 363 cream coloured scale like eggs singly or in batches on the underside of young leaves or in the axel of young branches. Incubation period is 3 -1 0 days. The larva is creamy white with brown head passes through 4 to 5 instars lasts for 2658 days. Brown pupa remains for 6-8 days and the pupation takes place in the silken cocoon within the stem feeding in the galleries. Nature of damage: The young larvae feed for a few minutes on exposed parts of plants before boring into the stem where it feeds on the pith by-making longitudinal tunnel. Damaged plants wither and dry away. Peak period is May-June. Insect pest of cucurbitaceous crops: Red Pumpkin Beetle, Rhaphidopalpa joveicollis (Lucas): Adults are bright yellowish-red beetles, which are good fliers and normally live for about a month. Spherical yellowish pink eggs of this insect are laid in moist soil around the plant, which hatch in 5-8 days. Grubs are dirty white or cream coloured and live for 13-25 days. Pupation in earthen cells deep in soil. Pupal period is 7-17 days. Melon fruit fly: Adult: Flies of this pest are 45mm long, ferruginous brown with hyaline wings. Adult longevity is 2-5 months. White cylindrical, slightly curved eggs are laid below the epidermis of fruits (palp) with the help of stout-hard ovipositor. Egg Period 1-2 days. Larval(maggot) Period 3-9 days Pale-white maggots, which are tapering anteriorly and blunt at posterior end. Brown coloured barrel shaped pupae are formed deep in soil Pupal period is 6-8 days. Newly hatched maggots feed inside the fruit on the pulp. Attacked fruits can be identified by the presence of brown juice oozing out of the puncture made by females for egg laying. Such fruits become distorted, rot and fall prematurely. Pests of Chilli ,Termite,Cut worm,Helicoverpa ,Thrips ,Mealybug ,Yellow mite,Blister beetle Insect Pests of cole crops: Diamondback moth,Tobacco caterpillar,Cut worm, CABBAGE SEMILOOPER CABBAGE HEAD BORER, LEAF WEBBER, APHIDS, CABBAGE BUTTERFLY Insect pests of tomato: fruit borer, whitefly and leaf miner. Pea: BLUE BUTTERFLY

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Components of IPM: Cultural Control, Mechanical Control, Physical Control, Biological Control and Chemical Control IPM: Integration of all control measures stratagies which are economically, ecologically and sociologically acceptable. CULTURAL CONTROL: Use of resistant variety: Role of biotechnology in developing variety throughincorporation of gene. as Bt brinjal, Bt Okra, Bt Tomato, Bt cauliflwer incorporation of early ripening gene as in tomato,Intercropping marigold with tomaoto, Intercropping mustard with cauliflower, Intercropping coriander with brinjal, Cowpea in brinjal, Intercropping onion with cole crops, Trap cropping maize in cucurbits, Border jowar crop in okra. Mechanical Control: Burning of crop residues, As brinjal for shoot and fruit borer, Cucurbitsvine for red pumpkin beetle, Deep burrying of fruit fly damaged fruits, Hand collection of egg masses gregarious larvae of Spodoptera and Pieris from cole crops. Physical Control: Light traps: for Helicoverpa, White grubs,Yellow plastic mulch in brinjal for whitefly, Blue plastic cover: for vegtable against whitefly, thrips and aphid, Yellow sticky traps: for whitefly and aphids, Pheromone traps: for brinjal shoot & fruit borer, Helicoverpa in tomato, DBM in cole crops, White grubs, fruit flies in cucurbits. Biological Control: Trichogramma for H.armigera in Tomato , Encarsia formosa for whitefly in brinjal, tomato and cucurbits, Cotesia plutellae for DBM in cole crops, Predatory mite against mites in veg ,Orius bug pradator against aphids, Chrysoperla in veg soft bodied insects and Coccinellid beetle against aphids. Use of bio insecticides: Bacterial insecticides: Bt, spinosad, spintoram (Helicoverpa in tomato, DBM in cole crops, Leucinodes in brinjal, Earias in okra Viral insecticides: NPV (Helicoverpa) Fungal insecticides: Beauveria, Metarazium (Aphids in coriander and fenugreek) and whitefly) Etomopathogenic nematodes: Stenernema and Rhabdites for mushroom fly, fruit fly and white grub Plant products: Neem oil (Helicoverpa in Tomato),Garlic oil for onion thrips Chemical Control: Seed treatment with neonicotinoids as Imidacloprid, thiamethoxam for jassid in okra (Sharma et. al. Package of practices), Spray of Low dose new molecule: Imidacloprid, thiamethoxam, Emmamectin benzote (Sharma et. al. Package of practices),Growth regulators: as pyriproxifen and novalurom against mites and whiteflies in chilli (Sharma et. al. Package of practices)Mixture of insecticides: Sumiprempt 20EC(Fenpropatherin+pyriproxifen) yellow mite in chilli and red mite in okra 1.

2.

Green leafhopper lays eggs in: a. Leaf veins b. On the leaf c. Lower side of leaf d. None of these Encarsia lutea is a parasitoid of: a. Whitefly b. Aphid c. Grasshopper d. Beetles

3.

4.

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Lace wing bug is a pest of : a. Brinjal b. Potato c. Wheat d. Gram To which crop the Leucinode orbonalis damage? a. Brinjal b. Cotton c. Wheat

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

d. Radish Whitefly is a vector of: a. Gemini virus b. Tungro virus c. Little leaf virus d. None of these Thrips tabaci is a serious pest of: a. Onion b. Potato c. Tomato d. Brinjal Thrips damage the crop by: a. Lacerating and lapping by b. Biting and the leaf the sap c. By piercing and sucking the sap d. None of these. New emerged youngone of whitefly are called: a. Larvae b. Crawlers c. Pupae d. Adults The damaging stage of blister beetle is: a. Adult b. Larvae c. Both of these d. None of these The grubs of blister beetle are: a. Useful b. Harmful c. Both of these d. None of these. The forewings of Earias insulana adult are: a. Green b. White c. Black d. Yellow Tetanychus lerticae is a : a. Mite b. Insect c. Spider d. Bird Red spider mite is a serious pest of: a. Okra b. Mango c. Citrus d. Wheat Yellow mite is a serious pest of: a. Chilli b. Citrus c. Potato d. Gram The damaging stage of red pumpkin beetle is: a. Adult only b. Grub only c. Adult & grub d. None of these.

16.

17.

18.

19.

20.

21.

22.

23.

24.

25.

26.

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The damaging storage of hadda beetle is: a. Egg b. Grub & adult c. Pupa d. None of these Termites feed the chilli: a. Leaves b. Roots c. Flowers d. Fruits Cutworm is an insect which has habit of : a. Nocturnal b. Diurnal c. Both of these d. None of these The red pumpkin beetle lays egg in : a. Leaves b. Fruits c. Soil d. None of these. The colour of the eggs of hadda beetle is: a. Yellow b. Creamy c. White d. Blue Potato tuber moth is a pest of which conditions: a. Field only b. Storage only c. Field & storage d. None of these. The cabbage butterfly young larvae feed: a. Gregariously b. Solitary c. None of these d. Both of these Which of the following is a serious pest of cole crops: a. Diamondback moth b. Hadda beetle c. Lady beetle d. Stink bug The first instar larvae of diamondback moth feed: a. Inside the leaf tissue b. On the fruit c. On the stem d. None of these. The larva of mustard sawfly is a : a. True caterpillar b. Pseid caterpillar c. Grub d. Maggot Melon fruit fly adult lays eggs on: a. Leaf b. In the pulp of fruits c. In the stem

27.

28.

29.

d. None of these The larvae of fruit fly are called: a. Grubs b. Maggots c. Caterpillar d. Semilooper Aphis caraccivora a pest of fenugreek is: a. Black b. Green c. Pale in colour d. None of these. Athalia proxima belongs to family: a. Tenebrionidae

30.

b. Tenethridinidae c. Coccidae d. Apidae Imidacloprid is a : a. Systemic insecticide b. Contact insecticide c. Stomach poison d. None of these.

Answer: 1a, 2a, 3a, 4a, 5a, 6a, 7a, 8b, 9a, 10a, 11a, 12a, 13a, 14a, 15c, 16a, 17b, 18a, 19c, 20a, 21c, 22a, 23a, 24a, 25b, 26b, 27a, 28a, 29a, 30b.

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RECENT APPROACHES FOR STORE GRAINS PEST MANAGEMENT

SS Sharma Department of Entomology CCS HAU Hisar Post harvest Losses in stored grains: The loss at different levels is such as threshing 1.0 %, transportation 0.5 % by rodents 2.5 %, birds 0.5 %, insects 3.0 % and moisture 0.5% and total loss is 8.0 %. Almost all the insect species may destroy 10.0 - 15.0 % of grain and contaminate with undesirable odour. They also help in transportation of fungi. In other report of FAO, the major loss by biotic and abiotic factors is 10%. The major loss is done by two internal feeders i.e. rice weevil and grain borer which are major pests of rice, wheat and millets. This insect feeding on rice grains causes 5-25% weight loss and 20-50 % loss on seed. During storage loss the loss is of two types. a) Quantitative and b) Qualitative Factors responsible for loss in stored grains: Insects, Microorganisms,Temp, moisture and Unscientific storage structures.

Rodents,

Birds,

Mites,

Insects: About thousand species of insect pests found associated with stored products in various parts of the world. The majority of them belong to the orders Coleoptera (60%) and Lepidoptera and 8% related to geographical and climatic conditions cause 2.55 percent out of 9.33% post harvest losses. There are two types of pests which damage the grains in store 1. Primary insect pests: Insects which cause damage to stored grains by directly feeding on the grain at some point in their lifecycle. Primary pest species often develop and reproduce very quickly when the conditions are optimal and the large populations cause considerable damage within few months eg Larger grain borer, Lesser grain borer, Beanbeetle, Peabeetle, Southern cowpeabeetle, Granary weevil, Rice weevil, Maize weevil, Khapra beetle, Rusty grain beetle, Flat grain beetle, Flour mill beetle, Merchant grain beetle, Sawtoothed grain beetle, Angoumois grain moth. 2. Secondary insect pests: Secondary are those insects that require grain out of condition or damaged grain. For example Cigarette beetle, Drugstore beetle, Spider beetles, White marked, spider beetle, Hairy spider beetle, Silken fungus beetles Atomaria, Silken fungus beetles Cryptophagus, Dermestids, Black carpet beetle, Larder beetle, Glabrous cabinet beetle, Mottled dermestid beetle, Ornate carpet beetle, Warehouse beetle, Plaster beetle, Squarenosed fungus beetle, Spotted hairy fungus beetle, Hairy fungus beetle, Sap beetle, Foreign grain beetle, Lesser mealworm, Black fungus beetle, Broadhorned flour beetle, Small eyed flour beetle, Yellow mealworm, Dark mealworm, American black flour beetle, Black flour beetle, Stored-product moths: various species, White shouldered-house moth, Brown house moth, Almond moth, Mediterranean flour moth, Indian meal moth, Meal moth, European grain moth, Clothes moths.

163

The grain mites are listed at the end of the insects because they are not insects but are considered secondary pests of grain. Major insect pests of cereal grains: Larger grain borer, Lesser grain borer, Granary weevil, Rice weevil, Maize weevil, Khapra beetle, Rusty grain beetle, Flat grain beetle, Angoumois grain moth. CARRY OVER OF INSECT INFESTATION IN FOODGRAINS: The following are the important sources of insects infesting stored grains and grain products. Field infestation, Infested godowns , Infested stock, Infested gunny bags/containers, Infested transport and Machinery used in harvesting and post harvesting operations/processing of food grains and grains products. DETECTION OF VISIBLE INFESTATION: Sieving : To detect free living insects in the grain, agitation of Stacks, disturbance of stack or bulk surfaces, by feeling the grains in bulk, by creating the artificial crevices, presence of dead insects, by noting the grain temperature and moisture content, presence of white spots on the grains, presence of white spots of powdered material outside the grain bags and skin cast by the larvae also indicate the insect infestations in grain mass. Or by using the PROBE TRAP or PIT FALL TRAP the infestation can assessed. DETECTION OF HIDDEN INFESTATION: It can be by various methods such as Gentian Violet: Berberine sulphate, FLOATATION OR DENSITY METHOD, GELATINIZATION METHOD, CRACKING, FLOATATION METHOD, SPECTROPHOTOMETRIC ANALYSIS, AURAL METHOD, NINHYDRIN COLOUR REACTION, CARBON DIOXIDE DETERMINATION METHOD and X-RAY RADIOGRAPHIC METHOD IPM IN STORED GRAIN: The management of insects in stored grains/product is in transition from a dependence on regular applications of chemical insecticides to the use of integrated pest management (IPM). IPM involves understanding interactions between stored product environment and insects associated with stored products, and replacing all or most of the chemical applications with costeffective non-chemical alternatives. IPM IN STORAGE CLASSIFIED in to 1) Preventive 2) Curative The saying ―Prevention is better than cure‖ most appropriate for storage insects. But before prevention, sources of infestation in stored grains should be noted as ―Field infestation‖ and ―Hidden infestation‖ by Bruchids and Sitotroga spp., respectively. Cracks and cervices probable site for ―Cross infestation‖. Containers and Bags with Eggs and larval Hidden in the seams and mesh of bags. Trucks, trollies and bullock carts used for transportation of grains. 1. PREVENTIVE: Sanitation/Cleaniness: Cleaniness of stores and receptacle. Removal of old loose and mud plaster. Keep bagged grains/seeds at distance from walls for inspection and fumigation, and avoidance of grains/sees to absorb moisture from moist surfaces. Always keep bags on dunnage. b) Legal method: Imposition of Destructive Insect Pests Act 1914 for prevention of entry of an insect not found in a particular area. 2. Curative: Non-chemical control measure: (1) Ecological control measure (2) Mechanical control measure (3) Cultural (4) Physical control measure (5) Biological (6) Engineering method.

164

Ecological: Temperature, populations.

grain moisture and availability of oxygen regulate to insect

i) Low temperature: Immature stages of almost all insect pests die below 140C. Death occurs rapidly at freezing point (-100C to -200C). Aeration cool ambient air results in low temperature. in general T. castaneum and T. confusum are more cold susceptible whereas T. granarium is most To control stored product pests, insects are exposed to 100C to 200C for some days before being exposed to lethal cold temperature, the low temperature as an alternative to fumigation for disinfecting stored products. To develop quick and safety alternative quarantine treatment for postal item or hand baggage to methyl bromide fumigation, the mortality affects of low temperature exposure to – 180C were investigated on all the developmental stages of 6 stored product insect i.e. Sitophilus granarius, Callosobruchus rhodesianus, Zabrotes subfasciatus, T. granarium, Plodia interpunctella and Ephestia kuehniella. T. casteneum, T. confusum and Oryzaephilus mercator most cold susceptible. T. granarium, S. granarius, E. elutella and P. interpunctella most cold resistant. In T. granarium cold treatment at –180C did not provide rapid kill. low temperature around – 180C was considered as an available quarantine treatment for stored products imported by postal matter. MEANS OF LOW TEMPERATURE : Obtained by aeration with cool ambient air, Bulk grains can be also be cooled by refrigeration. ii) High temperature: High temperature from 50oC to 60oC for 10-20 minutes lethal to all insects. Pupa of Rhizopertha dominica – Heat tolerant, stored seed spices insects die when temperature reaches up to 600C. Temperature 65-680C in the rotating aluminium or stainless steal tubes give 100 % mortality of S. paniceum. 100% mortality of spices insect were exposed to temperature of (500C for 120 m), (600C for 60m), (700C for 45m), (800C for 45m) and (1000C for 15 minutes). The bake-out technique: The use of heat to disinfest storage structures (the bake-out technique) is increasing because it replaces for whole structure fumigation with methyl bromide. In This technique temperature elevated from 500C – 600C, hours to days for Trogoderma larvae to get 99 % mortality. iii) SOLAR BED Means of heating : Hot air, Infra red and Electric and microwave heating. Grain moisture : Grain moisture regulates biological activity of insects in storages. Atmospheric humidity and grain moisture are important factors in their management. Stored grains are dried to safe moisture level before storage, Paddy at 13 % moisture does not allow insects to multiply in storage. Grains stored at around 10 % moisture content escape from the attack of insects (except 'khapra' beetle). MECHANICAL CONTROL MEASURES: Sieving of grains: Broken and cracked grains promote the attack of stored grain pests. Hence, screening/sieving out of such grain reduce the insect infestation. Screening should be done regularly. Immediate destruction of screenings. Bags used for carrying the screenings should not be used again unless disinfected.

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PHYSICAL CONTROL MEASURES: Controlled atmosphere: Controlled atmosphere (CA) disinfestations technology involves the alteration of natural storage gases: Co2, O2 and N2 present in a storage space so as to obtain an artificial atmosphere that prevents multiplication of insects, mould growth and quality deterioration of food grain. (a) High Co2 (b) Low O2 PLANTS AND OTHER NON – TOXIC GRAIN PROCTECTANTS: Environmental friendly biopesticides such as neem Azadirachta indica (eg. leaf, seed, kernel powder, oil and crude extract) possess repellant, antifeedant and feeding deterrent properties against storage insects. Neem seed kernel powder 4%, neem seed oil 1% and mahua oil 1% proved repulsive, potent, oviposition inhibitor in checking damage by T. castaneum upto 8 months. But these can not be applied to spices meant for flavour and condiments. Use of edible oils: Mustard and groundnut oils @ 7.5 ml/kg of stored grains are effective for protection of stored pulse grains against pulse beetle 'Dhora' upto 9 months. Pulse grain protectants namely groundnut oil @ 3.75 ml/kg+ turmeric powder @ 1.75 g/kg, mustard oil @ 3.75 ml + turmeric powder @ 1.75 g/kg, neem oil @ 10 ml/kg. Use of inert material: 7 cm sand and dung cake ash covering on gram proved effective in protecting the treated gram grain from the infestation of pulse beetle, Callosobruchus spp. for a period of 180 days. A six inch layer of road side of pulses for pulse beetles. USE OF IMPROVED STORAGE STRUCTURES: Improved traditional storage structures: Improved structures developed by different agencies are: Pusa Bin, 'Puri', 'Gade', 'Patara', 'Kothi', ‘Pucca Kothi‘. Modern storage structures: Food storage receptacles constructed on scientific basis and techniques can store food grains in safe and sound conditions for long periods. CULTURAL CONTROL: Pulse beetle attacks whole pulses only. Split pulses escape the, attack of Callosobruchus spp. and as such most suitable for storage. CURATIVE: CHEMICAL CONTROL Knock Down Chemical: Pyrethrum spray, lindane smoke generator or fumigant strips useful against flying insects as well as hidden insects. Grain protectants: Recommended mixing of malathion 5D @250g/qtl. For seed grains. Avoid use of EDB in grains meant for seed purpose. Fumigant: Fumigate with aluminium phosphide (Phostoxin/ Celphos) @ 1 tablet (3gm each) for 1 tonne (10 bags) or 7 tablet per 1000 cubic feet or 28 cubic meter space with exposure period of atleast 7 days. EDB – Ethylene dibromide ampoule @ 3ml/qtl. for wheat and pulses but 5ml/qtl. for rice and paddy. EDB also applied @1.7 litres for 1000cubic feet (28.8 cubic meter) space with exposure period of 7 days. Use EDCT – Ethylene dichloride Carbon tetra chloride mixture in the ratio of 3:1 (v/v) for large scale fumigation @ 35 litres/100 cubic meter space in large scale storage with exposure period of 4 days. Use EDCT mixture @ 55 ml/qtl. or one letre for 20 qtls. food grains irrespective of bulk or bag storage. Use Methyl bromide @ 22g/m3. Note: The fumigants should be used only in airtight stores by specially trained personnel. 1.

Tribolium is a pest of: a. Sound grains b. Processed food

2.

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c. Papers d. Clothes Khapra beetle larva is a :

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

a. Germ feeder b. Endosperm feeder c. Frass feeder d. None of these Khapra beetle is a pests of: a. High temp. & low moisture b. Temp. region c. High moisture d. Low temp. e. None of these Rice weevil damage the grain by: a. Making round hole b. Feeders on the germ point c. Feed on the grass d. None of these Lesser grains borer is a pest of: a. Cereal grains b. Pulses c. Oilseed d. Processed food. Which stage of khapra is harmful: a. Adult b. Grub c. Both adult & grub d. None of these. Sursari adult live for : a. 1-2 days b. 10-15 days c. About 6 months d. More than one year. Khapra beetle adult is a: a. Short lived b. Long lived c. Very very long live d. None of these. The grubs of khapra beetle can live without food: a. Upto 6 yrs. b. Cannot leave without food c. Both of these d. None of these Khapra beetle is a serious pest of: a. Legumes grains b. Wheat c. Beans d. Sarson Callosobruchus chinensis is a serious pest of: a. Wheat b. Gram c. Oilseeds d. Bajra. Which of the following is a pest of moong grains: a. Bruchus anals b. Khapra c. Sursari

13.

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d. Rice weevil The bruchids deposit eggs: a. On the walls of storage b. On gunny bags c. In the grass d. On the surface of grains The round holes present on gram grains are: a. Entry holes b. Exist holes c. Feeding holes d. None of these Rice weevil belongs to family: a. Cuculionide b. Aphidae c. Fulgoridae d. Aphelinidae Cigarette beetle is a pests of : a. Cereal grains b. Pulse grains c. Spices d. Oilseeds Ephestia cautella is a pests of: a. Dry fruits b. Cereal grains c. Pulses d. Oilseeds. Infestation of bruchids takes place from: a. Field only b. Store only c. Field & store d. None of these. Which stage of gram dhora is harmful: a. Adult b. Grub c. Both d. Egg Khapra beetle is an: a. External feeder b. Internal feeder c. Frass feeder d. All of these During quarantine which is the most popular method detection of infestation: a. Xray b. Siering c. Chemical method d. Windowing Sursari beetle belongs to family: a. Anobiidae b. Tenebrionidae c. Aphidae d. Coccinellidae. Which stage of grain moth is harmful? a. Adult b. Larvae c. Egg

24.

25.

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27.

d. Pupa Which is preventive method for stored grains insect pests: a. Cleanliness b. Spray of insecticides c. Use of fumigants after infestation d. None of these Which of the following is a fumigants: a. Malathion b. Monocrotophos c. Fenvalerate d. Aluminium phosphide

a. b. c. d. 28.

29.

Aluminium phosphide kills the insects by destroying the: a. Respiratory enzyme b. Digestive enzyme c. JH d. None of these. Stagobium panicium is a:

30.

Drug beetle Gram beetle Lady beetle Hadda beetle

Which stage of cigarette beetle is harmful: a. Larvae b. Grub c. Both d. None of these Rhizopertha dominica is a primariy pest of: a. Oil seed b. Pulses c. Wheat d. Mungbean Sitogroga cerealella is a pest of : a. Cereal grains b. Spices c. Pulses gram d. Oil seeds

Answer :1b, 2a, 3a, 4a, 5a, 6b, 7c, 8a, 9a, 10b, 11b, 12a, 13d, 14b, 15a, 16c, 17a, 18c, 19b, 20a, 21a, 22b, 23b, 24a, 25d, 26a, 27a, 28b, 29c, 30a

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MAJOR INSECT PESTS OF FRUIT CROPS AND THEIR MANAGEMENT HD Kaushik Department of Entomology CCS HAU Hisar India is bestowed with varied climatic conditions and more than two dozen fruit and plantation crops are grown. It is the second largest producer of fruits in the world, just behind China. The area under fruit cultivation in 2011-12 was 6.704 million hectares with a total production of 76.4 million tonnes (Source: Ministry of Agriculture, GOI, and website: www.nhb.gov.in).The major fruits grown in India are mango, banana, citrus, guava, grape, pineapple, pomegranate, and apple. Although fruits are grown throughout the country, the major fruit and plantation growing states are Maharashtra, Tamil Nadu, Karnataka, Andhra Pradesh, Bihar, Uttar Pradesh, Gujarat, Kerala and Goa. India ranks first among banana producing countries in the world with a production of 29.7 million tonnes from an area of 830 thousand ha. In the year 2010-11, Tamil Nadu lead in area (125.4 thousand ha), production (8253.40 thousand tonnes) and productivity (65.8 mt/ha). The other major banana growing states are Maharashtra, Karnataka, Gujarat, AndhraPradesh, Bihar, Uttar Pradsh, Madhya Pradesh and Assam (www.apeda.gov.in). Mango, referred to as the ‗King of fruits‘ is the most important commercially grown fruit in India and ranks first among mango producing countries accounting for 50 percent of the world‘s production. India has the richest collection of mango cultivars. Major mango producing states are Uttar Pradesh, Bihar, Andhra Pradesh, Odisha, West Bengal, Maharashtra, Gujarat, Karnataka, Kerala and Tamil Nadu. Uttar Pradesh ranks first in production with 3,841.00 thousand tonnes. Moreover, the productivity of fruit and plantation stated for the last many years remained static. This has been attributed to diseases and insect pests that were of little economic importance in the past, but have now emerged as new threats to the growers in some localities. Apart from bacterial blight, wilt, thrips and fruit borer along with new pests like some fungal fruit rots and spots, and fruit sucking moth required immediate attention. Around 800 species of insects have been found damaging fruit trees in India. To check the damage, orchardist are using insecticides injudiciously which are resulting in environmental pollution and health hazard to human beings. So, to harvest the healthy crop and to have the eco-friendly environment, integrated insect-pest management practices must be advocated to the orchardist. Awareness among growers to identify and manage insect pests of fruit crops is essential for higher productivity as well as for quality produce. This requires long term strategies to manage risks such as pests and diseases following the principles of integrated pest management. Farmers tend to overuse pesticides which are detrimental to human health as well as to the environment. They have to be advised to apply need based pesticides.

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Fruit Crops (A). Mango (Mangifera indica) 1. Mango hoppers (Cicadellidae: Homoptera) Three species of hoppers are found to feed on the inflorescence of mango Amritodus atkinsoni (Lethierry), Idioscopus clypealis (Lethierry) and I. niveosparsus (Lethierry). Distribution: In India, these hoppers are widely distributed in all the mango growing regions. A. atkinsoni is more common in North India. I. clypealis is found all over India, more predominant in South Gujarat, Maharashtra and Karnataka. I. niveosparsus is recorded from peninsular India. Nature of damage: The hoppers are found in abundance during November – February synchronizing with the flowering of mango trees. During the remaining part of the year they occur in small numbers inside barks or on leaves of mango. Both the nymphs and adults suck the sap from the inflorescence in large numbers causing withering and shedding of flower buds and flowers which result in heavy loss ranging from 25 - 60 per cent due to poor fruit setting. The honey dew excreted by them affords conditions for development of sooty mould. Egg laying also inflicts injury to the inflorescence. Life history: I. niveosparsus (L.) is slightly smaller with three spots on the scutellum and prominent white band across its light brown wings. I. clypealis (L.) is the smallest with two spots on the scutellum and dark spots on the vertex and is light brown in colour. A. atkinsoni (L.) is the largest and light brown having two spots on the scutellum. The female hopper inserts the eggs into flower buds and the inflorescence stalk. The nymphs hatch out in 4 to 7 days. Freshly hatched nymphs are wedge shaped and whitish in colour with two small red eyes. Gradually with each moulting, the colour changes to yellow, yellowish green, green and ultimately greenish brown. The period from egg to adult takes about 12 - 17 days and during a flowering season two or more broods of the pest may occur. Management strategies: (i) Three applications of carbaryl 0.1 % or phosalone 0.05 % at fortnightly interval, or, two sprays of phosphomidon or monocrotophos @ 0.03% at 13 to 18 days interval at flowering and 2 – 3 sprays in June – July. (ii) Keeping the orchards clean, avoiding over crowding of trees and water logging keeps the pest at bay. 2. Flower webber Eublemma versicolor Wlk. (Noctuidae: Lepidoptera) Distribution: Found distributed in all mango growing areas. Nature of damage: The flowers in the inflorescence are webbed together by the larva and inside this silken gallery it remains and feeds causing considerable damage. The larvae also bore into the inflorescence stalk. Life history: The female moth has purplish grey wings and the male has purplish pink or light orange wings with an apical patch. The female lays 8 - 10 reddish hemispherical eggs on sepals and the incubation period is 3 - 4 days. The full grown larva is smooth, greenish yellow with light brown head and prothoracic shield and measures about 20 mm long. The larval period is 18 – 20 days. It pupates inside the inflorescence and emerges as adult in 8 - 9 days. The life-cycle 170

occupies 29 - 33 days. In Kerala Eublemma angulifera M. has been noticed to attack the inflorescence. Management strategies: Two to three application of phosalone 0.05% at fortnightly interval at flowering. 3. Gall midges infesting mango inflorescence Distribution: Three species of gall midges viz., Procystiphora mangiferae (Felt), Dasineura amaramanjarae Grover and Erosomyia indica Gr. & Pr. are found throughout India. Nature of damage: Due to the attack of unopened flower buds, they fail to open and drop down. When the inflorescence stalk is attacked, the inflorescence becomes stunted and malformed. Life history: (i) Procystiphora mangiferae (Felt): The light orange coloured fly lays the eggs inside immature blossoms. The maggots that hatch out from the eggs feed on stalks of stamens, anthers, ovary, etc. Only one maggot is found in each bud and it pupates inside the bud itself. The life-cycle from egg to adult occupies 12-14 days). (ii). Dasineura amaramanjarae Grover: The adult flies insert the eggs into unopened flower buds. The maggots feed inside the buds and they fail to open and drop down. The maggots hibernate in the soil and thus carry-over of the pest to the next year is accomplished. When favourable conditions set in they pupate and emerge as adults (iii). Erosomyia indica Gr. & Pr.: The maggots attack the inflorescence stalk, flower buds and small developing fruits. The adult fly is yellowish and lays the eggs on the infloresence peduncle or at the base of‘ developing fruit. The maggots are yellowish and when full grown pupate in the soil. Management strategies: (i) Stem injection by making 5 – 10 cm deep holes in the main branches with dimethoate or monocrotophos @ 0.5 ml a.i./cm circumference gave effective control of the pest. (ii) Single spray of 2, 4-D @150 mg/l in October resulted in opening of galls causing 90% autocidal mortality of the nymphs. 4. Fruit fly Bactrocera dorsalis Hendel (Tephritidae: Diptera) Distribution: It is widely distributed in the Orient region from Australia and Hawaii to Pakistan, hence it is also called Oriental fruit fly. The pest is active throughout the year in South India whereas in northern parts the pest hibernates during winter (November to March) in pupal stage. The flies appear late in spring on such of the fruits that are about to ripe and the population increases rapidly during summer. Nature of damage: The female flies lay eggs just below the fruit epidermis (1 - 4 mm deep). On hatching the maggots feed on pulp of those fruits. As a result a brown patch appears around the place of oviposition and the infested fruits start rotting. These affected fruits drop down prematurely and the maggots come out from these fallen fruits to pupate in the soil. Semi ripe fruits are attacked usually by April-May. Sometimes it becomes serious.

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Life history: The adult fly is light brown with transparent wings. Adult flies are very conspicuous. These are about 7 mm long, with hyaline wings (expanse : 13 - 15 mm), thorax ferrugineous without yellow middle stripe, legs yellow, abdomen conical in shape and dark brown in colour. Preoviposition period is 2 - 5 days. A single female can lay 150 - 200 eggs (average 50) in about a month. The eggs are laid in clusters of 2 - 15 eggs and these hatches in 2 - 3 days during March and 1 - 1½ days during April. Maggot duration is 6 days in summer and extends up to 19 days with the fall in temperature. Pupation usually takes place 80 - 160 mm below the soil surface and pupal period ranges from 6 days (summer) - 44 days (winter). Management strategies: (i) The best way to avoid infestation of fruit flies is to harvest the fruits before ripening. (ii) To check the carry over of the pest, collect and destroy all fallen and attacked fruits. (iii) Plough around the trees during winter to expose and kill the pupae. (iv) The adult flies may be trapped and killed by poison-baiting or bait-spray (20 gm Malathion, 50% wettable powder in 2 liters of water for baiting and 20 litres of water for spraying. (v) Spraying with 0.3% oxydemeton methyl or 0.03% phosphamidon or 0.06% dimethoate or 0.2% carbaryl. 5. Mango nut weevil or stone weevil Sternochetus mangiferae (Fb.) (Curculionidae: Coleoptera) Distribution: It is widely distributed in the tropics. The pest is more common in South India where late varieties suffer the most. Nature of damage: Eggs are laid singly on the epicarp of partially developed fruits or under the rind of ripening fruits. The grubs as soon as they hatch out from the eggs tunnel in a zigzag manner through the pulp, endocarp and the seed coat and finally reach the cotyledons. As the fruit develops the tunnels get closed up. The grubs feed on the cotyledons and destroy them. The adults which emerge from the pupae also feed on the developing seed and this may hasten the maturity of infested fruits. The adults hibernate in between the crevices on the tree trunks. The weevil attacks only mango. Life history: The dark brownish stout weevil measures about 6 mm long. The female scoop out the surface of the developing fruit (till it is half ripe) and deposits the eggs singly. On a fruit 12 36 eggs may be deposited. However, finally only a maximum of about 7 weevils can be noticed in a highly susceptible variety. The fluid that oozes from the fruit covers the egg. The incubation period is 7 days. The grub is apodous, fleshy, light yellow with a dark head and pupates inside the nut itself. It emerges as adult in 7 days. The total life cycle from egg to adult occupies 40 - 50 days. The weevils hibernate from July – August till next fruiting season. There is only one generation in a year. Management strategies: (i) The damage due to nut weevil can be minimized appreciably by spraying deltamethrin 0.025 % thrice at 15 days interval commencing 45 days after fruit set. (ii). Carbaryl 0.2% spray when the fruits are lime sized followed by another spray after 15 days. (iii). Destruction of affected fruits and digging of soil to expose hibernating weevils. 172

6. Mango stem borer Batocera rufomaculata DeG. (Cerambycidae: Coleoptera) Distribution: Widely distributed all over India and Bangladesh attacking apart from mango other trees such as fig, rubber, jackfruit, eucalyptus, mulberry etc. The mango varieties Amlet and Mulgoa are highly susceptible to the attack of this insect. Nature of damage: Eggs are laid singly either in the slits of tree trunks or in the cavities in the main branches and stem which are covered with a viscous fluid. The grubs feed by tunneling through the bark of branches and cause wilting. Though it is an occasional pest of importance, in case of severe attack the trees succumb. Normally, the attack goes unnoticed till the branch start drying up. Sometimes sap and frass may be seen exuding from the bore holes. Life history: The adult beetle has two pink dots and lateral spines on thorax and measures about 50 mm long. The eggs laid singly on the bark or in crevices on tree trunk or branches hatch in about 1 - 2 weeks. The grub feeds for 3 - 6 months and pupates inside the tunnel itself. The adult emerges in about 4 - 9 months. Management strategies: (i) The attacked portions should be removed and destroyed. (ii) The grubs can be killed by pouring chloroform, petrol or carbondisulphide into the bore hole or placing some crystals of paradichlorobenzene and then closing the hole with mud. 7. Red tree ant Oecophylla smaragdina Fb. (Formicidae: Hymenoptera) Distribution: It has been reported from the entire Oriental region extending from Australia to Africa. Nature of damage: The ants web and stitch together a few leaves usually at the top of the branches and build their nests on citrus, jack-fruit, jamun, litchi, mango, sapota etc. The ants do not cause any direct injury or loss to the tree. Indirectly, the damage is caused by protecting aphids and scale insects from being preyed upon by their parasitoids and predators and also carries the nymphs of aphids, mealy bugs and scale insects from tree to tree thus spreading the infection of these noxious pests. Besides, being very ferocious, they also prove to be a nuisance to the persons who climb the trees and other workers around, who often get badly bitten by these ants. Life history: Eggs are oval in shape and whitish in colour. Larvae are also whitish, 1.2 - 1.4 mm long when freshly formed while full grown ones are 9 - 11 mm long. Pupae are also pure white in colour. Adults are light orange red in colour; the workers are 14 - 18 mm long, wingless and infertile. Sexually functional males and females are winged and usually mate outside the nests in the course of their nuptial flights. The fertilized females, also known as Queens, shed their wings at the time of nest formation. Egg, larval and pupal periods occupy 4 - 8, 10 - 17 and 5 - 7 days respectively. Management strategies: (i) Spray application of cypermethrin 0.025 % controls it. (ii) Removal and destruction of nests mechanically. 173

8. Mango mealy-bug, Drosicha mangiferae (Green) (Coccidae: Homoptera) Distribution: In India, it is widely distributed in the Indo-Gangetic plain and has a very wide range of host plants. This pest has been reported from many places in India, Bangladesh, Pakistan and China. It is reported to attack a number of fruit crops such as apple, apricot, ber, cherry, citrus, falsa, fig, grapevine, guava, gular, jack-fruit, jamun, litchi, mulberry, papaya, peach, plum and pomegranate. Nature of damage : These are large, fleshy, flat-bodied creatures measuring about 1.5 cm in length and a little less than a centimeter in width, covered with ashy-white mealy powder and crawling up or down the tree-trunks or on the ground round the tree-base or even invading the houses if the mango trees are near about. These mango mealy-bugs are also referred to as the giant mealy-bugs. They suck the plant-sap and although their name seems to suggest that they are specific pests of mango only, their list of food plants includes at least 62 species of trees, shrubs and herbs. When they are in large number they devitalize the plant and they produce honeydew which encourages growth of sooty mould, giving a very unhealthy look to the plant as a whole. At times, they are found clustering in masses on young shoots, like fungus outgrowths. Life history: There is a well-established sexual dimorphism in the adult stage which is generally found during the midsummer period, i.e. from April to June. Adult females are wingless and large-bodied. The male is a winged creature with only one pair of wings and a very delicate reddish body which flies actively and fertilizes the females. The adult gravid females after fertilization crawl down along the tree-trunk to the ground where they lay eggs at depths of about 5 - 15 cm and in clusters of 300 - 400 eggs each. The oviposition is generally confined to an area near and around the base of the tree. These activities of migration from the tree downwards to the ground and oviposition in the soil are generally confined to the months of April, May and June. The males die soon after mating and the females soon after oviposition. The eggs laid in the soil take quite a few months before they hatch and is influenced by the temperature and moisture conditions of the soil. Hatching can be as early as November of the same year or as late as March of the succeeding year. The young nymphs soon after hatching crawl about in search of some suitable food-plant on which, if found, they spend some time. Thereafter, they begin their ascent along the tree-trunks and this upward migration lasts for several weeks. On reaching the fresh growths, the nymphs congregate there and begin to suck the plant-sap. They moult thrice during their nymphal period which lasts about three months or more, depending on the environmental temperature. Thereafter, the nymphs developing into males undergo some sort of pupation and transform themselves into winged adults and the female-producing nymphs do not undergo any appreciable change except in size. Thus, there is only one generation during the year. Unlike many other coccids, the nymphs of this pest do not remain stationary although they are sluggish. Management strategies: (i) Raking of the soil around the base of the tree which has been infested, so that the egg-masses get exposed to the sun and heat and get killed. Also, the application of chlorpyriphos 0.05% in the same area when hatching begins or is expected, so that the just-hatched nymphs may be poisoned. (ii) Application of a sticky band round the tree-trunk so as to check the nymphs from crawling up the trees. 174

(iii) If nymphs are observed on trees, spray 0.05% monocrotophos or phosalone. (B). Sapota (Manilkara achras) : 1. Leaf webber Nephopteryx eugraphella Rag. (Phycitidae: Lepidoptera) Distribution: A common pest of sapota throughout India. Nature of damage: The caterpillar webs and feeds on the leaves. It also feeds on flower buds and fruits and 3 - 4 larvae may occur together occasionally. Leaves of Mimusops elengi and cured tobacco are also infested by the larvae. Life history: The grayish moth lays pale yellow eggs on leaves singly or in groups of two or three. The pinkish larva measuring 25 mm long has close-set of longitudinal lines on the dorsal surface. Pupation takes place in the leaf web itself. The total life-cycle occupies 32 - 45 days, the egg, larval and pupal periods respectively being 3 -5, 17 - 32 and 7 - 11 days. Management strategies: (i) The damaged leaf webs with larvae should be collected and destroyed. (ii) Spray application of cypermethrin 0.025 % affords protection. 2. Hairy caterpillar Metanastria hyrtaca C. (Lasiocampidae: Lepidoptera) Distribution: This pest is found on a number of tree crops including sapota in different parts of India. Nature of damage: The caterpillars feed on leaves voraciously and defoliate the trees. Life history: The female moth has grayish brown wings and is stout. The male is smaller and has a white spot in the centre of a black patch on forewing. The antenna is pectinate. The moth oviposits on leaves or twigs in rows or groups and lays about 140 eggs. The incubation period is 9 - 12 days. The long stout grayish hairy caterpillar measuring about 65 mm long has black head and median dorsal brownish band extending to second abdominal segment. The larval stage occupies 45 - 60 days. Pupation takes place on tree trunks in a cocoon of silk and body hairs. Pupal stage occupies 7 - 10 days. Management strategies: (i) Spraying of cypermethrin 0.025%. (ii) Burning the groups of larvae found on tree trunks with torches. (C). Guava (Psidium guajava) 1. Tea Mosquito bug : Helopeltis antonii S. (Miridae : Hemiptera) Distribution: It is found attacking tea, neem, cashewnut and guava in different parts of India. It is serious on tea in Kerala.

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Nature of damage: The nymphs and adults of the tea-mosquito bug Helopeltis antonii (Miridae) cause corky scabs formation on fruits. The blisters are formed due to the toxic substance injected by the bugs. Due to the attack the fruits become unsuitable for marketing. Life history: It is a slender insect 6 - 8 mm in length with a yellowish brown head and abdomen, a dark red thorax and long dark appendages. The adult lays elongate and sausage shaped eggs that possess two filamentous long processes which remain jutting out from the tender plant tissue in which the eggs are bedded by the female. Incubation period varies between 5 - 27 days. The newly hatched nymphs resemble spider in general appearance with elongate appendages. They undergo five moults and complete one generation in two weeks in June and eight weeks or more in cold weather. Management strategies: Periodical spray application of Malathion 0.1 per cent has been reported to minimize damage 2. Guava Fruit Fly :- Bactrocera spp. (Tephritidae: Diptera) Life history and Nature of damage: Shiny white eggs are laid in soft skin of ripening fruits. On hatching grubs of pale white colour bore into the fruits and feed on the soft pulp. Unripe fruits are seldom attacked as these fly are unable to puncture the hard skin. The infested fruits get malformed and ultimately fall down. Pupation takes place in soil. Adult stage is harmless. Management: Remove the infested and fallen fruits as they serve the source of reinfestation. Do not leave the over ripened fruits on trees as they attract the flies. Rack the soil during summer to' kill the pupae. If the infestation is still present then spray 500 ml malathion 50 EC + 5Kg gur in 500 lit. water per acre. (D). Banana (Musa spp.) 1. Rhizome weevil Cosmopolites sordidus G. (Curculionidae: Coleoptera) Distribution: One of the most serious insect pests of banana all over the world, found distributed in South Asia, Africa, many pacific islands, Australia, Northern South America, Central America, West Indies and some parts of North America. In India reported as serious pest in Kerala, Tamil Nadu, Andhra Pradesh and other banana growing areas. Nature of damage: The dark weevil oviposits in the root stock or leaf sheath just above the ground level. The grubs and adults bore into the rhizome and cause stunting of rhizome development. If the infestation occurs on a mature rhizome, damage symptoms appear through the reduction in the leaf number, bunch size and the fruit number. Most damage is done by extensive tunneling of the larvae in the corn, thus weakening the plant and causing blow-down by even slight winds. Life history: Adults lay eggs in between leaf sheaths and stems as well as around the corn, often in an enlarged cell-like compartment in the tissue. Eggs are laid singly and the newly hatched larvae bore into the corm. The egg, larval and pupal stages are completed in 5 - 7, 15 - 20 and 6 8 days, respectively. Adults can live over two years without food. 176

Management strategies: (i) Adopt strict field sanitation by removing infected plants and destroying them. (ii) Deep ploughing before planting to expose the weevils to sun and predators. (iii) Use of healthy planting material and removal of outer layer of rhizome and sun dry for 3 - 4 days before planting after smearing with slurry of cowdung and ash. (iv) Setting traps in the field using length-wise split pseudostem of 50cm length. Adults attracted to it during nights may be collected and destroyed. (v) Drenching with chlorpyriphos 0.1% emulsion in the soil before planting may afford some relief. 2. Banana Stem Weevil Odoiporus longicollis Oliver (Curculionidae: Coleoptera) Distribution : It is distributed in Asia, Bhutan, China, Guizhau, Hong Kong, Indonesia, Java, Sulawesi, Sumatra, Japan, Laos, Malaysia, Sabah, Myanmar (Burma), Nepal, Nicobar Islands, Phillippines, Sri Lanka, Taiwan and Vietnam. In India, it is distributed in Assam, Bihar, Haryana, Kerala, Manipur, Sikkim, Uttar Pradesh, West Bengal and in Andaman Islands. Nature of damage: Infestation of the weevil starts in 5 month old plants. Early symptoms of the infestation are the presence of small pinhead sized holes on the stem, fibrous extrusions from bases of leaf petiole and exudation of a gummy substance from the holes on the pseudostem. In advanced stages of infestation, the stem when split open will show extensive tunneling both in the leaf sheath and in the true stem. Rotting occurs and foul odour is emitted due to secondary infection of pathogens. When the true stem and peduncle are tunnelled after flowering, the fruits do not develop properly, become dehydrated with premature ripening of the bunch. Weakening of the stem by larval tunneling often result in breakage by wind. The estimated yield loss due to this pest is between 10 – 90% depending on the growth stage in which the infestation occurs and it is the highest in 5 months old crop. Life history: The adult weevils are black-coloured and measures 23 - 39 mm. Red coloured morphs are also encountered. All life stages of the weevil are present throughout the year. Adults are strong fliers and this way they spread quickly from field to field. The pre-oviposition period is 15 - 30 days. The adults mate throughout the day and night and after a single mating lay an average number of one egg per day for 9 days. Gravid females lay yellowish white, 3.14 x 1.1 mm sized elliptical eggs through ovipositional slits cut by the rostrum on the outer epidermal layer of the leaf sheath of the pseudostem. The incubation period ranges between 3 - 8 days. The larvae are fleshy, yellowish white and apodous and they pass through 5 instars. Pupation takes place in a fibrous cocoon and the pupate are exarate. The total life cycle from egg to adult stage is competed in 44 days. Management strategies: (i) Field sanitation by removing and destroying the affected plants alongwith rhizome and also the destruction of pseudostem and rhizome of harvested plants is the most important method. th

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(ii) Application of carbofuran 3g @ 30g/plant at planting and @ 15g/plant at 60 and 90 day after planting.

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(iii)Spray application of quinalphos 0.05% or chlorpyriphos 0.03% or carbaryl 0.2% at planting. In case of severe infestation spraying may be repeated after 3 weeks. 3. Banana aphid – Pentalonia nigronervosa (Coquerel) (Aphididae : Homoptera) Distribution: It is present every where in the world where banana is grown. It occurs on a number of food and ornamental plants including floral red and pink ginger, cardamom, Heliconia, Ginger etc. Nature of damage: Nymphs and adults suck the sap causing deformation of plants. The leaves become curled and shriveled and in case of severe infestation young plants are killed. Feeding also results in honey dew secretion on which the sooty mould grows resulting in decrease of photosynthetic activity and vigour of the plant. It is a vector of the ―bunchy top disease‖ in banana and ―Katte disease‖ in cardamom. Life history: They reproduce parthenogenetically giving rise to nymphs which complete their life cycle in 9 - 16 days. The first, second, third and fourth nymphal stages are completed in 2 4, 3 - 4, 2 - 4 and 2 - 4 days, respectively. Management strategies: (i) Application of 25g of phorate 10G or 20g of carbofuran 3G /plant 20 days after planting around the rhizome in the soil. (ii) Application of 12.5g phorate 10G or 10g of carbofuran 3G /plant in the leaf axils or 25g phorate 10G or 20g carbofuran 3G /plant in the soil 75 days after planting which may be repeated 165 days after planting. (E). Pomegranate (Punica granatum) : 1. Anar butterfly Deudorix (=Virachola) isocrates F. ) (Lycaenidae : Lepidoptera) Distribution: It is a polyphagous pest having a very wide range of host plants, including, aonla, apple, ber, citrus, guava, litchi, loquat, mulberry, peach, pear, plum, pomegranate, sapota and tamarind. It is widely distributed all over India and is found wherever pomegranates are grown. Pomegranate fruits are also damaged by pomegranate borer, Deudorix epijarbas (Moore). Nature of damage: The female lays eggs singly on calyx of flowers or small fruits. On hatching, the caterpillars bore inside the developing fruits and are usually found feeding on pulp and seeds just below the rind. As many as eight caterpillars may be found in a single fruit. Subsequently, the infested fruits are also attacked by bacteria and fungi causing the fruits to rot. The conspicuous symptoms of damage are offensive smell and excreta of the caterpillars coming out of entry holes, the excreta are found stuck around the holes. Sometimes the holes may also be seen plugged with the anal end of a caterpillar. The affected fruits ultimately fall down and are of no use. Life history: The bluish brown butterfly has an orange spot on each of the fore wings and black spots on the hind wings. The eggs are laid singly on flowers and tender fruits. Eggs are shiny white in colour and oval in shape. The egg hatches out within 7 - 10 days. The caterpillar measures 16 – 20 mm long, dirty brown and has short hairs on its body. Larval period is 14 – 45 days. Just before pupation, the caterpillars come out of the fruits and tie the stalk of fruit with 178

main branch of the tree with fine silken strands to ensure that the fruit does not fall down, then reenter the fruit and pupate therein or on fruit stalk. Pupal period varies from a week to more than a month. The total life-cycle may take 1 - 2 months depending upon the weather. It has four overlapping generations in a year. Management strategies: (i) The fruits if screened with polythene or paper bags may escape infestation. (ii) Five spray application of fenvalerate 0.01 %, or carbaryl 0.2 % or triazophos 0.05% or 0.03% phophamidon at intervals of three weeks commencing at initiation of fruit setting. (iii) Removal and destruction all the affected fruits. 2. Bark Eating Caterpillar: lndarbela quadrinotata (Metarbelidae: Lepidoptera) Life history and Nature of damage: It is a polyphagous pest found damaging aonla, ber jamun, mulberry, pomegranate and a number of forest and ornamental trees. A single female lays about 2000 eggs on the bark of host tree during April to June.Larvae are full grown by December and continue to feed slowly till April when pupation takes place. Pupal period varies between 21 to 31 days. Moth emergence continues till June and there are recognizable hardly for 3 days. There is only one generation in a year. Caterpillars which are dirty brown nibble the tree trunk and after 2- 3 days bore into the same and feed with in resulting into the interruption of translocation of cell sap. Due to this growth fruiting capacity of tree is adversely affected. Damage by this best can easily be recognized as silken web consisting of excreta and chewed particles are found hanging. Older trees are more prone to attack. Management: Keep the orchard clean and avoid over crowding of trees. Kill the larvae inserting iron spike into the holes. Remove the webbing and injecting to each hole 5 ml emulsion prepared by diluting 2 ml dichlorous 76 EC or 5 ml methyl parathion 50 EC or 30 ml endosulfan 35 EC or 40 g carbaryl 50 W.P. in 10 lit. water during September-October and again in February- March. Treated holes should be plugged with mud. (F) Citrus (Citrus spp.) 1. Lemon butter fly : Papilio demoleus (Papilionidae: Lepidoptera) Life history and Nature of damage: These are found throughout the year, though rare during winter. Their attack is more pronounced in nurseries and young plantation where the seedlings and trees may be completely defoliated. Eggs are pale green while young larvae are tuberculate blackish brown with milky white markings where as full grown caterpillars are green in colour. There are four to five overlapping generations in a year in North India. Management: Hand picking of larvae and their destruction. Conserve the parasitoides: Telonemus sp., Trichogramma .sp. etc. Spray ecofriendly insecticide Bacillus thuringiensis, 750 ml enclosulfan 35 Ec or 500 ml monocrotophos 36 WSC in 500 lit. water per acre if needed.

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2. Citrus whitefly-: Dialeurodes citri (Aleyrodidae: Hemiptera) Life history and Nature of damage: Nymphs and adults reduce the plant vigour by sucking large quantities of cell sap. Severely infested leaves turn pale brown, get badly curled. Copius quantity of honey dew also produced on which sooty mould develops, covering the foliage which interferes with the photosynthetic activity of plant. Affected trees produce less blossom and fruits are insipid. Nymphs are pale yellow and adults are pale yellow with red eyes. Pest is active from March to August. Management: Avoid close planting and water logging. Clip-off and destroy localized attack. Conserve the natural enemies like Chrysopa sp. Use the insecticides suggested as under citrus butterfly. 3. Citrus psylla: Diaphorina Citri (Psyllidae: Hemiptera) Life history and Nature of damage: It is a serious pest in Punjab, Delhi and Haryana. Orange coloured eggs are laid in folds of half opened leaves or flower buds or petioles of leaves. On hatching orange coloured nymphs cause the damage to leaves, terminal shoots and buds by sucking the cell sap. Bugs also excrete the honey dew resulting in the superficial black coating on the affected parts Pest remains active during spring and again August to November. Adults are brownish bugs found sitting on the ventral surface of leaves. Management: Conserve the natural enemies like Coccinella sp. and Chilocorus nigritus . Modify the canopy for light interception. Do not allow the intermittent flush. Apply insecticides oxydemeton methyl 25EC 750 ml or dimethoate 30 EC 600ml or phosphomidon 85 WSC 180 ml or monocrotophos 36 WSC 500 ml in 500 lit. water per acre. (G) Ber (Zizyphus spp) 1. Ber fruit fly : Carpomyia vesuviana (Tephritidae: Diptera) Life history and Nature of damage: It is a specific pest of ber (Zizyphus spp) both wild and cultivated. It causes up to 77 percent damage to fruits (Nair, 1975). Unlike other fruit flies (Bactrocera spp) this fly becomes active in autumn and the activity continues through out winter and spring. Maximum damage is caused during February March. Females start laying eggs inside the epidermis in November when the fruits are of pea size. On hatching, maggots feed on fleshy and juicy pulp and fruits become deformed and unfit for human consumption and lose the market value. Pupation takes place in soil (2-5 cm layer of soil) Early and late ripening varieties those possessing thin skin and sweeter flesh are preferred . Management: To suppress the population of fly, remove and destroy all infested fruits, remove all the wild bushes from the vicinity of grafted ber orchard. Rake the soil around the trees frequently specially during summer to kill the pupae. Use the insecticides judiciously to protect some larval/pupal parasitoids like Biosteres sp., Bracon fletcheri, Opius carpomyial etc. When majority of fruits have attained pea size, spray the trees with 600 ml oxy-demeton methyl 25 EC or 500 ml dimethoate 30 EC in 500 lit. water per acre. Repeat the- spray after 30-45 days if necessary. When fruits are ripe, spray (if needed) 500 ml malathion 50 EC +5 Kg sugar/gar in 500 lit. water per acre.

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2. Plum hairy caterpiller : Euproctis fraterna (Lymantridae: Lepidoptera) Life history and Nature of damage: It is a polyphagous pest of fruit trees and widely distributed in arid ecosystem. Newly hatched larvae feed gregariously on lower surface of leaves feeding on chlorophyll while later stages are solitary and feed voraciously when caterpillars scrap the skin of fruits. Larval stage lasts for 25-56 days. The .pest remains active from July to April having 6 or more generations. Management: Pluck the leaves with egg mass and gregariously feeding young larvae to destroy them mechanically. This is the most effective and economical method. In the late stage spray the trees with 500 ml monocrotophos 36 WSC or 1 lit. endosulfon 35 EC or quinalphos 25 EC or 1 kg carbaryl 50 WP in 500 lit. water per acre. 3. Cockchafer beetles : Holotrichia spp., Anomala Spp. Adoretus Spp., Schizonycha spp. (Scaraebaeidae: Coleoptera) Life history and Nature of damage: It is a polyphagous pest that damages foliage of phalsa, fig, jamun, grape vine and many other trees in arid and semi-arid region. Only the adults are destructive to fruit trees while grubs remain in soil and feed on soil humus, roots of various grasses and other vegetation growing around. Adults are noctural, feeding and mating take place at dusk and before dawn they go down in the soil. The leaf lamina is perforated by numerous small irregular holes. The damage is more pronounced in orchards grown in sandy or sandy loam soils. Adults emerge from soil with first or second showers of monsoon. Eggs are white and elongated, grubs creamy white while adults are hardy and dirty yellow. There is only one generation in year. Management: Collect.and.destroy.the beetles. This practice should-be in-the form of campaign soon after first or second shower of monsoon. Use light traps to effect and kill the beetles. Keep the orchard free from weeds. Ploughing around the trees is helpful in killing the larvae and pupae in soil. Spray the trees with monocrotophos 36 WSC 500ml or 1.0 lit. endosulfan 35 EC or quinalphos 25 EC or 1.5 Kg carbaryl 50 WP in 500 lit. water/acre. Spray should be done one day after the emergence of adults and treat all trees in the vicinity of orchard. Pests of Temperate Fruits 1. San Jose Scale Quadraspidiotus perniciosus (Comstock) (= Aspidiotus perniciosus Comstock) (Diaspididae: Homoptera) Distribution: It is indigenous to Eastern Asia and has spread to many parts of the world. It is widely distributed in all the apple growing countries of the world. It was introduced in India (Kashmir) from France in 1906 and by now it has been recorded on more than 150 host plants, including almond, apple, apricot, cherry, chestnut, citrus, crab apple, grapevine, gooseberry, mulberry, peach, pear, plum, quince, raspberry and strawberry. Nature of damage: These tiny insects suck the sap; as a result, the young plants in the nursery become weak and ultimately die away. The leaves, twigs, fruits and sometimes even the entire bark may be seen covered with ashy-grey scales which can be easily scraped off exposing the orange coloured individuals beneath. The affected fruits present pink coloured areas around the scales and the market value of such fruits is reduced.

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Life history: The nymphs hibernate from December to March, resume their activity around end of March and mature in about 4 weeks. The second stage lasts 10 - 12 days. The males (winged) fertilize the females (wingless) and die. The females do not lay eggs but produce young ones; 300 - 400 per female, the eggs mature into tiny nymphs in the female ovisac in about a month, during April - May. Nymphal period varies between 40 - 50 days. The number of generations in a year depends mainly on elevation and climatic conditions. There are six to seven overlapping st

generations in a year. The 1 instar crawlers are the main dispersal phase and are carried for a few kilometers by the wind. Management strategies: (i) Spraying the dormant trees in winter with 3% miscible oil (*Dormant oil). (ii) In addition to spraying, the parasitoid, Encarsia pernicoisi (Tower) may also be released to check the over wintering population of San Jose scale on wild host plants growing around. * Dormant oil: These are heavy and less refined oil suitable for application on fruit trees and shrubs during dormant season when they will be devoid of leaves. These are available in emulsifiable forms having 85 – 95% of actual oil. 2. Wooly aphid Eriosoma lanigerum (Hausman) (Aphididae: Homoptera) Distribution: It is native of America and is cosmopolitan in distribution except for hotter parts of the tropics. In India, it was first recorded in 1889 at Conoor (Tamil Nadu) damaging young apple trees and has since then, spread to all the apple growing areas of India. Its alternate hosts in India include crab apple, pear and quince. The pest is active throughout the year. Nature of damage: It attacks primarily the underground roots but winged form also attacks trunk, branches, stems, twigs, leaf petioles and fruit stalks. Upward and downward migrations are accentuated during hottest and coldest seasons respectively. Maximum migration from roots to aerial parts takes place in May and in the opposite direction during December - January. Due to the desapping caused by this pest, the affected trees present a sickly appearance, lose vigour and the growth of these trees as also their fruiting capacity are adversely affected. In case of young tees, the roots disintegrate to such an extent that these trees are easily blown over by even moderately strong winds. Life history: The pest overwinters either as egg or young nymph on the roots of the host tree. The eggs hatch and the nymphs mature during spring. The reproduction during this period is parthenogenetical as well as viviparous. A single female produces 30 - 116 young ones in her life time. New nymphs soon settle down in batches and start sucking the plant sap. Within 24 hours, these nymphs begin to secrete wooly filaments of wax over their bodies – hence the name, wooly aphid. Nymphal period is about 11 days in June which gradually increases with fall in temperature and becomes 93 days by December. During summer and early monsoon months there is rapid multiplication both on stems and roots and considerable dispersal of pest. The winged adults fly away while the wingless forms are blown off by the wind. With the advent of winter, the sexual forms appear, mate and lay eggs; while the immature nymphs on the trees descend and enter the root zone for hibernation. Management strategies: (i) Soil application (80 - 100 mm deep) of dimethoate or thiometon granules @ 15g / tree during spring and summer against the root forms. 182

(ii) Foliar spraying with 0.03% dimethoate or phosphamidon or oxydemeton methyl during March – April (spring) and again in June. (iii) The aphid population can also be effectively checked by an exotic parasitoid, Aphelinus mali Hald. 3. Fruit fly Dacus ciliatus (Loew) (Tephritidae: Diptera) Distribution: Dacus ciliatus commonly called Ethiopian melon fly is of African origin, now widely distributed in European countries, Africa, Middle East, Pakistan, Bangladesh, India, and Srilanka. Its main hosts are cucurbits, including various melons and alternate hosts are, citrus, apple, etc. Nature of damage: Female flies make cavities on fruits with their ovipositor and lay 3 - 8 eggs in each cavity. On hatching, maggots feed on the pulp. The affected fruits gradually rot and fall down. Life history: Eggs are shiny white, slightly curved and about 2.5 mm long. Egg stage lasts for 2 - 4 days. Maggots are whitish in colour and 8 mm long. Larval stage lasts for 4 – 6 days. Pupae are cylindrical, brownish to ochraceous in colour and about 5.5 mm long. Pupal stage is completed in 8 - 10 days. Adult flies are ferruginous-brown with hyaline wings and have two th

dark spots on 4 abdominal segment. Pre oviposition period is four days. Management strategies: (i) To check the damage by these flies, fruits should be harvested before they start ripening. (ii) All the fallen and infested fruits should be collected and destroyed to prevent the carry over of the pest. (iii) Spray application of three to five rounds of profenofos 0.05 % or fenthion 0.1 % or carbaryl 0.1 % at intervals of 15 days commencing from flowering may be useful. (iv) Frequent raking of the soil under the trees or ploughing the infested fields after the crop is harvested can help in killing the pupae. 4. Apple codling moth Cydia pomonella (Linnaeus) (Tortricidae: Lepidoptera) Distribution: This pest is widely distributed throughout Europe, North America and Australia. Nearer India, it has been found in abundance in Baluchistan (Pakistan) where it causes havoc on apples and other fruits and is stated to constitute a threat to the rest of subcontinent. In India, its occurrence was reported from Laddakh. Codling moth is a notorious pest of temperate fruits, showing marked preference for apples. It is a polyphagous pest and has also been recorded on citrus, peach, pear, quince, walnut etc. Nature of damage: Eggs are laid singly on leaves, blossoms and fruits. The freshly hatched caterpillars feed on leaves for a while, then burrow inside the fruits and feed on the pulp. The entry holes become quite conspicuous as these are filled with dry brown frass and are surrounded by a dark reddish ring. The infested apples become brighter in colour than those that are not infested and also ripe prematurely. The fruits that are attacked early in the season often drop down before the crop is ready for harvest. Life history: Eggs are flattened and white in colour. Full grown caterpillars are 16 - 22 mm long and pinkish in colour. Moths are greenish to dark brown with chocolate-brown or copper 183

coloured circular markings near the tip of forewings. The colour pattern resembles bark of the tree trunk which makes the moths quite inconspicuous. Wing expanse is 18 - 24 mm. Egg, larval, and pupal periods are 4 - 12, 28 - 35 and 8 - 14 days respectively. The caterpillars of third brood over-winter by forming thick silken cocoons in which they pass the winter under loose scales of the bark of the host trees. When spring comes, the larvae become pupae inside these cocoons and the moths emerge from the cocoons during March – April. Management strategies: (i) Strict domestic quarantine is to be followed by screening of consignments of fruits to prevent the spread of the insect from Ladak to other apple growing regions. (ii) Collect and destroy the infested fruits to prevent the carry over of the pest. (iii) Application of 0.2% Pyrethrum extract is also helpful in checking the pest infestation. The protective treatment may be applied about ten days before ripening of the fruits. 5. Peach leaf curl aphid Brachycaudus helichrysi (Kaltenbach) (Aphididae: Homoptera) Distribution: In India, the pest is more serious in Kullu valley, Shimla hills and submountaneous area of Uttar Pradesh. Its preferred host is peach but it is also found on almond, apricot, plum etc. Nature of damage: Nymphs and adults suck the cell sap from leaves, petioles, blossoms and fruits. Affected leaves turn pale and curl up; blossoms wither and fruits do not develop into normal size and drop prematurely. Life history: The alternate host in cooler region is Golden rod, Erigeron canadensis Linnaeus while in plains the aphid breeds on a weed, Ageratum conyzoides Linnaeus. Eggs are cylindrical, 0.6 mm long, light green in colour when freshly laid, later turning shiny black. Nymphs are dark green in colour and the adults that feed on leaves are green while those that feed on bark are chocolate coloured. Reproduction is sexual as well as parthenogenetic. Sexual forms appear early in November in cooler regions and lay eggs which hatch in March. At lower altitudes there is no egg-laying and over-wintering is in adult stage. With the rise in temperature, there is rapid multiplication (parthenogenetically). A single female gives birth to about 50 young ones in her life time of two weeks and each of these takes about 10 days to mature during March – April and start reproducing. All these young ones are apterous, viviparous females. After producing 3 - 4 asexual generations the aphids migrate to pass summer on its alternate host. The migration takes place during mid May in plains and around July in cooler regions. Management strategies: (i) Spray with 0.03% dimethoate or oxydemeton methyl or phosphamidon or quinalphos or 0.04% diazinon or dichlorvos just before flowering (pink bud stage) and again after 7 - 10 days. (ii) Another one or two sprayings should be given when the fruit is pea-sized. In higher hills only one pre-bloom spraying is sufficient while in mid and lower hills, in addition to pre-bloom spray, a post-bloom spray (8 - 10 days after petal fall) is also necessary.

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Suggested reading: 1) Atwal A.S. & Dhaliwal G.S. 2002. Agricultural Pests of South Asia and their Management. Kalyani Publishers, New Delhi. 2) Srivastava, K.P. & Dhakiwal, G.S. 2013. A Text Book of Applied Entomology. Vol. II. Kalyani Publishers, New Delhi. 368 pp. 3) Vasantharaj David, B. & Ramamurthy, V.V. 2012. Elements of Economic Entomology. Namrutha Publications, Chennai. 390 pp. 4) Verma L.R., Verma A.K. & Goutham D.C. 2004. Pest Management in Horticulture Crops : Principles and Practices. Asiatech Publications. Model Questions Q.1) Pin holes at the tip of berries and infested berries may fall due to injury or secondary infection.of a) Coffee berry borer b)Coffee green scale b) Coffee white borer d) None Q.2) Which of the following is a monophagous pest of Mango a) Red ant b)Fruit fly c) Nut Weevil d) Stem borer Q.3.) ‗T‘ shaped marking on marble sized fruits of mango is characteristic symptom of a) Hopper b) Leaf webber c) Mealybug d) Nut weevil Q.4) Raking of the soil around the base of the tree and application of a sticky band (crease painting) round the tree-trunk is done for the management of a) Mango mealybug b)Fruitfly c) Stone weevil d) Cashew stem borer Q.5) Which of the following pest belong to family-Miridae a) Cosmopolites sordidus b) Helopeltis antonii c) Nephopteryx eugraphella d) Drosicha mangiferae Q.6) Which of the following is true with respect to management of Anar butterfly in Pomegranate a) Pruning of twigs and branches b) Covering the fruits with polythene or paper bags c) Raking the soil d) Deep summer ploughing Q.7) Which of the following pests belong to family- Curculionidae a) Cosmopolites sordidus b) Odoiporus longicollis c) Sternochetus mangiferae d) All the above Q.8) Which of the following pest is a vector of the ―bunchy top disease‖ in banana and ―Katte disease‖ in cardamom a) Quadraspidiotus perniciosus b) Odoiporus longicollis c) Brachycaudus helichrysi d) Pentalonia nigronervosa Q.9) Encarsia pernicoisi is a parasitoid used to control a) Banana aphid b) Mango stem borer

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c) Sanjose scale

d) Apple wooly aphid

Q.10) Which of the following is true with respect to damage caused by apple wooly aphid a) It attacks primarily the underground roots but also attacks trunk, twigs etc. b) Causes ashy coat on apple stem with galled roots c) Both a & b d) None Q.11) Match the following Pest A. Coffee Berry Borer B. Peach leaf curl aphid C. Anar Butterfly D. Tea Mosquito bug E. Coffee Green scale a) A-1, B-2, C3-, D-4, E-5 c) A-3, B-2, C-1, D-4, E-5 Q.12) Match the following Common Name A. Green scale B. Rhizome weevil C. Sapota Leaf webber D. Tea-mosquito bug E. Anar butterfly a) A-1, B-3, C-4, D-2, E-5 c) A-1, B-3, C-2, D-4, E-5 Q.13) Match the following Pest A. Banana rhizome weevil B. Mango mealybug C. Coffee white borer D. Mango hoppers E. Mango fruit fly a) A-1, B-3, C-2, D-5, E-4 c) A-5, B-2, C-4, D-1, E-3 Q.14) Match the following Scientific Name A. Cosmopolites sordidus B. Eriosoma lanigerum C. Cydia pomonella D. Dacus ciliatus E. Helopeltis antoni a) A-1, B-2, C-3, D-4, E-5 c) A-2, B-4, C-3, D-1, E-5 Q.15) Match the following Scientific Name A. Cosmopolites sordidus

Family 1. Scolytidae 2.Aphididae 3. Lycaenidae 4. Coccidae 5. Miridae b) A-5, B-2, C1-, D-3, E-4 d) A1-, B-2, C-3, D-5, E-4

Scientific Name 1. Coccus viridis 2. Helopeltis theivora 3. Cosmopolites sordidus 4. Nephopteryx eugraphella 5. Deudorix isocrates b) A-5, B-2, C-1, D-4, E-3 d) A-5, B-1, C-2, D-4, E-3

1.

Place of Oviposition Flower buds and inflorescence stalk 2. In soil at depths of about 5 - 15 cm 3. Fruits 4. Crevices of the bark on stem 5. Root stock or leaf sheath

b) A-4, B-1, C-2, D-5, E-3 d) A-1, B-4, C-2, D-5, E-3

Order 1. Diptera 2. Coleoptera 3. Homoptera 4. Lepidoptera 5.Heteroptera b) A-2, B-3, C-4, D-1, E-5 d) A-5, B-4, C-3, D-2, E-1

Host crop 1. Banana

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the

B. Sternochaetus mangiferae C. Cydia pomonella D. Virachola isocrates E. Helopeltis antonii a) A-1, B-3, C-2, D-5, E-4 c) A-1, B-4, C-3, D-5, E-2 Q.16) Match the following Common Name A. Mango fruit fly B. Anar butterfly C. Codling moth D. Coffee berry borer E. Banana rhizome weevil a) A-5, B-4, C-3, D-2, E-1 c) A-3, B-5, C-4, D-2, E-1 Q.17) Match the following Common Name A. Codling moth B. Stone/ Nut weevil C. Berry borer D. Wooly aphid E. Fruit fly a) A-1, B-2, C-3, D-4, E-5 c) A-2, B-1, C-3, D-5, E-4 Q.18) Match the following Scientific Name A. Sternochaetus mangiferae B. Eriosoma lanigerum C. Bactrocera dorsalis D. Nephopteryx eugraphella E. Hypothenemus hampei a) A-1, B-2, C-3, D-4, E-5 c) A-5, B-4, C-3, D-2, E-1 Q.19) Match the following Common Name A. Mango mealybug B. Mango fruit fly C. Apple wooly aphid D. Sanjose scale

2. Guava 3. Apple 4. Mango 5. Pomogrenate b) A-2, B-4, C-3, D-5, E-1 d) A-1, B-4, C-3, D-2, E-5

Place of pupation 1. Corm/Rhizome 2. Berries 3. Bark 4. In the fruit or on fruit stalk 5.Soil b) A-3, B-4, C-5, D-2, E-1 d) A-1, B-2, C-3, D-4, E-5

Scientific Name 1. Sternochaetus mangiferae 2. Cydia pomonella 3. Eriosoma lanigerum 4. Bactrocera dorsalis 5. Hypothenemus hampei b) A-2, B-1, C-3, D-5, E-4 d) A-2, B-1, C-5, D-3, E-4

Family 1. Aphididae 2. Scolytidae 3. Curculionidae 4. Phycitidae 5. Tephritidae b) A-3, B-1, C-5, D-4, E-2 d) A-3, B-2, C-5, D-1, E-3

Management 1. Sticky band on trunk 2. Encarsia perniciosi 3. Aphelinus mali 4. Methy eugenol trap

a) A-1, B-4, C-3, D-2 c) A-4, B-3, C-2, D-1 Q.20) Match the following Common Name A. Mango hoppers B. Mango flower webber C. Mango gall midge

b) A-1, B-2, C-3, D-4 d) A-2, B-1, C-3, D-4

Family 1. Cerambycidae 2. Cecidomidae 3. Noctuidae

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D. Mango stem borer

4. Cicadellidae

a) A-3, B-1, C-4, D-2 c) A-4, B-2, C-3, D-1

b) A-3, B-4, C-1, D-2 d) A-4, B-3, C-2, D-1

Answers 1) a

2) c

3) d

4) a

5) b

6) b

7) d

8) d

9) c

10) c

11) d

12) a

13) c

14) b

15) c

16) a

17) d

18) b

19) a

20) d

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MAJOR INSECT PESTS OF PLANTATION CROPS AND THEIR MANAGEMENT HD Kaushik Department of Entomology CCS HAU Hisar The important plantation crops grown commercially in Asia are the various palm trees, namely coconut (Cocos nucifera L.), areca nut (Areca catechu) and other trees and shrubs like rubber, coffee, tea and cashew nut. The plantation crops are mostly grown in the tropics between 20°N and 20°S, and contribute substantially to the economy of several countries in this belt. All these crops have been reported to be attacked by a number of insect pests. A) Coconut 1. Rhinoceros beetle: Oryctes rhinoceros L. (Scarabaeidae: Coleoptera) The adult beetle is known as "Rhinoceros beetle" because it has a pointed horn on the head. The body of the beetle is robust and elongate measuring about 5 cm. Unlike other beetles, the wings are well developed and it is a good flier. The adult beetle is one of the most destructive pests which feeds on the crown of the coconut trees. The larvae are harmless. It is widely distributed in India and persistent in all coconut growing areas. It also attacks coconut, oil palm, date palm, sugarcane, banana, sisal, pineapple, papaya etc. Identification: Oval creamy white egg in manure pits or decaying vegetable matter at a depth of 5 to 15 cm. Full grown grub is 9-10 cm long, stout, fleshy, dirty white, curved (C- shaped) with brownish head. Tail end dark, body segments wrinkled. found at a depth of 5 to 30 cm.Grub pupates in earthern cells at a depth of 0.3 to 1 m. Adult beetle is stout, measuring 35-50 mm in length, shiny and black above and reddish brown and hairy ventrally and has a long horn projecting dorsally from the head in male. Horn is short in female. Adult lives for more than 200 days under favourable conditions. Beetles are attracted to light. Life history: Each female beetle lays about 100 to 150 oval eggs, white in colour, which are laid 10-15 cm. below the soil level in decaying vegetable matter viz. decaying leaves, logs and stem of palms, rotten vegetables, old cattle dung, wet saw dust etc. The larvae emerge in about 10 to 15 days. The larval development takes about 100 to 180 days and passes through 3-instars. The full grown larva has an average length about 75 mm. The body is covered with short brownish hairs. Pupation takes place in the earthen chamber. The pupa is brown in colour and its size varies from 50 to 70 mm. The pupal period lasts for 2 to 4 weeks and even after emergence from the pupal shell the beetle remains in the cocoon for about 11-20 days before coming out of the soil. The adult beetle emerges in about 10 to 25 days. The beetles are nocturnal. There is only one generation in a year. As a result of the attack, the growing-point is cut off and the tree dies. The young trees are more seriously attacked by this beetle. In favourable climate the total life 189

cycle from deposition of eggs to emergence of the beetle lasts for 4 to 9 months. Egg laying occurs practically throughout the year. The incidence of attack is highest in the dry season i.e.December to May Nature of damage:  The beetle injures the trees by boring into the central shoots, spathes and petioles. The boring beetle chews the internal tissues and after ingesting the juicy part throws out the fibrous part which is indicative of the presence of the beetle in the crowns.  Holes with chewed fibre sticking out at the base of central spindle  Central spindle appears cut or toppled  Fully opened fronds showing characteristic diamond shaped cuttings  Frequent infestation results in stunting of trees and death of growing point in young plantations. The infestation can be easily made out by the chewed fibrous material present near holes. Management  Remove and burn all dead coconut trees in the garden (which are likely to serve as breeding ground) to maintain good sanitation.  Collect and destroy the various bio-stages of the beetle from the manure pits (breeding ground of the pest) whenever manure is lifted from the pits.  Incorporate the entomopathogen i.e., fungus (Metarrhizium anisopliae) in manure pits to check the perpetuation of the pest.  Soak castor cake at 1 kg in 5 l of water in small mud pots and keep them in the coconut gardens to attract and kill the adults.  Treat the longitudinally split tender coconut stem and green petiole of fronds with fresh toddy and keep them in the garden to attract and trap the beetles.  Examine the crowns of tree at every harvest and hook out and kill the adults.  For seedlings, apply 3 naphthalene balls/palm weighing 3.5 g each at the base of inter space in leaf sheath in the 3 inner most leaves of the crown once in 45 days.  Set up light traps following the first rains in summer and monsoon period to attract and kill the adult beetles.  Field release of Baculovirus inoculated adult rhinoceros beetle @ 15/ha reduces the leaf and crown damage caused by this beetle.  Apply mixture of neem seed powder + sand (1:2) @150 g per palm in the base of the 3 inner most leaves in the crown  Place phorate 10 G 5 g in perforated sachets in two inner most leaf axils for 2 times at 6 months intervals..

2. Red palm weevil: Rhynchophorus ferrugineus (Curculionidae :Coleoptera) Distribution: This is one of the important pests of coconut in India in Kerala, Karnataka, Goa, Tamil Nadu and Andhra Pradesh and its attack often results in the death of the palm. In addition to coconut other palms are also attacked by the weevil.

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Identification: Oval and white eggs. Light yellowish grub without legs. Reddish brown weevil has six dark spots on thorax. Male has conspicuous long snout has a tuft of hairs. Life history: The female lays eggs in wounds or cracks or soft areas in the stem and bases of leaf stalks of living palms. Egg laying may begin 3 to 5 days after the beetle emerges from the cocoon and the oviposition period of a female weevil may last up to 8 weeks and 200-500 eggs may be laid. Eggs hatch in 2-5 days. The larva bores into interior of the palm stem and feeds for about a month or more on the soft tissues. When full grown, it constructs a cocoon of long stripes of fibres woven as a compact oval cell. They pupates inside the cell. The pupal stage lasts 2 to 3 weeks and immature beetle remains another week or 10 days in the cocoon before emerging, Thereafter, the weevil comes out of the tree through a hole made earlier and pluged with fibrous material. The total life cycle from egg to emergence varies between 50- 112 days. Thus under favourable conditions there may be 1 to 6 generations in a year. Nature of damage: Few small holes with protruding chewed fibrous material and oozing out of a brown liquid from such holes, present in the tree trunk, indicate the early infestation by the pest. In the advanced stage of attack the central shoot showssign of wilting and a large mass of grubs, pupae and adults of the insect could be seen inside the trunk at the affected portion. In the grown up trees the crown region alone is infested. Management strategies:  Remove and burn all wilting or damaged palms in coconut gardens to prevent further perpetuation of the pest.  Avoid injuries on stems of palms as the wounds may serve as oviposition sites for the weevil. Fill all holes in the stem with cement.  Avoid the cutting of green leaves. If needed, they should be cut about 120 cm away from the stem.  Fill the crown and the axils of top most three leaves with a mixture of fine sand and neem seed powder or neem seed kernel powder (2:1) or lindane 1.3 D (1:1 by volume) once in three months to prevent the attack of rhinoceros beetle damage in which the red palm weevil lays eggs.  Plug all holes and inject pyrocone E or carbaryl 1% or 10 ml of monocrotophos into the stem by drilling a hole above the points of attack.  Setting up of attractant traps (mud pots) containing sugarcane molasses 2½ kg or toddy 2½ litres + acetic acid 5 ml + yeast 5 g + longitudinally split tender coconut stem/logs of green petiole of leaves of 30 numbers in one acre to trap adult red palm weevils in large numbers.  Install pheromone trap @ 12 per ha 3. Black-headed caterpillar: Opisina arenosella (Wlk.) (Cryptophasidae: Lepidoptera) Distribution: One of the pests of importance on coconut all over peninsular India but more injurious along the east and west coasts. Identification: Caterpillar is greenish brown with dark brown head and prothorax, and a reddish mesothorax. It has brown stripes on the body. It pupates inside the web itself in a thin silken cocoon. Adult is a greyish white moth measuring 10-15 mm long and 20-25 mm in wingspan across outstretched wings. Female with long antenna and three faint spots on the forewings. Male with fringed hairs in hind wings in apical and anal margin.

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Life history: Each moth lays about 100 to 125 eggs in clusters on the tips of the older leaves. The eggs are pale yellow or cream coloured but later become pink. The larva emerges in about 5 days which is extremely small about 1.5 mm. A full grown larva measures about 12 to 15 mm before pupation. The caterpillar feeds on the green matter and makes silken tunnel. About 35 to 40 days are required for full development; the larva later on transforms itself into a brownish pupa within the tunnel. In about 10 to 12 days, a moth emerges which is white in colour. The old moth is ash-grey in colour measuring about 8 to 15 mm. The damage is caused by caterpillars which .coristruct a large number of tunnels when feeding on leaves thus causing leaves to dry, Heavy infestation causes a considerable loss of yield of coconuts. Nature of damage: The larvae live on the under surface of leaflets within galleries of silk and frassy material and feed by scraping the green matter. In case of severe attack due to large scale drying of leaflets the whole plantation presents a burnt up appearance from a distance. Management strategies:  Among the larval parasitoids, the bethylid Goniozus nephantidis is the most effective in controlling the pest.  The optimum level of release is 1:8 of host-parasitoid ratio.  The parasitoid should be released @3000/ha under the coconut trees when the pest is in the 2nd or 3rd instar larval stage. Parasitoid release trap may be used to release the parasitoid at the site of feeding.  Parasitoids should not be released in the crown region since they will be killed by predators like spiders and reduviid bugs.  Remove and burn all affected leaves/leaflets.  Spray malathion 50 EC 0.05% (1mi/lit) to cover the undersurface of the leaves thoroughly in case of severe epidemic outbreak of the pest in young palms. Root feeding for the control of coconut black headed caterpillar  Select a fresh and live root  Cut sharply at an angle and insert the root in the insecticidal solution containing monocrotophos 36 WSC 10 ml + water 10 ml in a 7 x 10 cm polythene bag.  Secure the bag tightly to the root with a cotton thread.  Twenty four hours later, check whether there is absorption.  If there is no absorption select another root.  These methods should not be resorted to as a routine practice and it is suggested only for cases of severe epidemic outbreak of the pest and when the survival of the tree is threatened. Note: Before administering the chemical the mature nuts should be harvested. After root administration there should be a gap of at least 45 days for harvest of nuts.

4. Cocconut Weevil Diocalandra frumenti (Coleoptera : Curculionidae) The grubs of this weevil attack coconut palm, date-palm, the oil and nipa-palms and sorghum. The pest is recorded from Sri Lanka, Myanmar, South India, Malaysia, Thailand, Indonesia and the Philippines. The adults are small weevils (6-8 mm in length) shiny blackish with four large reddish spots in the elytra. 192

Life-cycle: Eggs are laid in crevices at the base of the adventitious roots at the foot of the trunk, flowers, petiole or at the base of the peduncle. The eggs hatch in 4-9 days. Larval development takes 8-10 weeks and the pupal period lasts 10-12 days. The life-cycle is completed in 10-12 weeks. Damage: The grubs attack all parts of the coconut palm particularly the roots, the leaves, and the fruit stalks. As a result of this attack there is premature fruit-fall. The loss of yield is appreciable. Management: Spray 2.0 kg of carbaryl 50 WP or 500 ml of fenitrothion 50 EC in 500 litres of water per ha. 5. Coconut White Grub Leucopholis coneophora (Coleoptera:Melolonthidae) It is a major pest of coconut, tapicoa, yam, colocasia, sweet potato and banana in South India, particularly in Kerala. The Adult: Brown coloured beetle with striated wings not covering the abdomen fully It has an annual life cycle with a grub period of 8 months. Peak grub population is observed from Sept. to Oct. Adult beetles emerge out of the soil after pre- monsoon showers in May-June during sunset hours. Symptoms of damage: The white grubs are mostly found in sandy loam tracts of Kerala and Karnataka. It damage the roots. In seedling, it tunnels in to the bole and collar region.  Leaves turn yellow  Premature nut shedding  Flowering delayed  White grubs are exposed when base of tree dug Management  Plouging and digging of soil during pre and post monsoon period will expose the insect for predation.  Collect and destroy the adult beetles attracted to trees like neem, Ailanthus and Accasia on the receipt of monsoon showers  Plant neem twigs with leaves in coconut gardens after rain to attract and kill adult beetles  Set up light trap @ 1 / ha or bonfire  Application of phorate 10G @ 100g per palm should be mixed and raked in the top 15cm soil in May-June and Sept.-Oct. Irrigation is necessary after the pesticide application. 6. Coconut Scale Aspidiotus destructor (Hemiptera Diaspididae) The coconut scale is one of the most dangerous pests of coconut palm in most of the coconut growing regions. It occurs from Iran to Japan, and USA, and southwards down to South Africa and Australia. In addition, this pest also feeds on other palms, bananas, avocado, cocoa, citrus, ginger, guava, papaya, rubber, sugarcane, yam and many wild plants. The scale of the female is circular, flat, transparent, whitish to grey white and about 1.8 mm in diameter. The scale of the male is oval and much smaller than that of the female. Life-cycle: The female deposits about 20-25 yellow, tiny eggs under her scale. Incubation takes 7-8 days. On hatching, the crawler takes up a position on the leaf and starts feeding. The male nymph moults three times and the female twice. The larval development takes 24 days. The total 193

life-cycle is completed in 31-35 days and there are about 8-10 generations per year. Damage: Scales feed by sucking sap from the plant cells whilst secreting toxins from their salivary glands in the process. Continuous feeding causes drying up of leaflets giving a yellow colour initially then turning brown in advance cases. In extreme cases, the leaves dry up, entire fronds drop off, the crown dies by total cessation of the photosynthesis process and the whole crop is lost. Management: Spray 500 ml of malathion 50 EC in 250 litres of water per ha. The coccinellid predators including Chi/ocorus sp., Azya trinitalis Mshl., Cryptognatha nodiceps Mshl., Rhyzobius lophanthae (Blaisdell) and Pentilia castanea Muls. (Coccinellidae) playa significant role as natural limiting factor for the coconut scale. The nymphal parasites belonging to genera Comperiella (Encyrtidae) and Encarsia sp. (Aphelinidae) have a more local significance. 7. Coconut Eriophyid mite: Aceria guerreronis Eriophyidae: Acarina It became a threat to coconut in south India causiong economic losses. The microscopic wormlike eriophyid mites are seen in thousands under inner bracts of the perianth. They also feed in colonies on lower leaf surface causing yellow speckling and chlorosis. Identification of the pest  Nymph and Adult - Pale in colour with elongate body and worm like appearance Symptoms of damage  Triangular pale or yellow patches close to perianth which turn into brown patches with longitudinal fissures and splits on the husk (warting)  Necrotic tissues  Shedding of butons  Brown colour patches, longitudinal fissures and splits on the husk  Oozing of the gummy exudation from the affected surface  Reduced size and copra content  Malformed nuts with cracks and hardened husk. Management  Apply urea 1.3 kg, super phosphate 2.0 and muriate of potash 3.5 kg/palm/year  Neem cake @ 5 kg and organic manure 50 kg/palm/ year  Borax 50 g + gypsum 1.0kg + Manganese sulphate 0.5 kg/palm/ year  Grow intercrop (sun hemp, four crops/year) and shelter belt with casuarina all round the coconut garden to check further entry  Triazophos 40 EC 5 ml/lit or monocrotophos 36 WSC @ 2 ml / lit or carbosulfan 25 EC 2 ml/ lit in alternation with neem azal 1% 5ml/lit as spot application  Spraying twice at weekly interval on buttons and developing nuts on bunches with wettable sulphur 6g/l or prophanophos 5ml/l or methyl demeton 6ml/l or triazophos 5ml/l ii. Root feeding Monocrotophos 36 WSC @ 15ml or triazophos 40 EC @15 ml or carbosulfan 25EC @ 15 ml / 15 ml of water  After root feeding, next harvest should be done 45 days later. 

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8. Slug caterpillars: Contheyla rotunda, Macroplectra nararia, Latoia lepida (Lepidoptera :Limacodidae) It is a sporadic pest. C. rotunda is common in west coast, while M. nararia is common in Godavari district of Andhra Pradesh. Mango, castor, cashew, pomegranate are other hosts. The caterpillar feeds on leaves, buds, flower shoots and developing fruits. Caterpillar is fleshy, slug like with series of tufts of spines highly irritating to touch, hence called ―nettle grub‖. Pupation takes place in hard shell like grayish cocoon Management: · Clipping the affected leaves along with the larvae. · Natural parasitisation occurs with larval and pupal parasites. · Bacterial and fungal infections on larvae and pupae are common in rainy season. · Spray application of carbaryl 3 g/l or root feeding with monocrotophos is effective 9. Termite: Odontotermes obesus Termitidae: Isoptera Damage:Termites damage the seedlings in the nursery and transplanted seedlings. Wilting of central shoot is a symptom of the attack. Up to 20% of the seedlings are destroyed by the termites in the laterite soils. Base of trunk is seen plastered with runways made of soil and fibre. Management:Locating termite mounds in or near the coconut nursery or garden, digging out the termitarium and destroying the queen, drenching the soil with chlorpyriphos 10 ml/l of water are effective measures. B) Coffee (Coffea arabica) 1. Coffee white borer Xylotrechus quadripes Ch. (Cerambycidae: Coleoptera) Distribution: The insect is considered to be one of the important pests of coffee in different parts of India. Nature of damage: The grubs burrow into the stem for 8 - 9 months and cause wilting of branches and occasionally death of bushes. It is a serious pest of Arabica coffee. Infested plants show external ridges around the stem. Affected plants also show yellowing and willing of leaves. Life history: The beetle has white cross hands and dark brown elytra. The adults emerge in large numbers at two distinct periods viz., April-May and October-November. A beetle lays about 50 100 eggs in crevices of the bark on stem. The grubs hatch out from the eggs in 8 - 10 days and pass through the larval stage for 8 - 9 months. Pupation takes place in the stem itself and pupal stage lasts for 25 - 30 days. Management strategies: (i) Maintain optimum shade. (ii) The wilting branches and bushes should be removed and destroyed. (iii) Lindane 20 EC @ 1300 ml in 200 litres of water with 200 ml wetting agent may be swabbed over the stem once in April - May and twice at an interval of a month during October December for effective control of infestation by the pest or 0.05% monocrotophos or phosalone. 2. Coffee Berry Borer Hypothenemus hampei (Ferrari) (Scolytidae: Coleoptera) Distribution : Central and South America, Mexico, Ecuador, Indonesia, Kenya, India, Srilanka, Korea, Malaysia, Thailand, Viet Name, Congo, Ethiopia, Ghana etc. In India it is distributed in Kerala, Tamil Nadu and Karnataka.

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Nature of damage: Pin holes at the tip of berries. In severe cases of infestation two or more holes may be seen. Infested berries may fall due to injury or secondary infection. Severe infestation may result in heavy crop loss up to 40 - 80%. Life history:Adult females bore a hole in coffee berries and lay their eggs near the two coffee beans found inside the berry. Once the eggs hatch, the larvae feed on the beans rendering them unfit for commerce or lowering their quality. The total life cycle is completed in 25 - 30 days. Management strategies: (i) Timely and clean harvest. Use mats to prevent gleanings. (ii) Remove off-season berries and gleanings. (iii) Spot spray 0.07% endosulfan 35 EC when most of the beetles are waiting near the naval region of fruit. (iv) Dry coffee to prescribed moisture level (arabica / robusta parchment 10%, arabic cherry 10.5% and robusta cherry 11%). (v) Mass trapping of beetles with coffee fruit extract in 1 : 1 combination of ethanol and methanol. 3. Green scale Coccus viridis (Gr.) (Coccidae: Homoptera) Distribution: Found in different coffee growing regions in India. Nature of damage: The scale is 3 mm long, flat, yellowish green ovate and slightly convex and covers the tender leaves and shoots and sucks the sap. Sometimes it becomes serious affecting the vigour of the bushes considerably and sooty mould development is commonly noticed affecting photosynthesis. It causes debilitation of older plants and death of nursery plants. Management strategies: (i) Maintain optimum shade. (ii)Spray application of Malathion 0.1% or methyl parathion 0.05% or profenofos 0.05 % or phosalone 0.07%. C). Pests of Tea (Camellia chinesis) Tea-mosquito bug Helopeltis theivora Waterhouse (Miridae: Hemiptera) Distribution: It is considered to be a serious pest of tea particularly in Kerala. The pest has been reported from India, Indonesia and Indo-China. Nature of damage: The nymphs and adults suck the sap from tender buds, leaves and stem and the toxic saliva of the insect injected at the time of feeding cause brownish patches and curling of leaves and ultimate drying of the shoots. Life history: It is a slender insect, 6 - 8 mm long, with a yellowish-brown head and abdomen, a dark–red thorax, and long dark appendages. The prothorax has a prominent and characteristic clubbed horn. The elongate and sausage shaped eggs are also peculiar in possessing two filamentous long processes which remain jutting out from the tender plant-tissue in which the eggs are embedded by the female. The eggs are laid practically in all tender parts of the plant. The incubation period varies within wide limits (5 - 27 days). The freshly-hatched nymphs are rather spidery in general appearance due to their elongate appendages. They undergo five moults to become adults and the time required for the completion of one generation varies from about two weeks in June to eight weeks or more in the cold weather. Management strategies: (i) Monitoring the infestation level in the field. (ii) Removal of stalks containing eggs while plucking. (iii) Encouraging the egg parasitoid, Erythmelus helopeltidis population to build up. 196

(iv) Application of endosulfan 35 EC @ 1000 ml/ha or quinalphos 25 EC @ 750 ml/ha or chlorpyrifos 20 EC @ 750 ml/ha or fenthion 80 EC @ 200 ml/ha or quinalphos 25 EC + dichlorvos 76 EC @ 750+250 ml/ha. Spraying may be undertaken during early mornings or evenings when these bugs are active. D) Cashew nut (Anacardium occidentale L.; Family : Anacardiaceae) 1. Cashew tree borer, Plocaederus ferrugineus Linnaeus (Coleoptera : Cerambycidae) Identification : When full-grown, the larva measures 7.5 cm. The adult is a medium-sized dark brown beetle. Life cycle:The beetle lays eggs under the loose bark on the trunk. The newly emerged grubs bore into the bark and feed on soft tissues, making tunnels in all directions. The grown up grubs may also feed on wood and tunnels its way to the root region, where it forms a calcareous shell for pupation. The life cycle is completed in more than a month and there are several overlapping generations in a year. Damage: The borers damage the cambial tissues and hence the flow of sap is arrested. The tree is weakened and if infestation continues it may die. Management: 1. Drench the basal trunk and the root with 1.25 litres of lindane 20 EC in 250 litres of water per ha. 2. Inject carbon disulphide into the tunnels and plaster them with mud. Other pests of Cashew nut The other pests of cashewnut include: 1. Mealy bug, Planococcus lilacinus (Cockerall) (Hemiptera : Miridae); 2. Tea mosquito bug, Helopeltis antonii S. (Hemiptera : Miridae); 3. Wax scale, Ceroplastes floridensis Comstock and Coccus hesperidum Linnaeus (Hemiptera : Coccidae); Catacanthus sp. (Hemiptera : Pentatomidae); 4. Castor thrips, Retithrips syriacus M, grapevine thrips, Rhipiphorothrips cruentatus Hood and the cashew thrips, Selenothrips rubrocinctus G. (Giard) (Thysanoptera : Thripidae); 5. Leaf miner, Acrocercops syngrammia Meyrick (Lepidoptera : Gracillariidae); 6. Bark borer, Indarbela tetraonis M. (Lepidoptera : Metarbelidae); 7. Castor slug caterpillar, Parasa lepida (Cramer) (Lepidoptera : Limacodidae); 8. Indian meal moth, Plodia interpunctella (Hubner) and the fig moth, Ephestia cautella (Walker) (Lepidoptera : Pyralidae); 9. Leaf caterpillar, Cricula trifenestrata H. (Lepidoptera : Saturniidae); 10. Weevil, Myllocerus viridanus Fabricius (Coleoptera : Curculionidae) and the shoot weevil, Apion ampulum Fst. (Coleoptera : Apionidae). E) Areca nut (Areca catechu L. Family: Aracaceae) 1. Areca nut mirid bug : Carvalhoia arecae Miller & China (Hemiptera: Miridae) Identification: The nymphs are greenish with reddish brown patches. The adult is a red and black bug measuring 6 mm long and 2.5 mm wide. Life cycle : The female bug lays eggs singly into the tissues of the tender unopened leaves of the palm. The eggs are oval, with two-bristle like structures arising from the operculum. The eggs hatch in 9 days and the young nymphs suck cell sap from tender parts. The nymphs become adults in 2-3 weeks after undergoing 5 moultings.

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Damage: The nymphs and adults suck sap from the tender leaves of arecanut palm. The bugs remain clustered together within the top most of the leaf axils. In case of severe infestation, the leaves get shredded and stand erect. Continued attack over a number of years results in stunted growth of the palm and the yield is also reduced. Management : Spray 250 ml of monocrotophos 36 SL or 375 ml of quinalphos 25 EC in 250 litres of water per ha at monthly intervals especially on the spindles and young fronds. Other pests of Areca nut The other pests of areca-palm include : 1. Grasshopper, Aularches miliaris Linnaeus (Orthoptera : Arcididae); 2. Termite, Odontotermes obesus (Rambur) (Isoptera : Termitidae); 3. Aphids, Cerataphis lataniae (Boiduval) and C. variabilis H. R. L. (Hemiptera : Aphididae); Coccus hesperidum Linnaeus (Hemiptera : Coccidae); Dysmicoccus brevipes (Cockerell) (Hemiptera : Pseudococcidae); 4. Leaf thrips, Rhipiphorothrips cruentatus H. And the flower thrips, Thrips hawaiiensis (Morgan) (Thysanoptera : Thripidae) 5. Nut beetle, Araecerus fasciculatus DeG (Coleoptera : Anthribidae); Rhynchophorus ferrugineus (Olivier) and Diocalandra stigmaticollis Gyll. (Coleoptera : Curculionidae); 6. Stored arecanut beetle, Coccotrypes carpophagus Horn. (Coleoptera : Scolytidae) 7. Mites, Oligonychus indicus Hirst; O. biharensis Hirst (Acarina : Tetranychidae) and Raoiella indica Hirst (Acarina : Tenuipalpidae) Suggested reading: Atwal A.S. & Dhaliwal G.S. 2002. Agricultural Pests of South Asia and their Management. Kalyani Publishers, New Delhi. Srivastava, K.P. & Dhakiwal, G.S. 2013. A Text Book of Applied Entomology. Vol. II. Kalyani Publishers, New Delhi. 368 pp. Vasantharaj David, B. & Ramamurthy, V.V. 2012. Elements of Economic Entomology. Namrutha Publications, Chennai. 390 pp. Verma L.R., Verma A.K. & Goutham D.C. 2004. Pest Management in Horticulture Crops : Principles and Practices. Asiatech Publications.

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MAJOR NON INSECT-PESTS OF AGRICULTURAL CROPS (RODENTS, BIRDS ETC.) Sunita Yadav Department of Entomology CCS HAU Hisar Quality of agricultural produce and environment along with sustainability are the keywords for the agricultural development in the country. Non-insect pests have vital linkages with the sustainability of the Agricultural Production Systems. The exact role of non insect-pests like rodents, birds, mites and mammals as pests of crops is not yet clearly understood. Non insect pests cause much harm to the agricultural crops both in the field as well as in the post harvest storage. The information on the loss due to these pests and their control are discussed below: RODENTS Rodents (Latin rodere, to gnaw) are mammals of the order Rodentia, characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. Well known rodents include mice, rats, bandicoots, gerbils and porcupines. They are omnivorous and are number one competitor of man. They are very choosy and would not eat the spoiled food because they cannot vomit. The rodents can be diurnal, nocturnal, arboreal or terrestrial and show bimodal feeding activity that is showing one peak during the morning and the other during evening. The rodent fauna of India comprised of 34 species and 265 sub species belonging to 36 genera and 6 families. Rodents damage various crops of the kharif season that includes jowar, maize, groundnut and cotton, etc., as well as the crops like wheat and barley of the rabi season. They are fossorial and make their burrows inside the fields and thus affecting the roots of the crops. They attack shortly after sowing during vegetative growth and during ripening of the seed heads. They make their burrows on the banks of the rivers and irrigation canal. The banks are so much honey combed that there is the seepage of water and ultimately it results into the undesired flooding of different areas and loss of water. Most of the rodents have blood sucking parasite. They pose a very serious threat to the public health and are involved in the transmission of many contagious diseases including plague. Rodents are of two types namely Commensel rodents and Field rodents A. Commensel Rodents The word commensal is used to describe rodents that are generally found living in close associations with humans and very often dependent upon human habitat for the essential elements of food, water, shelter and space. The rodent species we normally categorize as commensal are the house mouse, Norway rats and roof rats. 1. House mouse (Mus musculus) (Muridae:Rodentia) The common house mouse and a miniature replica of R. rattus in looks, it measures 5-7 cm with an equally long tail and 18 g weight. Its dorsum is dark brown on sandy brown and venter offwhite, grey or dark brown. It is cosmopolitan in distribution, nocturnal and fossorial (burrowing) 199

in habit, can live indoors and in fields and is a close associate of R. rattus in houses and godowns, and a great destroyer of textiles, sacs, paper, etc. It is quick, tends to nibble and run rather than stay longer at food source. They can pass through a hole slightly less than 1.25 cm. They produce 6-10 litter per year with 6-10 young ones per litter. They can climb easily and also can swim when necessary. 2. House/Roof/Black rat (Rattus rattus) (Muridae:Rodentia) It is distributed all over India & the world and is excellent climber and swimmer. Its body (head and' trunk together) measures 10-12 cm, tail slightly longer and weighs 150-200 g. Its colour has shades of brown and black on the upper side and off-white to grey on the underside. It is nocturnal in habit, does not burrow but can make nests on trees. It can occur in fields, coconut field in particular, and has a denser population in villages because of the availability of harborages. 3. Brown rat or Norway rat (Rattus norvegicus) (Muridae:Rodentia) It is found mainly at ports in tropical countries and in cities and farmlands in temperate (European) countries. Its body measures 18-20 cm with 16-18 cm long tail and 200-450 g weight. Its dorsum is brown to dark brown and venter greyish, occasionally black. It is distinguished from R. rattus by its blunt muzzle, smaller ears and tail shorter than the body length. It is predominantly a burrower and in big cities, it is specially found in sewers as it prefers wet or damp locations and so often called sewer rat. It does not close the burrow openings. B. Field Rodents The species of field rats most widely distributed throughout the country and causing damage to crops are Bandicota bengalensis, Rattus meltada, Tatera indica and Mus spp. However, in certain regions they may be outnumbered by some other species, for example, Meriones burrianae in the Indian desert and T. indica in peninsular India. With intensification of paddy cultivation during the last two decades, B. bengalensis has become the most predominant rodent in summer. According to the estimates made in wheat and groundnut fields, the population of Tatera indica is 50-75 individuals per hectare in the peak season. 1. Indian Mole Rat or Lesser Bandicoot Rat, Bandicota bengalensis (Muridae:Rodentia) This is a fierce animal and like bandicoots, have the habit of erecting piles of long hairs and grunting on being excited. A good swimmer, it is covered with thick harsh fur, greyish-brown or black on top and greyish-white on the belly. It measures 16-24 cm in length (without the tail) and the average male weighs 326 g and the female 287 g. The tail, which is scaly and has 160170 rings, is often shorter but is sometimes as long as the body. It breeds throughout the year and the number of the young per litter varies from 6 to 15. Up to 7.3 kg of wheat ears has been found hoarded in a single burrow. The burrows are underground and shallower than those made by Tatera indica. There are 2-12 openings in a burrow and they are generally closed with loose excavated soil during the day-time. The burrows are generally found in the fields of groundnut, wheat, gram, sugarcane, maize, sorghum, cotton, paddy and in fruit orchards.

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2. Soft furred field rat or grass rat, Rattus meltada (Muridae:Rodentia) It is the common field rat found all over India, Nepal and Sri Lanka. It is smaller than the mole-rat and is 12-15 cm long with equal or shorter tail and about 60 g in weight. It bears large rounded ear lobes and soft coat of fur which is light brownish-grey on the upper side and greyish-white on the underside. It is mostly found in irrigated fields, bunds, hedges and grasslands. In northern India, this nocturnal and gregarious rat produces young ones in two breeding seasons, viz. March and August. A female produces 1-4 litters during the breeding season and the interval between two litters is 20-44 days. In captivity, the number of young ones per litter varies from 1 to 8. This rat makes burrows which are smaller and narrower than those of B. bengalensis and T. indica. There are 1-4 openings to a burrow and they are always kept open, but a few bits of grasses are kept in front of the openings. In southern India, the breeding season coincides with the maturity of paddy in September-October and again in January-April. 3. Indian Field-mouse, Mus booduga (Muridae:Rodentia) It is found in dry as well as in wetlands and is a fairly good swimmer. It is brown from above and whitish or dull grey on the underside. The tail is equal to or shorter than the body and is dark above and pale below. The mouse measures 5-8 cm and weights 16-19 g. In southern India, it breeds in September-October and February-June. It makes small burrows without any branches, having only one bed chamber. The field-mice live in pairs and are common in the same habitat as of the mole- rat. The length of the burrows ranges from 50-116 cm and its diameter is 2-3 cm. The number of young ones per litter is 6-13. 4. Gerbils (Muridae:Rodentia) Gerbils, also called antelope rats differ from rats in having their tails clothed in fur (not naked like rats) and ending in a tassle. Their hind feet are much longer than rats of equal size that enable them to run by bounds. There are two species of gerbils: a) Indian gerbil, Tatera indica: 15-18 cm long tail and reddish-brown to fawn or greyish-fawn dorsum and white underside; it is noctunal in habit and lives in simple burrows with 3-10 openings, a central chamber and a few bold runs b) Indian desert gerbil, Meriones hurrianae: 17-18 cm long with equally long tail, 65 g weight and sandy-yellow to brownish-grey dorsum and dirty white venter; it is diurnal in habit and lives in extensive but unplanned burrow. 5. Squirrels (Sciuridae:Rodentia) There are a number of genera of squirrels found in India but the genus Funambulus with two species F. pennanti (five-striped palm squirrel) and F. palmarum (three-striped palm squirrel) are important from our (control) point of view. Fivestriped squirrels are predominant in the North and three-striped ones are predominant in the South. Both are diurnal and arboreal with their peaks of activity in the morning and early evening depending on man for food but also supplementing it with fruits, seeds, vegetables, crops, occasionally insects (Acridids in particular) and eggs of birds. Their damage to fruit gardens is severe. 6. Porcupines (Hystricomorpha:Rodentia) The Indian crested porcupine, Hystrix indica is the largest rodent found in our country. It occurs from the Russian Turkestan, Syria to India and Sri Lanka. It measures 65-75 cm, weighs about 10-18 kg and is covered with quills of deep brown to black and white bands alternating with each other. A long crest of bristles is present on the head and white rattling quills on its short tail. It likes to inhabit rocky 201

habitats (in caves) but is also found in stabilised sand dunes (in long burrows). It breeds from March to October with peak period during monsoon months. Its litter size is 1-3. It is mostly destructive to tuberous crops like sweet potato, potato, onions, and carrots but can also damage forest trees by girdling them. Management The various techniques to manage rodents include cultural, mechanical, biological and chemical control practices. Cultural control: Deep ploughing upto 45 cm, reduction of size and trimming of field bunds at the time of land preparation would certainly go a long way in controlling rodents. Weed management and removal of burrows reduce availability of alternative food and shelter. Simultaneous planting prevents rodent migration from harvested to unharvested fields. Mechanical control: Guarding of rat attacks by means of rodent-proof containers and plastering storage structures help in checking rodent infestation. The rodent problem can be solved to a large extent by obstructing the entry of rats in houses and stores. Trapping is an economical and effective way of reducing rodent population. Trapped rats should be killed by drowning cages in ponds and dead rats should be buried deep in the soil. The trapped rats should not be released in the fields as they usually come back to their original place. Biological control: A number of predators like snakes, owls, eagles, mongooses, etc. contribute to natural regulation of rodent population. Keeping cats in houses also checks the rat population. Chemical control: The two most commonly employed chemical control measures include poison baits and fumigation. 1. Poison baits:The most effective method of controlling rats is the use of poison baits. The poisons used in the baits are of two types: a) Acute poisons which are used in a single dose, e.g. strychnine hydrochloride, zinc phosphide, norbormide (Raticate), sodium fluoroacetate, thallium sulphate, ANTU (Alphanaphthyl thiourea); b) Chronic poisons which act as blood anticoagulants and are used in multiple doses. They include hydroxy coumarins (Warfarin, Fumarin, Tomarin, Recumin) and indandions (Pival, Radione, Valone). These poisons are lethal when consumed for several days,as they cause external and internal haemorrhage.The other anticoagulant rodenticides (Brodicacoum, Bromadiolane) are lethal in a single dose but the rats die after several days of poisoning. Zinc phosphide (2% bait) is the most commonly used rodenticide in India. The bait is prepared by mixing 1 part of zinc phosphide with 40 parts of whole or cracked grains of wheat, gram, maize, bajra or sorghum smeared with vegetable oil. Racumin bait (0.0375% bait) is more effective against the bandicoot rat than other species. The bait is prepared by mixing 50 g of 0.75 per cent racumin powder, 20 ml of groundnut or sunflower oil and 20 g of powdered sugar in 1 kg of cracked wheat or any other cereal. Another bait (0.005% Biomadiolone bait) can be prepared by mixing 20 g of 0.25 per cent Bromadiolone powder, 20 g of oil and 20 g of powdered sugar in 1 kg of any cereal flour. The mixture is wrapped in paper packets which are distributed in the field at 10-15 m distance. For better results in the field, the poison operations with zinc phosphide should be preceded by careful prebaiting, i.e., false baiting with nonpoisoned bait for 1-2 days. Field operations with zinc phosphide result in 70-80 per cent 202

reduction of rodent population. The rest of the population acquires bait shyness after a single exposure to the bait. Poison baiting with zinc phosphide should not be repeated within 2-3 months. The residual population should be controlled by the fumigation of burrows or by baiting with warfarin. 2. Fumigation of burrows: Another effective method of rat control is killing them inside the burrows by fumigation. Aluminium phosphide tablets (2 tablets of 0.6 g or half tablet of 3 g per burrow) have been found to be very effective and safe. After introducing a tablet into a live burrow, the opening is closed tight with soil. The chemical reacts with soil moisture and deadly phosphine gas is generated. These methods of killing rats are effective only when carried out on a large scale, covering large contiguous areas, and are repeated time and again. The aim should be to kill more than 90 per cent of the population, otherwise they breed so fast that population reaches the same level within a few months. BIRDS A number of birds feed upon grains from ear heads of field crops; fruits and vegetables. They actually consume very little quantity but often cause more damage than what they actually eat. Many species of birds are found throughout India, out of which some birds are considered harmful to agricultural crops. Some of them are as following: 1. Crow (Corvus Splendens): Crows cause considerable damage to ripe fruits in orchards and also ripening grains of maize and fruits. The crows are particularly attracted to the grains when they are exposed on a cob. They may prove a menace to the successful growth of field crops as well as harvest of fruits. They are often seen in flocks in maize and other fields. 2. Sparrow (Passer domesticus): The flocks of sparrows is a great menace to various field crops like Jowar, bajra, wheat, maize, etc. mainly in the seed setting stage. They also threaten mulberry and many other small sized juicy fruits and fruit buds. They visit the ripening fruit fields, particularly those of wheat in the spring season, and cause much damage both by feeding and causing the grains to shed. House sparrows consume grains in fields and in storage. They do not move long distances into grain fields, preferring to stay close to the shelter of hedge rows. Localized damage can be considerable since sparrows often feed in large numbers over a small area. Sparrows damage crops by pecking seeds, seedlings, buds, flowers, vegetables, and maturing fruits. They interfere with the production of livestock, particularly poultry by consuming and contaminating feed. In grain storage facilities, fecal contamination probably results in as much monetary loss as does the actual consumption of grain. 3. Parrot (Psittacula spp.): About eight species of parrots have been recorded in India. Out of these species, Large Indian parakeet (P. eupatria) is very common in Maharashtra. This species causes heavy damage to orchards by eating fruits and also spoiling the fruits by cutting it with beak. The parakeets are among the most wasteful destructive birds. They gnaw at and cut into bits all sorts of near-ripe fruits such as guava, ber, mango, plums, peaches, etc. In sunflower when the seeds are soft the parrots cause extensive damage by feeding on the seed thus reducing the yield 4. Baya weaver (Ploceus philippinus): It feeds on the grains when the crop is near maturity. It makes nests that are long, graceful structure of excellent woven structure. Male builds the nest to attract the female. Breeding period is May to September, and a female lays dull white 2-4 203

eggs. It is commonly found in plains of India and move in flocks. 5. Myna (Acridolheres irislis): It breeds in April-September. Nests are made in holes of walls or tree trunk with feathers, rags, twigs or leaves etc. It lays 4-6 deep blue eggs and has 2-3 generations in a year. It is a bold bird, makes noise and follows snakes, and lizards etc emitting alarm calls. They feed in small flocks but are gregarious in flight. It is found up a height of 2700m throughout India. It feeds on vegetable leaves. 6. Bulbul (Pycnonotus cafer): It breeds from February to August. Nests are made of grass, cobwebs in bushes or trees. It lays 2-4 pinkish, blotched with dark red brown eggs. Both the sexes take care of the young ones. They remain in pairs for most of the times. It is found throughout India and damage the fruits and flower in the orchards. 7. Pigeon (Columba livia): They breed throughout the year but peak period is January to May. They generally remain in pairs. Female lays 2 elongated-oval white eggs in nest made of coarse twigs. Nests are made on rock cliffs or buildings and found throughout India. They cause sufficient damage to grain crops, sprouting vegetables and cereals. Management of Birds Various methods are employed which include covering by nets, using scaring devices, reducing their population by shooting, trapping and use of chemicals. a.

Trapping the birds in nets or catching them with the help of sticky substance ‗Lassa‘.

b. The crows have a great sense of communal alarm and, if one of them is killed, the whole group creates a tremendous noise; therefore, a dead crow hanging on the top of a pole can effectively be used as a scare-crow. c. Scaring devices using mechanical, acoustic and visual means are normally employed, i.e. Beating of drums to produce sounds is still in vogue in many parts of the country particularly during harvesting. d. Fire crackers placed at regular intervals along a cotton rope. The rope burns from one end and ignites the crackers at regular interval which produce sounds and scare away the birds. e. Loud sounds due to the burning of acetylene gas produced at intervals are utilized to scare away birds and small animals. f. The periodic collection and destruction of nests would lead to reduction in their population. Egg laying period of birds is as follows: Parrot

March-June

Sparrow

April-May to Sept.-Oct.

Pigeon

May-June to Sept.-Oct

g. A piece of chapatti dipped in 0.3 per cent methyl parathion or 2 per cent fenthion placed on top of a roof is good bait for killing sparrows, Pigeon, crow etc. h. Bajra seeds soaked in 2 per cent fenthion emulsion and dried, are placed in small cups and hung from the rafters or branches of trees.

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MITES Mites belong to the order Acarina of the class Arachnida. They are very tiny creatures capable of infesting and causing severe loss to a variety of agricultural and horticultural crops particularly under dry situations. In addition to direct damage to crops they also cause in direct damage by acting as vectors of important viral diseases. Mites can be distinguished from their insect relatives by the presence of two body regions (cephalothorax and abdomen, in some these two are fused), four pairs of legs (only two pairs in Eriophyidae), sucking mouth parts and lack of antennae and wings, Mites possess chelicerae as mouth parts which are needle like useful for sucking sap from plants. Adults vary in body shape and possess 2 or 4 pairs of legs. The life cycle consists of an egg, larva, proto nymph, deuto nymph, trito nymph and adult stages. Oval shaped eggs are laid on leaves. Incubation Period is 6-13 days. The no.of nymphal instars vary among the families. The mites that feed on plants are called phytophagous mites. Around 7,000 species of plant-feeding or phytophagous mites are known worldwide which occur in five families namely Tetranychidae, Tenuipalpidae, Tarsonemidae, Eriophyidae and Tuckerillidae. In India, a total of 660 mite species are known, out of which 169 (17 as major and 30 as minor pests) are represented by phytophagous mites. In various crops, 10-15 per cent losses are reported due to spider mites and in some cases, total loss is reported. In particular, 50-80 per cent in mango 10-15 per cent in rice, 15-20 per cent in tea, 10-25 per cent in sugarcane, 13-31 per cent in brinjal, 25 per cent in okra, 27-39 per cent in chillies due to phytophagous mites is reported. Tetranychidae: These mites are generally referred to as spider mites. They are soft bodied, variously coloured, colony forming and many of these can spin webs to protect themselves from natural enemies and pesticides. There are approximately 106 species known out of which 19 species have taken a pest status. Mite feeding can cause yellowish to whitish patches on leaves, leaf bronzing, stippling or scorching. There is extensive webbing on leaf surface and black faecal dots are seen on the leaf surface. Severe spider mite infestation cause major reductions in plant growth rates, flower formation and yield. Penetration of cells by mite stylets and injection of saliva cause both mechanical damage and changes in cell cytology and physiological and biochemical processes of non-punctured adjacent cells. Due to their short life span (9-10days), high reproductive potential (100 eggs/ female), severe webbing and resistance to insecticides, they have emerged as dreaded pests of horticultural crops. There are five stages in the life cycle of these mites i.e. egg, larva, protonymph, deutonymph and adult stage. Eriophyidae (Gall/bud mites): Depending upon the damage, these are known as gall formers, bud mites, leaf rollers, erineum formers, blister mites, vagrants. Apart from these injuries, some species play a vital role in virus transmission like Pigeonpea Sterility Mosaic Disease by Aceria cajani, Wheat Streak Mosaic Disease by A. tulipae, Sugarcane Streak Mosaic Virus by A. sacchari, Fig Mosaic Virus by A. ficus etc. Tenuipalpidae (False spider mites): These mites generally feed on the ventral surface of leaves near the midrib or veins. There is bronzing and rusting symptoms on the lower surface of leaves due to feeding of nymphs and adults. Some species form galls on the leaves and stems of plants. Important mites are Brevipalpus phoenicis (coffee, rose, tea, coconut, guava, citrus), Larvacarus transitans (ber)

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Tarsonemidae (yellow mites): They usually infest the tender portion of plants and suck the sap from buds, leaves, shoots, flowers and stem sheath. They cause curling, crinkling and brittleness of foliage but shows little leaf symptoms. The injury caused by this group is often mistaken as a disease symptoms caused by pathogenic microorganisms. e.g. Polvphagotarsonemus latus (Chilli mite). Tuckrellidae: This is the smallest phytophagous family, which includes four species. These are brightly coloured having fan like dorsal body setae and long whip like caudal setae. e.g. Tuckerella sp. Important species of mites Common Name Grain Mite Mold Mite Cheese Mite House Dust Mite Chicken Mite Itch or Scabies Mite Straw Itch Mite Two-spotted spider mite Honey bees Mite Honey bee tracheal mite Broad mite/ Yellow mite Predatory mite Brown wheat mite Mange mite (In dogs) Two spotted spider mite Cucurbitaceous mite Mango mite Sorghum mite Cotton mite Paddy mite Citrus leaf mite Sugarcane mite Cocunut mite Jasmine eriophyid mite

Scientific Name Acarus siro Tyrophagus putrescentiae Tyrolichus casei Dermatophagoides sp Dermanyssus gallinae Sarcoptes scabiei hominis Pyemotes tritici Tetranychus urticae Varroa sp Acarapis woodi Polyphagotarsonemus latus Phytoseiulus persimilis Petrobia latens Demodex canis Tetranychus urticae Tetranychus cucurbitae Aceria mangiferae Oligonychus indicus Tetranychus macfarlanei Oligonychus oryzae Eutetranychus banksi Schizotetranychus andropogoni Aceria guerreonis (=Eriophyes guerreonis) Aceria jasmini

Management: Cultural control i. Removal and destruction of damaged leaves and plant parts ii. Removal of ratoon crops, weeds etc. iii. Avoiding mono culture iv. Adjusting the date of sowing v. Inter- cropping vi. Need based irrigation and fertilizer application

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Chemical Control Chemicals found effective against mites are: Wettable sulphur (0.5%), Dicofol (0.04%), Dioxathion (0.1%), Replin (1.5%), malathion (400 ml/acre), tetradifon (0.03%), endosulfan (0.075%), monocrotophos (0.04%), Dimethoate (500 ml), methyl oxydemeton, Malathion (0.075%), monocrotophos (0.05%), fenthion (0.075%) and methyl oxydemeton. Biological Control Some bioagents are also reported against phytophagous mites which include i.

predatory mites (Amblyseius cucumeris, A. alstoniae, A. finlandicus, Phytoseiulus persimilis, Typhlodromus fleschneri)

ii.

coccinellid beetles (Stethorus punctum, S. punctillum, Scymnus gracilis). SLUGS AND SNAILS The members of this group belong to Phylum Mollusca. Snails differ from slugs, which show presence of spirally covered shell over their body whereas in slugs it is reduced and completely hidden under the mantle. The slugs and snails damage some flowers and shrubs located in damp and shaded places where decaying vegetation is abundant. These feed on leaves, stem or roots of plants. Common snails are Helix spp.(garden snail), Achatina fulica (Giant African snail), Hygromia, Macrochlamys, Bensomia, Opeas gracilis (green house snail) and Ariophanta. Another slug Limax sp. occurs all over India. Achatina fulica is a major (land snail) pest, measuring up to about 19.5 cm in length. Snails and slugs appear as sporadic pest in those places where shaded humid and damp conditions prevail. Habitats like wood lands, parks, gardens, hedge rows, border of marshes, ditches and canals, coastal areas may have good population of them. Extreme cold and hot weather are unfavourable for their survival. Land snails are mainly pests of vegetables, fruits, ornamental and plantation crops. About 227 host plants (belonging to 181 genera) of giant African snail have been reported. In India 66 plant species have been recorded as hosts of the snail. Out of these, 90 per cent plants are cultivated including papaya, banana, beans, chillies, lady's finger, brinjal, cole crops, cucurbits, marigold, money plant, rubber buds, coffee seedling etc. Seasonal behavior and biology: The giant African snail is nocturnal in habit and its activity is restricted generally from dusk to dawn. Maximum activity is between 9.00 p.m. to mid night. However, some can be seen even during broad day light clinging to damp walls in shady places, on hedges, stems, leaves and tops of certain plants like papaya, banana, arecanut. They avoid direct sunlight. During extreme hot and cold seasons, snails undergo aestivation, hibernation in response to unfavourable weather conditions. The snail is hermaphrodite, each individual can lay eggs. The giant African snail lays about 50200 eggs on the soil surface or a little below. The eggs are yellow in colour and hatch within 1-2 weeks and the young snails start feeding upon tender plants. The shell increases in size with age and the snail is full grown in about 2 years. The life span of A. Julica is from 2-5 years. Management: Prophylactic measures have great significance in reducing number of snails and slugs. To prevent their spread from uninfected localities, all the seedlings/saplings and other materials at the distributing as well as the receiving ends should be checked so that adult snails/slugs, their young ones or eggs are not carried along. Control operations are to be carried in two phases during inactivity (off-season) period and during activity (season) period.

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The off-season control: These are to be carried out during summer and winter when the snails are aestivating or hibernating under pieces of stones, crevices, decaying leaves and loose soil at number of places. It reduces the chances of their population build-up during rainy season. The season control: The rainy season is more favourable for snail's activity. The aestivating snails can be made active by making them wet. On attaining activity, they spread out during this period. Control during active season is difficult. Mechanical control: This is the popular, conventional and age old practice but uneconomical which implies collection and destruction of the snails and their eggs. Chemical control: A number of pesticides such as sodium arsenate, copper sulphate (45%) and metaldehyde have been used for the control of slugs and snails. Rice bran-metaldehyde bait has been found successful control of A. fulica. Use of common salt in the eastern part of India to kill A. fulica is also common. Caffeine (0.01%) acts as a repellent and toxicant against slugs and snails. Biological control: A number of natural enemies have been listed for the biological control of snails. A number of predatory snails have been introduced on Hawaii Islands and more successful were the predatory snails like Euglandina rosea (Ferussac) and Gonaxis quadrilateralis {Preston. Terrestrial pulmonates are eaten by adult frogs, lizards, snakes, birds and small mammals. It was observed that a nematode species Phasmarhabditis hermaphrodita gave positive results for the control of slugs and snails. Cultural control: Malvaceous and solanaceous crops can be grown as boundaries of two rows around the main crop. Intermixing and scattering of plantation of repe11ent varieties in cultivation are useful in reducing pest population. Marigold when planted in two rows around the plots of tomato and brinjal avoid snail infestation in these vegetable crops. Clearing of litter dumps, cutting away hedge lines and proper drainage are useful tactics for reducing slugs and snail infestation. MAJOR NON INSECT-PESTS OF AGRICULTURAL CROPS (RODENTS, BIRDS ETC.) 1. Which of the following is acute rodenticides (Single dose and quick acting)? a) Zinc phosphide b) Barium carbonate c) Warfarin d) Bromodiolone

4. The mites belonging to Eriophyoidae are popularly known as a) Gall mites b) Bud mites c) Erineum mites d) All the above

2. Which of the following is a Chronic rodenticides (Multi dose and slow acting)? a) Warfarin b) Bromodiolone c) Both a and b d) None of the above 3. Which of the following Bromodiolone poison? a) Slow acting poison b) Anticoagulant c) Multi dose poison d) All the above

refers

to

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family

5. a) b) c) d)

Scientific name of Giant African snail is Achatina fulica Opeas gracilis Helix spp. Macrochlamys indica

6. a) b) c) d)

An example of molluscicide is Metaldehyde Aluminium phosphide Aldicarp Phorate

7. Which of the following is a rodenticide of botanical origin? a) Strychnine b) Red Squill c) Both a and b d) None of the above 8. by a) b) c) d)

Wheat streak mosaic disease is transmitted

9. a) b) c) d)

Scientific name of rice field crab is Paratelphusa hydrodromus Brevipalpus californicus Achatina fulica Panonychus ulmi

b) Induce bait shyness c) Toxic to non target species and chances of secondary poisoning are more d) All the above 16. a) b) c) d)

Aceria cajani Aceria tulipae Brevipalpus phoenicis Brevipalpus lewisi

10. Which of the Bromadiolone poison? a) Multi dose b) Anticoagulant c) Acute.poison d) Mild poison

following

refers

17. Name the predatory mite feeding on phytophagous mites a) Aceria cajani b) Amblyseius fallacies c) Aceria tulipae d) Tetranychus urticae 18. Mites belonging to family Tenuipalpidae are popularly known as a) Spider mites b) Yellow mites c) Flat mite d) Broad mite

to

11. Worm-like body and two pairs of legs in all stages of development are present in mites belonging to family a) Tetranychidae b) Eriophyidae c) Tenuipalpidae d) Tarsonemidae 12. The Unique characteristic of rodents is a) Gnawing b) Chewing c) Piercing d) Rasping 13. Scientific name of Two spotted spider mite is a) Tetranychus ludeni b) Tetranychus urticae c) Oligonychus mangiferus d) Eutetranychus orientalis 14. Which of the following statement is true with respect to anticoagulants? a) They are safer than acute rodenticides b) Quick knock down effect c) Cost of operation is cheap d) All the above 15. is a)

Muranai disease on chillies is caused by Brevipalpus phoenicis Tetranychus urticae Polyphagodorsonemous latus Oligonychus oryzae

19. a) b) c) d)

Scientific name of coconut eriophyid mite is Rhynchophorus ferrugineus Oryctes rhinoceros Aceria guerreronis Opisina arenosella

20. a) b) c) d)

Example of commensal rodents are Mus musculus Rattus rattus Rattus norvegicus All the above

21. a) b) c) d)

Scientific name of Indian Mole Rat is Bandicota bengalensis Rattus meltada Mus booduga Rattus norvigicus

22. Brown color patches, longitudinal fissures and splits on outer surface of the coconut husk is due to a) Aceria guerreronis b) Aceria tulipae c) Aceria sacchari d) Aceria cajani 23. a) b) c) d)

Disadvantages of Zinc Phosphide baiting Necessity of prebaiting

209

Spider mites belong to the family Tetranychidae Eriophyidae Tenuipalpidae Tarsonemidae

24. by a) b) c) d)

Sterility mosaic of pigeonpea is transmitted 25. a) b) c) d)

Nematodes Mites White flies Aphids

210

Scientific name of Citrus flat mite is Schizotetranychus andropogoni Brevipalpus californicus Tetranychus neocaledonicus Petrobia laten


INSECT PESTS OF HOUSEHOLD, MEDICAL AND VETERINARY IMPORTANCE AND THEIR CONTROL KK Mrig Department of Entomology CCS HAU Hisar Many of the household pests are cosmopolitan in their distribution and pest status. Because wherever man went he took these pests along with his belongings. These pests have followed human civilization just as dog and cat have followed man wherever he went. Insects attack a number of ways. Some simply annoy him and some others directly injure him for his blood while a few, in the process, transmit various diseases to him. Listed here are the invertebrates known to occur regardless of pest status, in rural and urban areas. There are about 3500 species of cockroach worldwide, only about seven of which are considered major pests. The high pest status of cockroaches is due to their wide distribution, their close association with humans and their potential to carry disease. 1.

American cockroaches: Periplaneta americana (Linnaeus) (Dictyoptera: Blattidae)

American cockroach adults are 1 and 1/2 inches long wih reddish brown, fully developed wings, here is a yellowish margin on the thorax or body region behind the head. When disturbed, they may run rapidly and adults may fly. Immature cockroaches resemble adults except that they are wingless. American cockroaches generally live in moist areas, but can survive in dry areas if they have access to water. These cockroaches are common in basements, crawl spaces, cracks and crevices of porches, foundations, and walkways adjacent to buildings. Because of their fondness for sewers, large populations of American cockroaches will be seen in many cities after heavy rains or flooding. They may feed on a wide variety of plant and animal material. Damage: Both nymphs and adults feed on the sugary and starchy substances in the houses or godowns which get ruined by their excreta and offensive smell does not go even after cooking. Old damp books and leather articles are also damaged. They are also suspected of transmitting some diseases by contaminating food with germs. 2. German cockroaches: Blattella germanica (L.) They are the most common roaches found in houses and restaurants. Most cockroaches have a flattened, oval shape, spiny legs, and long, filamentous antennae. They generally develop in kitchens and bathrooms since they avoid light. During day, these roaches may be found hiding clustered behind baseboard moldings, pictures and clocks, in cracks around cabinets, closets or pantries, and in and under stoves, refrigerators and dishwashers. German roaches do not like

211

motion and usually avoid light, so if you are seeing them in the daytime while you are moving about the room, you probably have a larger population than you realize. Damage: They eat food of all kinds and may hitchhike into the house on egg cartons, soft drink cartons, sacks of potatoes or onions, used furniture or appliances, beer cases, etc. Management: (i) The cockroaches can be kept under check by observing thorough cleanliness and preventing infestation by keeping the pipelines leading to the basement and the drains sealed. (ii) The cockroaches, can be killed by spraying the room with malathion/chlorpyriphos 0.5 per cent or by repeated dustings with malathion/carbaryl 5 per cent at night in the corners on the floor along the walls.(iii) Dichlorvos 0.5 per cent spray may also be used in situations where a rapid knock-down effect is desired. 3. House fly, Musca nebulo Wiedemann (Diptera : Muscidae) The house fly is distributed all the world over and it assumes alarming proportions in hot and humid climate. ln India, the common house fly belongs to two main species, Musca vicina and M. nebulo, the latter being more common. M. domestica Linnaeus occurs only in the temperate climate. Description: It is 1/8-1/4 inch long, gray with 4 black lengthwise stripes on thorax. Abdomen is grey or yellowish with dark midline and irregular dark markings on sides. The eyes are reddish. They are found near animal manure, garbage, or exposed food. Food: Adults suck liquids containing sweet or decaying substances. Larva feeds on moist food rich in organic matter. Solid food materials are liquefied by means of regurgitated saliva. This liquefied food is then drawn up and passed into the digestive tract. Damage: The flies are a source of nuisance besides a source of contamination of food, resulting in the transmission of typhoid fever, cholera, dysentery and hence regarded as a grater threat to human health, Management: The following steps on rid homes of house flies: 

Locate and eliminate all possible breeding sites.



Move all trash receptacles as far from buildings as possible

 Dispose of all moist garbage, rotting vegetation and animal feces in bags; dispose of bags in proper receptacle.  Keep all dumpsters and garbage containers clean and dry; all dumpsters need tight fitting lids and should be emptied in a timely manner. 

Seal all possible entry points to exclude flying pests from homes and businesses.



Poison baits and sticky paper strips attract and kill a large number of flies



Fly-swatters should always be handy to knock off and kill the flies.

 The surfaces of windows and doors where the flies rest, may be smeared with 3 per cent malathion or 1.5 per cent diazinon emulsion with the help of a paint-brush. 4. Clothes moth: Two species of clothes moths viz. case-making clothes moth, Tinea pellionella and webbing clothes moth, T. bisselliella (Lepidoptera: Tiniedae) are important in homes. 212

Adults of both species are buff-colored with few distinguishing marks. They do not feed and are not attracted to light. Female moths lay from 100 to 150 small, pinhead-sized, white eggs which hatch in about five days. Full-grown larvae are about one third of an inch long. Larvae stage varies from six weeks to several years. Larvae of the case-making clothes moths live in silken cases which they drag with them. As the larva grows, so does the case, until finally the case is converted into a tough cocoon in which the pupa develops. The moth emerges in one to four weeks. Damage: Clothes moth larvae feed on wool, wool blends, feathers, fur hair, dry milk powder, leather, other animal products and sometimes on lint, dust or paper. Management  Locate the source of infestation. Look in places where clothes moth food is likely to be found .  Check corners, under furniture that has not been moved for a long time, behind baseboards, etc. 

Clean up or eliminate the source of infestation.



Clothing can be cleaned up by a professional dry cleaner to eliminate the eggs and larva.

 Vacuum cleaner is often the best extermination tool. Pay close attention to areas where lint accumulates (corners, baseboards, shelves, etc.). 

Clean or dispose of infested clothing, cloth, blankets and other fabrics.

 Store fabrics that contain wool or other animal fibers only after they have been brushed and cleaned.  Storage in tightly sealed chests or storage closets is recommended. flakes or balls can be used.

Moth crystals,

5. Bed-bug, Climex lectularius Linnaeus and C. hemipterus (Fabricius) (Hemiptera: Cimicidae) Once bed bugs invaded a home, they can be a little tough to eliminate because of their habits, size and their hardy nature. This pest is world-wide and is found in the slums and poultry sheds. The bed-bug is a small bristly brown, wingless, rather pear-shaped insect, about 13 mm long, having a distinct odour. Before a blood meal, it is flat and active, but following the meal, it turns oval and becomes sluggish. These insects hide in various areas during the day and come out at quiet times of the night to feed on human bloodThe obvious sign that a bed bug infestation is in a room is the presence of small drops of blood on sheets and pillows or pillow cases. Damage: Damage is done only at night when the bed-bug prowls about, looking, for a blood meal. The venom introduced by the bed bug bite causes itching, burning and swelling. Management: i) Vacuuming of cracks, crevices and other areas where bed bugs hide is an essential part of an integrated pest management program targeting this particular pest. ii) A combination of odorless insecticide spray and insecticide dust is needed to eliminate bed 213

bug populations with special attention given to dusting all bug hiding places. Once mattresses and box spring setups have been thoroughly cleaned and (if necessary) treated with an odorless dust, plastic covers on the mattresses will help keep bugs in as well as keep others out. iii) The bed-bugs can be controlled by treating the furniture and beds in infested houses repeatedly with malathion 1 per cent or lindane 0.1 per cent. 6. Spiders: The first detailed account of Indian spiders was provided by Pocock (1900) which lists 216 spider species under 17 families. A brief account of spiders is also provided by Vijayalakshmi and Ahimaz (1993). Tikader (1987) has listed 1066 under 43 families. Table 1 lists the number of spider species among major families found in India. Five of them namely, Lycosidae, Salticidae, Gnaphosidae, Thomisidae and Araneidae are the predominant ones. Spiders differ from an insect in that they have eight legs (rather than six) and only two body regions (instead of three). The body regions include the cephalothorax (head and legs) and the abdomen. On the head are usually six to eight eyes, often arranged in pairs. The pattern of eye arrangement is characteristic for the different spider families. Common Spiders family from India Thomisidae (Crab spiders): The body is small to moderate in size. Abdomen is somewhat large and more variable in shape than the cephalothorax. The legs are visibly spiny, especially the first two pairs which are very robust and curve and curve forwards in crab-like fashion. They body colour may be white, green or brown to match the colour of the surfaces on which the spider is most likely to be found. The usual habitats are on leaves, in flowers or on/under bark. In the last of these habitats the spider‘s surfaces are roughened to improve the camouflage. Theridiidae (Cobweb spiders/House spiders) Cobweb spiders are common inhabitants of dark corners around the home. They have a generally bulbous body and create messy webs with sticky threads. The majority of these spiders are harmless, although one group, the widow spiders in the genus Latrodectus, are potentially dangerous. Most spiders are not aggressive and bite only when trapped against the skin. If a bite is suspected or is known to have occurred, follow these first aid steps: 1. Treat the site of the bite with an antiseptic to prevent infection. 2. Apply ice to the site of the bite to reduce pain and swelling. 3. If a black widow or brown recluse spider is suspected, or if serious symptoms develop such as increasing pain or swelling, consult a physician. Controlling Spiders around the Home  Remove rocks, wood piles, compost piles, old boards, and other sheltering sites adjacent to the home. Eliminate migration of spiders into homes by filling cracks and crevices around the foundation. Make sure all screens and doors are sealed tight.  Spiders can be removed by hand (wear gloves or grasp the spider with a tissue) or with a vacuum. 214

 Residual insecticides can be used to control spiders when applied to corners and other sites where spiders tend to breed. Household insecticide products containing various pyrethroids are commonly available for this purpose and should be applied in accordance with the label‘s instructions.  Where spiders and webbing occur in nuisance numbers on the outside of buildings they can be washed off with a forceful jet of water.  Reduction of outdoor lighting, or replacing lighting with yellow or sodium vapor lights that are not attractive to insects, can limit spider web building. 7. Human louse: Pediculus humanus Linnaeus (Phthiraptera: Pediculidae) The body louse, P. humanus and the head louse, P. capitis DeGeer are almost worldwide, especially in over-crowded slum tenements, military barracks, prisons, orphanages, etc. Damage. The damage done by these insects is of three types; the stigma of having this pest which is associated with dirty slum conditions, the irritating itchy skin lesions and the transmission of certain human diseases. Management. A powder containing ma1athion 2 per cent or lindane 1 per cent is useful as a delousing treatment. For the control of infested head or body, the application of malathion 5 per cent dust two times at 10-day intervals or the use of lindane 0.2 per cent mixed with hair oil is very effective. Personal cleanliness is essential for obtaining constant relief. 8. Rat-flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae) The rat-flea or the Oriental flea is distributed throughout the world. The adult rat-flea is a hard-skinned, very spiny insect, with piercing-sucking mouthparts, concealed antennae, no wings and with very large legs for jumpin. Damage. The adult fleas, which feed only on blood, cause damage to human beings in 2 ways: first, by their piercing skin bites which cause irritating and itchy skin lesion, especially on the extremities; second, as the principal vectors in the transmission of certain important infectious diseases of man, such as the bubonic plague and murine endemic typhus. The fleas are also intermediate hosts of dog tapeworm and rodent tapeworm. Management. (i) The houses should be kept rat-free by keeping cats or by frequent poison-baiting. (ii) The houses should also be kept clean, well swept and ventilated, with occasional spraying of floors with lindane 1 per cent or malathion 0.5 per cent. 9. Mosquitoes: The species of mosquitoes which are of importance in medical entomology are those belonging to the genera Anopheles, Culex and Aedes. The various species of Anopheles transmit the malarial parasite, Plasmodium spp. from man to man. Culex quinquefasciatus is the principle intermediate host of Wuchereria bancrofti and spreads filaria in urban areas. Aedes spp. are responsible for the transmission of the dengue fever, various types of encephalitis and the yellow fever; the important species responsible for their spread are Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse). Damage: Mosquitoes (females) inflict painful bites any where on the body. The bite is 215

followed by swelling, occasional hemorrhage, reddening of skin and itching. Swelling and itching may last from a few minutes to few hours to even several days. Mosquitoes serve as cyclic or mechanical but exclusive vectors of five important human diseases, viz. malaria, filaria, yellow fever, dengue fever and viral encephalitis. Management The following strategies would go in a long way to provide protection against mosquitoes: If possible, the stagnant waters should be drained. Otherwise these should be treated with 0.025 per cent malathion emulsion  Kerosene oil may also be used for killing mosquitoes in water  Grasses and weeds around the buildings should be cut or sprayed with 1 per cent malathion after every week in the season when mosquitoes are very active  Mosquito bites can be prevented by using the mosquito nets or repellents such as citronella oil and cremes available under various trade names  The adults may be killed by using space sprays of certain proprietary products of pyretherum, synthetic pyrethroids or dich  Several insecticides such as lindane (0.5 g/m 2 ) and propoxur, fenitrothion and malathion (2g/m 2 ) have also been found effective. Suggested Readings Atwal, A.S. and G.S. Dhaliwal, 2002. Agricultural Pests of South Asia and their management. Kayani Publishers, India Gertsch, W.J. 1979. American Spiders. Van Nostrand Reinhold Co., New York. Poornima K (2001) A survey of spiders on garden crops in western ghats region, M.Sc. dissertation, Department of Applied Zoology, Mangalore University. Robinson, W.H. 1996. Urban Entomology: Insects and Mites in the Urban Environment.Chapmanand Hall, London. 1.

2.

3.

Which of . the following disease is transmitted by mosquitoes ? 4. a. Encephalitis b. Filariasis c. Yellow fever d. All the above Malaria is transmitted by (a) Male Anopheles (b) Female Aedes (c) Female Anopheles (d) Female Culex Which of the following disease is spread by house fly ? (a) Typhoid fever (b) Poliomyelitis (c) Cholera (d) All the above

Disease, transmitted by eyeflies a. Ophthalmia b. Conjunctivitis c. Both a and b d. None of the above

5.

Which of the following transmitted by human lice? a. Relapsing fever b. Epidemic typhus c. Trench fever d. All the above

6.

Which one of the following is a vector of Chagas diseases ? (a Rhodnius prolixus (b) Blatta orientalis (c) Culex pipiens

216

disease is

(d) 7.

8.

Anophelus sp.

a. b. c. d.

Dengue fever is transmitted by (a) Anopheles spp. (b) Culex spp. (c) Aedes spp. (d) All the above

10.

Leishmaniasis (Kala azar) disease caused by protozoan (Leishmania donovani) is spread by (a) Tsetse fly (b) Black fly (c) Horse fly (d) Sand fly 10.The most effective repellent of mosquitoes is (a) Oil of citronella (b) Dimethyl phthalate (c) Diethyl toluamide (DEET) (d) All the above

9.

The insecticide mosquitoes

most

effective

to

217

Deltamethrin Cypermethrin Zinc Phosphide lmidacloprid

Which of the following is. used as biological control agent in mosquito control ? (a) Fundulus sp. (b) Gambusia affinis (c) Aplocheilus panchax (d) All the above


INSECT PROTECTIVE TRANSGENIC KK Dahiya Department of Entomology CCS HAU Hisar • • • •

Indian Agriculture India An Agrarian State Agriculture continued to change Nearly 2/3 of population earn from Agriculture Amongst agricultural crops: Cotton is Life Line COTTON: A PARADISE FOR INSECT-PEST 1326 INSECT PEST SPECIES (WORLD OVER) 0230 Insect Pest species 32 countries 15-20 insect-pest species 9 countries 5-6 species are most important

IRM IN COTTON— --Cotton:

Malvaceae

Gossypium 40 species G.

arboreum ( 18%)

G.

herbaceum(12%)

Termites

Odontotermes obesus Microtermes obesi

Thrips

Thrips tabaci

Leafhopper (Jassids)

G.

hirsutum (30%)

G.

barbadens(NEGLIBLE)

Whiteflies

Hybrids(h h) (h b)

Amrasca bigutella bigutella Bemisia tabaci

Bollworms

( 32%)

Spotted bollworms

Earias insulana E. Vittella

Pink bollworms

Pectinophora gossypiella

( 8%) American bollworms

Helicoverpa armigera

----More-Problems----- Spread of disease by resistant insects  Addition of new and potentially dangerous insecticides to the environment  Greater amounts of chemicals to population already gained resistance Pesticides not only prenatal but even before conception Pesticides have been detected in fluid surrounding eggs of infertile women,  The common herbicide 2,4-D has been measured in semen  Pregnant women are most at risk Children more vulnerable  Dursban and diazinon effects on nervous systems, birth defects, immune deficiency and cancer  Symptoms: headache, nausea, diarrhea, dizziness, skin rash, asthma attack and respiratory irritation  Higher respiratory rate: Inhale airborne pesticides at a faster rate.  Children have more skin surface area for their size than adults  Pesticide concentrations: Greater in fatty tissues as their fat as a percentage of total body weight is lower  Obesity since conception due to insecticides  No sunlight, rain and soil microbes to break down indoor pesticides, persist longer than in the outdoor environment 218

 Spray-drift from nearby applications  The fetal and neonatal brain are more sensitive than the adult brain to some O P insecticides  The blood-brain barrier of infants is immature and ‘leaky,’ allowing chemicals to accumulate in the brain  Exposure during rapid cell growth when the blood-brain barrier is immature may disrupt essential elements of development. ----Problems--- Pesticides may cause birth defects, developmental delays, hyperactivity, behavioural disorders, motor dysfunction, nervous system disruption and immunotoxicity And interfere with sexual development  Health problems may be inherited by the children and become magnified with successive generations. Problems-- (Effects of Insecticide’s pollutants)  Somatic Effect:  A) Organ damage liver, kidneys, lungs, and nervous system  B) Carcinogenesis - in a wide range of tissues;  C) Teratogenesis: - damage to growing foetus resulting in gross physical abnormalities, e.g. thalidomide  D) Enzyme interactions: causing stimulation or inhibition of enzyme systems in the liver affecting its detoxification function  E) Immunotoxicity - damage to the body's immune mechanism Genetic effects:  Damage to germ cells  Manifested in future generations as physical or mental abnormalities.  Chromosomal aberrations or gene (point) mutations.  Mutations in chromosomes are drastic and expressed in next generation,  Gene mutations are normally recessive and may remain hidden for several generations Solution:

Genetic Transformation Against whom? A: Bollworms B: Tobacco caterpillar

219

Potential in IPM Biotechnology holds great potential to be included in IPM system • Reduce the selection pressure • No need of continuous monitoring of pest • Economic • Safe to non-target species WHAT IS GENETIC ENGINEERING OR RECOMBINANT DNA TECHNOLOGY • Genetic engineering or rDNA technology involves artificial transfer of genes or gene fragments • From one organism to another to produce novel traits in the recipient living organism. • The important tools used include enzymes for DNA manipulation, vectors, expression hosts and marker genes. WHAT IS A GM CROP? A GM crop contains a gene or genes of a different species artificially inserted in its genome when the inserted gene sequence comes from an unrelated plant or from a completely different species, it is also known as transgene and the resulting GM crop as a transgenic crop. WHY MAKE GM CROPS? A: Conventional plant breeding limitations • Produces a hybrid for a desired trait by cross-pollination. • GM technology is similar to conventional plant It allows the transfer of one or more genes, in a controlled and predictable way than is achievable in conventional breeding. • GM crop incorporate the desired traits more quickly and reliably than conventional methods. B: Erratic performance of Bt insecticides :  Toxin sensitivity to UV radiation, heat and desiccation  Incomplete coverage of feeding sites, or  Reduced toxicity against older larvae. C: G M Cotton overcomes these limitations  Produce its own Bt protein.  The protein is protected from rapid environmental degradation.  Plants produce the protein in tissues where larvae feed, so coverage is not an issue IS GENETIC MODIFICATION POSSIBLE?  Yes, because the genetic code is universal i.e. the DNA of all organism is made up of the same building blocks and is encoded in exactly the same way.  Transfer a copy of DNA sequence (or gene) into the cell of a different organism is possible.  Once the gene is incorporated into the genome of recipient, the resulting organism is considered to be genetically modified  And the new characteristics coded by that gene is inherited by subsequent generations.  G M involving the copying and transfer of genes from one organism to another Mode of action: • Prerequisite • The binding of toxin to midgut membrane is important step. • Presence of specific toxin-receptor binding site. Other insect species other than lepidoptera species and vertebrates lack binding site. Mode of Action of Bt Insecticidal Crystal Protein Crystal Protein solublise in highly alkaline insect mid gut Cleave in to Protoxins 133 to 138 KDa Protoxin acted upon by mid gut protease enzyme Protoxin cleaved int two halves: N terminal half 65 to 68 KDa (Toxin Protein) Toxin Protein has three domains: 1st domain for Pore formation 2nd domain for receptor binding3rd domain for protection to toxin from protease Osmotic equilibrium disturbed and cell lyse Insect paralysis and Death 220

Bacterium (Bt) Sporulation: cytoplasmic inclusion inactive protoxins) Protoxins upon feeding dissolve in the mid gut, converted to the active form (delta endotoxin) by 'trimming' with gut proteases. Activated toxin binds to insect-specific receptors of the plasma membrane of mid gut epithelial cells Create Trans membrane leakage pores that cause cell lysis and eventually death of the insect.

APPLICATIONS OF GM  INSECT RESISTANCE  HERBICIDE TOLERANCE  DISEASE RESISTANCE  PRODUCT QUALITY i. Improved flavour ii. Increased shelf life iii. High nutritional value iv. Greater processability v. Changes in composition  RESISTANCE TO ENVIRONMENTAL STRESSES  PLANT BASED PHARMACEUTICALS Advantage of Bt cotton • Reduce broad-spectrum insecticides • Lower farming risk and production costs • Better yield and profitability with early maturity • Improved safety of farm workers and neighbors • Reduced risk of wild life species • Pesticides reduction & increased natural enemies • Reduced amount of pesticides in food chain • Lower level of air pollution • Reduced run off of broad spectrum insecticides Bt provides secondary benefits 1. Eco friendly 2. User friendly 3. Farmers friendly 4. Beneficial insects increase their population. 5. Reduced fuel usage, air pollution and related waste. 6. Safety to farm workers, other birds and animals. 221

7. Cotton plants produce GREEN INSECTICIDES. Expected problem with GM Cotton

Co-evolution of plants and natural enemies Co-evolution generated biological diversity Co-evolution occurs in cycle A process analogous to co-evolution in Agriculture Example of artificial co-evolution: Hessian Fly Conventional breeding limitation Genetic transformation overcomes this limitation

Expression of Bt gene • Bt gene is driven by constitutive CaMV35s promoter. So the gene produces toxin protein in all the tissues at all the times. • Reduction in expression at later stages • Inconsistent and highly variable expression • Reduction in bio efficacy at square initiation stage `itself (Leaf Bioassay studies • Expression varies in relation to drought, stress water logging, fruit load and nitrogen rates. • Cry protein production was varying in different plant tissues. Resistance development in bollworms • Bt cotton offers limited choice in the world. • Only one gene (cry 1 Ac) has been introduced in only one species (G. hirsutum) but in different cultivars. • Bollworm community is exposed to Monotonous protein, hence, the bollworm develops resistance to cry protein. • Cross resistance to different cry proteins. Bt experiments confirmed Resistance to; • Helicoverpa virescens and H. zea (Halcomb et al., 1996, Sims et al., 1996) • Pectinophora gossypiella (Wilson et al., 1992). • Erias vittella (AICCIP, 2001-02 India). • H. armigera: Data from China, Australia and India indicated resistance to American bollworm. Key factors for resistance development in Insects • Initial frequency of resistant allele in field population • Intensity of selection in subsequent generations • Surviving the toxicant • Sustained selection pressure in GM crops • Increasing level of pest control in Bt cotton • Heterozygot has fitness advantage Mechanism of Resistance A) Genetic Basis • Initial Resistant allele frequency: (0.5) complete control failure expected • Resistance: Dominant or Recessive Vertical or Horizontal • Genetic variance: Larger, more genetically varied populations develop resistance more quickly 222

• Survival rate of RR, RS and SS genotype • Unidirectional Selection • Strong selection pressure: for the development of resistance to the toxins • Additive genetic variance • Mode of inheritance • Factors influencing Hardy-Weinberg equilibrium Other Factors: More persistent insecticides more resistance development  Frequent application of non-persistent insecticides has the same effect  Mode of action of new and old insecticide if similar insects quickto develop resistance to the new toxin  Species with higher reproductive rates & shorter generation times  Insect populations with little immigration into the gene pool of new,non-exposed susceptible individuals also develop resistance more readily  Relative host preference  Natural survival  Insecticidal survival  Random mating  Mating synchrony between resistant and susceptible genotype  Accessible abundance of non Bt hosts  Crop maturation period different in Bt & Non Bt  Mating asynchrony in Bt & Non Bt B)Biochemical • Change in the membrane receptors where activated Bt toxins bind • Reduced toxin binding sites • Decreased activation of the toxin, • Absence of a major gut proteinase associated with the proteolytic cleavage and activation of Bt protoxins Resistant factors in Insects Fitness advantage: • Selection pressure results in increased fitness for heterozygote in relation to homozygote susceptible thus frequency of alleles for resistance build up • RR(Susceptible) RS(Fitness increased) SS (Resistant) • Alleles of genes conferring adaptive advantage always present in the population or • May appear by mutation • One gene in many crops against the same pest Consequences of GM Cotton Gene flow • Transgenic to wild relatives, selective advantage to wild plants • Transgenic to herbicide tolerance could produce new noxious species (Super weeds) • Possibility of development of resistance to GM toxin Bt Resistance Management Strategies • Genetic variation • Geneic Variation • Gene stacking/pyramiding • Combination of more than one strategy • High/ultra high dose • Avoid Bt based bio-pesticides • Spatial and Temporal refugia • Avoid excessive vegetative growth • Irrigated Bt cotton less effective than dry land Bt cotton • Effectiveness of Refuge low initial resistant allele 223

• Matting between susceptible insect from refuge • Hand picking of larvae in Bt cotton • Use trap crops Resistance Development in Insects slower If • Survival of SS genotypes was higher • Survival of RR genotypes was lesser on Bt cotton • Proportion of Bt cotton area less Resistance Management Strategies  Gene deployment  Gene Pyramiding  Destruction of Carry over population  Use of Economic Threshold • Refugia • Tissue specific expression • Temporal regulation of toxin as an insect inducible response • Regulation of expression Use promoter (LEA Promoter (Late Embryogenesis Abundant) Bt. Resistance management • Protein Pyramiding – Multiple cry genes – Cry plus other insecticidal genes (P. lilminescence). • Protein Synthesis – Tissue specific expression, inducible expression – High/ultra high doses • Field Tactics – Planting refuges – Cry gene crop rotation – Variable fitness cost – Non recessive fitness cost – High level of incomplete resistance – Recessive inheritance of resistance – Matting between susceptible insect from refuge Management of Bt Resistance Biotechnology • Incorporate minimum of two factors as probability of mutation at multi loci is less than at single locus. • Utilization of cultivars/hybrids composed of blends (with or without resistant trait). Disadvantage of Bt cotton • Target organism and not all Lepidoptoran • Sucking pests not controlled • Bt cotton does not control large larvae • Bt cotton does not control Spodoptera larvae • More water and fertilizer requirement Hurdles in transgenic development • Expression of gene Cry gene highly expressed in Natural host (Bt) But poorly expressed in plants. Improvement of expression SWOT analysis of Bt cotton in India Strengths : • Highest cotton area in the world. • Cultivation of hybrids on commercial scales. • Seed replacement rate in hybrids is 100 per cent. 224

• Lower seed rate in South and Central India. • All four cultivate species. • Development of Eco-specific cultivars. • Strong cotton breeding network both diploid and tetraploid cotton. Weakness : • In North India varieties are grown so SRR is very low. • Seed rate is high hence, accomodation of hybrids has been difficult till today. • Leaf curl virus and other sucking pests are as major as bollworms. • Too many cultivars/hybrids (Nearing to 140 excluding private sector research hybrids). Opportunities : • Transformation in diploid cultivated cotton • Genetic transformation for sucking pests • Largest cotton seed industry • Hybrids – multiple gene constructs Threats : • Unwanted spread of seeds leads to seed related problems. • Use of plant refugia cannot be ensured. • Minor pests may become major. • Resistance development in bollworms. • Change in the feeding time of bollworm may also expected. • Start of Bt gene war. Prerequisite for effective Helicoverpa management • Resistant allele must be recessive • Recessive allele in field population should be rare • High dose expression in Bt genotypes • Helicoverpa in Indian conditions is • Resistant allele is semi dominant • No High dose expression in Bt genotypes (Hybrids hemizygous ) Future thrust Areas • Creation of Bt Varities • Tissue specific expression • Introduction of gene in chloroplast genome

225

NEMATOLOGY

226


NEMATODE PEST MANAGEMENT PRACTICES RS Kanwar Department of Nematology CCS HAU HIsar In present day agricultural, plant parasitic nematodes have been recognized as a major constraint in crop production. Nematologists have made sustained efforts to develop suitable management practices for these crop pests. The choice of these methods, however, depends on the type of crop, nematode problem involved, and resources available with the growers etc. A brief account of these management practices is given here under. I) Cultural method: It includes methods of crop husbandry for the management of nematodes. Cultural methods includes mainly crop rotation, adjustment of sowing/planting time, use of organic amendments, fallowing, flooding, use of healthy planting material, trap crops, antagonistic plants. i) Crop rotation: In rotation, non-host crops are used to keep the nematode population below economic threshold level. Length of rotation depends upon the nematode species. Potato cyst nematode (Globodera spp.) can be controlled by growing crops like cabbage, cauliflower, peas, maize, beans, strawberry etc., for three years. Likewise, the cereal cyst nematode, Heterodera avenae can be controlled by growing mustard, carrot, peas, gram, fenugreek etc. for 2-3 years. Root knot nematode (Meloidogyne spp.) a polyphagous pest can also be managed by non host crops like crucifers, cluster bean, resistant vars. of chillies and tomatoes, etc. Use of antagonistic crops like marigold (Tagetes spp.) and Crotalaria are more effective as rotational crops in reducing nematode populations. ii) Planting time adjustment: By adjusting time of sowing/planting, nematode damage can be reduced to some crops e.g. in wheat, early sowing is recommended to reduce the damage by H. avenae. Similarly, late sowing of gram helps in lowering the crop damage by Meloidogyne spp. Early potatoes and beets grow in soils too cold for cyst nematode activity. By the time the soil warms sufficiently for nematode to become active, the plants are mature enough to with stand attack of larvae. Thus, a good crop is obtained. iii) Fallowing: In absence of host plants, nematodes are starved to death. For practical purposes, fallowing is not economically feasible. Susceptible weeds, which may act as alternate or collateral hosts should not be allowed to grow during fallow period. iv) Flooding: This method has been found effective against root-knot and stunt nematodes on vegetable crops. Flooding kills the nematodes by asphyxiation. In flooded soils, chemicals like H2S, NH3, butyric acid and propionic acid are produced which are harmful to nematodes. v) Organic amendments: Addition of organic amendments such as oil seed cakes, compost, F.Y.M., phytotherapeutic substances have been found effective in decreasing nematode 227

population and producing good crop. Organic amendments improve soil texture and provide ample nutrition and thereby tolerance to nematodes. Organic matter reduces nematode population by producing toxic substances like H2S, and by promoting antagonistic organisms. vi) Healthy planting material: Nematodes spread along with seed or other propagating material. Citrus nematode, root knot nematode are carried in earth balls with seedlings; wheat seed gall nematode (Anguina tritici) and rice white tip nematode (Aphelenchoides besseyi) with seeds, potato cyst nematode with potato tubers, burrowing nematode (Radopholus similis) in banana with infected rhizomes. These nematodes can be controlled by using healthy seeds and other planting material. vii) Trap crops: These are the crops which do not allow the nematode to complete life cycle after penetration or the nematode is not allowed to complete life cycle as crop is destroyed before it completes life cycle. Meloidogyne spp. can not develop to adulthood after penetration in Crotalaria. Similarly, winter maize and oats act as trap crops for Heterodea avenae as nematode larvae enter but fail to develop or reproduce on them. viii) Antagonistic plants: Some antagonistic plants produce nematotoxic compounds. These chemicals adversely affect the nematode populations. Mustard produces a toxic substance allylisothiocyanate. A chemical, pyrocatechol accumulates in high concentration in roots of Pangola grass (Eragrostis curvula) which acts as a potent nematicide against several species of Meliodogyne. In Asparagus officinalis, a glycoside (asparaguisic acid) is found which reduced population of Trichodorus christiei and several other nematodes. α-terthienyl present in roots of Tagetes spp. reduces the population of root-knot, root lesion and stunt nematode. Crotalaria spectabilis adversely affects Meloidogyne sp. and Xiphinema americanum. ix) Sanitation: Plant roots and other debris harbour very high nematode inoculum. Thus, removal and destruction of them from field is helpful in lowering down the nematode population. Burning of stubbles of rice controls Ufra disease of rice caused by Ditylenchus angustus. Sanitation also controls mushroom nematodes by preventing their entry in the mushroom house. 2. Physical control: Physical control of nematodes includes cleaning of seeds by washing, sieving etc., and use of heat to treat soil or propagating material. Soil solarization and hot water treatment are widely used practices for nematode control. Citrus rooted cuttings, banana suckers, rice seeds and strawberry runners are made free from citrus nematode, burrowing nematode, white tip nematode and foliar nematode by treating the material with hot water at 45°C for 25 min., 50°C for 10 min, 52°C for 10 min and 46°C for 10 min., respectively. The temperature should be selected in such a way that it kills the nematode pest but does not affect the plants. 3. Biological control: A large number of microflora and fauna cohabiting with nematodes in soil has been known to parasitize and predate upon nematodes. Parasitic and predacious fungi, bacteria, nematophagous mites, predatory nematodes are some important biocontrol agents of nematodes. Besides these, predatory protozoans, tardigrades, turbellarians, collemboles, enchytraeids and parasitic protozoa, rickettsias and viruses have been reported to affect nematodes population. Paecilomyces lilacinus (an egg parasitic fungus) and Paestenria penetrans (a spore forming bacterium) are potential bio-control agents of root-knot nematodes. They have been found effective in controlling this nematode under field conditions also. Predacious fungi, produces sticky network (e.g. Arthrobotrys sp.), sticky knobs (e.g. Monacrosporium 228

ellipsospora), constricting rings (e.g. Dactylaria brochopaga and Monacrosporium bembicodes) and non-constructing rigs (e.g. Dactylaria candida). Zoospore forming, endoparasitic fungi like catenaria spp. penetrate the cuticle of nematode by producing a germ tube. Some plant growth promoting rhizobacteria (PGPR) such as Azotobacter Chroococcum, Gluconoacetobacter diazotrophicus, Pseudomonas fluorescens, and P. putida have nematotoxic properties. Arbuscular mycorrhizal fungi like Glomus mossae and G. fasciculatum have shown promising results against root-knot and cyst nematodes. They affect the nematode penetration, development and reproduction. Predatory nematodes belonging to Genera Monochus, Mononchoides, Butlerius, Anatonchus, Diplogaster, Fictor and Tripyla (with open stoma), and Seinura (stylet bearing) have been reported to kill nematodes and reduce their populations in laboratory and pot/field conditions. 4. Plant resistance : Resistance is the ability of plant to resist or withstand the attack of pest or pathogen. It is an effective, economical and environmentally safe method of nematode management. It helps the growers to manage nematodes without increasing the cost of production. Resistance may be pre-infectional or post infectional. Availability of resistance is more common in specialized host-parasitic reactions such as the sedentary endo and semi-endo parasites. In developing nematode resistant plants, several steps are involved as follows: 1.

Correct identification of nematode spp. and race.

2. Techniques for evaluation of resistance must be devised to designate a plant resistant, tolerant or immune. 3.

Inheritance of resistance should be studied so that breeding programme may be initiated.

4. Crosses and back crosses are made to develop agronomically desirable nematoderesistant variety. 5. Testing of resistant var. under field conditions, in different soil types and environments before its commercial cultivation. In India, some nematode-resistant vars. available in different crops are: -

BH 75, BH 393, RD 2035, RD 2508, C-164, Raj Kiran of barley and Raj MR-1 wheat against H. avenae.

nematode.

Kufri Swarna and Kufri Thenmalai of Potato against Globodera spp. potato cyst

Hisar Lalit, PNR 7, SL-120 of tomato and Pusa Jawla chillies against root-knot nematode, Meloidogyme spp. nematode

Pant-10 and UPAS-120 pigeon pea, Sel. 30 peas and GH 3 castor against reniform

-

Pleurotus sajor caju, (oyster mushroom) against mushroom nematodes.

5. Chemical control : Chemical control is used when other methods of nematode control do not provide sufficient protection to crops. In high value crops, this method is desirable to get good 229

returns. Primary advantage of chemical control over other methods is that it gives spectacular results in short time and reduces nematode population to low levels. Mathews (1919) discovered nematicidal properties of chloropicrin (tear gas) which gave 99-100% kill of nematodes and later on, it was used for this purpose. Carter (1943) used D-D mixture (dichloropropenedichloropropane) at Pineapple Research Institute, Hawai and Chrstie used EDB (ethylene dibromide) in Florida to control nematodes. These two chemicals marked the beginning of new era in nematode control. Chemical nematicides broadly can be grouped in two categories – Fumigants and Nonfumigants. Fumigants: They are highly volatile, halogenated hydrocarbons. They turn into gaseous form when applied in soil, diffuse through soil pores and are toxic to nematodes e.g. DD, EDB, MBr, DBCP etc. Another group of fumigant nematicides, which release methyl isothiocynate (MIT), e.g. dazomet, metham sodium etc. was developed later on. Fumigants have some limitations such as: They are highly volatile, phytotoxic, needs waiting period of 3-5 weeks so can be used only as pre- plant application, some needs plastic covering to prevent escape. DBCP was found carcinogenic, leaves bromine residue in fruits and hence it was banned. Non fumigants: According to their chemical group, these are classified into organophoshates and carbamates. Ethorophos, fensulfothion, phenamiphos, phorate, thionazin are examples of organophosphates and aldicarb, carbofuran, oxamyl are carbamates. These chemicals inhibit the enzyme acetyl cholinesterase and thus interfere with normal functioning of nervous system resulting in loss of muscular coordination, convulsion and ultimate death. Advantages of non-fumigant nematicides 

They are non-volatile



Effective against insects like aphids, white grubs etc.



Easy to handle and apply



Effective at lower doses



Less phytotoxic and can be used in standing crop.



Systemic and slow release in action



No waiting period required

Economic use of nematicides To reduce the cost of nematicidal application, following practices can be adopted. 

Bare root dip treatment in systemic nematicides (oxamyl, thionazin) in transplanted crops



Seed treatment (coating/dipping) in bold seeded crops



Nursery bed treatment.



Row and spot treatment in widely spaced crops.

6. Regulatory control: Regulatory control of plant nematodes is the legal enforcement of measures to prevent spread and multiplication to intolerable level. Principle involved in enacting 230

quarantines is exclusion of nematode from entering into new area. Quarantines are traditionally used to restrict the movement of infected plant materials and contaminated soil into a state or country. Quarantine can be external (international) or internal (domestic). In India DIP Act, 1914 and the rules framed there under "Rules for regulating the import of plants etc. into India" restricts the movement of plant material to prevent the introduction into and the transport from one state to another in India of any insect, fungus or other pest which is or may be destructive to crops. The rules permit the Plant Protection Advisor to the Government of India or any officer authorized by him to undertake inspection and treatments. Specific regulations for potato cyst (Globodera spp.), red ring of coconut (Rhadinaphelenchus cocophilus) and pine wood nematode (Bursaaphelenchus xylophilus) have been made. Domestic quarantines have been imposed to restrict the movement of potato to prevent the spread of potato cyst nematode from Tamil Nadu (Nilgiri hills) to other parts of country.Govt. of India's Plant Quarantine order 2003 (Regulation of Import into India) and its subsequent amendments regulate import and prohibition of import plants and plant products into India. In schedule IV, V & VI of this order plants/planting material and countries prohibited are listed and several nematode spp. have been included in schedule VI. 7. Integrated management No individual method is perfect in controlling nematodes under all situations. However, there is great scope of combining two or more methods in a complimentary manner. The best strategy for nematode management would be integrated pest management techniques. The aim of an integrated approach should be : i) to use several compatible methods together, ii) to maximize natural environmental resistance to plant nematodes, iii) to apply specific and drastic control measures only when necessary, and iv) to maximize profit to the grower with location and resource specific recommendations. Barker and Lucas (1984) identified five components of integrated nematode management in tobacco, viz., (i) destruction of roots debries of previous crop (ii) nematode free transplants, (iii) resistant cultivars (iv) crop rotation and (v) effective chemical treatment. In India, several attempts have been done to integrate methods for nematode management. Root-Knot nematode in vegetable crops and cereal cyst nematode in wheat can be managed by combining suitable control methods. Seed treatment, solar drying of soil, organic amendment or resistant variety can be possible approaches for transplanted crops. Likewise, rotation with non-host or resistant var., deep summer ploughing, removal of infected crop residues, organic amendments, proper nutrition, seed treatment of direct sown crops, spot or row treatment with nematicides and thorough weed control are some feasible practices at field stage. Merits and demerits of major nematode control methods Merits A. CULTURAL Low cost, minimum effect on non-target organisms, no toxicity or residue problems, no special technique required (a) Fallowing

Demerits Not always applicable less efficient, mainly preventive, forward planning required, may interfere with normal cultural practices. Death due to starvation and Thorough weed control desiccation necessary, some nematode stages become adapted through quiescence, not very 231

(b) Flooding

Death due to starvation, asphyxiation and microbial decomposition products due to anaerobic conditions

(c) Summer ploughing

Exposure of nematodes to solar heat and desiccation, kills other pests and weeds. Feasible between two main crops. No additional cost required, no loss of cropping period

(d) Time of planting

(e) Manuring organic amendments

Improve host tolerance and yield

(f) Antagonistic crops

Nematodes killed by action of root exudates,

(g) Trap crops

Nematodes attracted and held in roots, not allowed to mature.

(h) Crop rotation

No loss of cropping period valuable crop obtained, no erosion.

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effective in humid areas, may impair soil structure or encourage erosion, loss of cropping period, not fit for multi-cropping system. Long periods required, may alter soil structure and chemical nature, may cause leaching of nutrients, possibility of introducing new pests and bacterial diseases etc. not applicable to dry areas, loss of cropping period. May cause wind erosion and dispersal especially in light soils, not possible in wet, humid and temperate environment. Selection of cultivar for late or early sowing necessary, elaborate knowledge of population dynamics necessary, useful only in areas with drastic seasonal changes. Additional cost involved, may leave higher final nematode populations. Poor economic value, large scale production not feasible, loss of cropping period, may be effective against a specific nematode only Cost of cultivation and some loss of cropping period involved. Trap crops allowing maturity if not destroyed timely leave high nematode population, not effective for ectoparasites. Difficulty in finding agronomically suitable nonhost economical and acceptable to the farmer. May increase some nematodes, elaborate knowledge of population dynamics and host

reaction necessary. Slow development of resistant varieties, may not be agronomically and economically acceptable.

B. PLANT RESISTANCE

Low cost, no adverse effect on natural enemies or nontarget organisms, no toxicity or residue problems, no special skill necessary at farmer's level, no damage even in presence of high nematode population. (a) Resistant varieties No increase in nematode Possibility of break-down of population. resistance or evolution of resistance breaking biotypes. (b) Tolerant No possibility of break-down Very high residual population crops/ varieties of tolerance for the subsequent crop. C. Relatively low cost, Degree of control usually BIOLOGICA permanent (except insufficient, research costs L (Parasites, predators and sometimes for pathogens), high; pathogen required to be pathogens) not harmful to non-target cultured and released organisms, no toxicity or repeatedly involving recurring residue hazards. costs, high population of parasites and predators difficult to establish. D. PHYSICAL Low cost, minimal effect on Removal of all infested crop (a) Sanitation non-target organisms, no residues difficult and and destruction of infested toxicity or residue hazards, expensive, free population in crop residues relatively quick in reducing soil not affected, organic infestation level, no special matter in soil reduced. skills involved. (b) Solar heat Minimum costs of exposure Effective only in summer of soil or infested tissues to months in tropics and sun, moderate effect on non- subtropics, cost of turning soil target organisms, helpful in and possibility of wind weed control, ideal for erosion, many parasites, tropical areas predators and pathogens may also be killed. (c) Steam Better penetration, high Loss of non-target organisms, latent heat, almost complete high cost, adverse effect on elimination of nematodes, soil structure, not practicable other pathogens and weeds, on large scale, can be used ideal for small scale use such only as pre-plant treatment. as pot soil, greenhouse and mushroom beds. (d) Hot water Easier to use, suitable for Risk of losing viability if disinfecting seed and other temperature and time not planting seed and other properly controlled. planting material in dormant 233

E. CHEMICALS

(a) Fumigants (Halogenated hydrocarbons)

state, efficiency improved by pre-treatment soaking. Quick in action, effective against most nematodes, sometimes curative, can be applied when and where required, high efficiency visible crop improvement, ideal for demonstration of crop losses.

Quick in action, penetration in soil

better

(b) NonEasy to handle as granular fumigants (Carbamates and formulations, relatively organophosphates) smaller quantities required, low phytotoxicity, may be applied to standing crop and planting material, systemic action some show basipetal movement and hence used as sprays in low concentrations (c) Specificity of action, Antimetaboli required in very small tes and steroids quantities, applied to standing young crop, no toxicity or residue hazards, no effect on non-target organisms Modified after Sethi and Guar (1986)

High cost, non-availability, may harm natural enemies and non-target organisms, residue problems, control not permanent, may last only a single season high risk to operator, phytotoxicity, risk of evolution of resistance in nematode on repeated use, large quantities required for soil treatments. Elaborate equipment and special skill required, gas proof cover required in some cases, not possible to apply in standing crop, only preventive in most cases, may cause air and water pollution. High cost, high mammalian toxicity and residue problem in some cases, may cause water pollution effective for a single cropping season.

Improper use may harm crop, non-availability and high costs, nematodes likely to readapt or develop resistance on repeated use.

Objective questions of nematology on nematode management 1.In India , domestic quarantine is enforced against 3. Root exudates of Tagetes spp. have nematotoxic a. Heterodera avenae compound b. Radopholus similis a. α- terthinyl c. Globodera rostochiensis b. allyl isothiocynate d. Aphelenchoides besseyi c.cajenol Q2.crop rotation is more successful in d. asparaguisic acid a. Host specific nematodes 4.Carbofuran belongs to b. Polyphagus nematodes a. Fumigant nematicides c. Foliar nematodes b. MIT liberators d. Endoparasitic nematodes c. Organophosphates

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d. Carbamates 5.BH 75 is a nematode resistant variety of a. Wheat b. Barley c. Tomato d. Chickpea 6. Organic amendments control nematodes by a. Producing toxic substances b. Increasing antagonists c. Increasing crop tolerance d. All above 7. Which of the following is an egg parasite of root knot nematode a. Pasteuria penetrans b. Paecilomyces lilacinus c. Dactylaria candida d. Catenaria spp. 8.first chemical used as nematicide was a. DBCP b. DD c. EDB d. MBr 9. Pasteuria penetrans is a a. Fungal parasite of nematodes b. Plant pathogenic bacterium c. Bacterial parasite of nematodes d. Protozoa 10.EDB belongs to which group of nematicides a. Fumigant

b. Non fumigant c. Organophosphates d. Carbamates 11. Hisar Lalit is a nematode resistant variety of a.Potato b.red gram c. chillies d.tomato 12. Which predatory nematode has stylet a. Fictor spp. b. Seinura spp. c. Tripyla spp. d. Mononchoides spp. 13. Which nematode disease can be effectively controlled by hot water treatment of seed a.Ufra of rice b. white tip of rice c. root knot of rice d. molya of wheat 14. Raj MR1 is a nematode resistant variety of a.maize b.barley c. wheat d.tobcco 15. UPAS variety of pigeon pea is resistant to a.root knot nematode b. pigeon pea cyst nematode c. reniform nematode d. all above

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Manual on ICAR-JRF (PGS) in Agriculture – Entomology and Nematology Eds SS Yadav, KS Bangarwa, Surender S Dhankhar and RK Pannu CCS HAU, Hisar 2014, pp 236-243

ENTOMOPATHOGENIC NEMATODES Kumkum Walia Department of Nematology CCS HAU Hisar Nematodes have different kinds of association with insects. This includes pathogens: Steinernema, Heterorhabditis, Neosteinernema; Insect associates: Laimaphelenchus Bursaphelenchus and Rhadinahelenchus: parasites of insects; mermithids and sphaerulariids: fungivores; aphelenchids: microbivores; rhabditids and predators; monochids, dorylaimids, nygolaimids and diplogasterids. Of these associations, pathogens or the entomopathogenic nematodes are beneficial nematodes which kill nematodes within 24-72h. These belong to class Secernentea, order Rhabditida and families Steinernematidae and Heterorhabditidae (Genera Steinernema, Neosteinernema and Heterorhabditis). These nematodes are efficient bio control agents and are mutualistically associated with bacteria, Photorhabdus (in Heterorhabditidae) and Xenorhabdus (in Steinernematidae). Family Steinernematidae Morphology: Infective Juveniles (IJs): 3rd stage juveniles are called infective juveniles. Rhabditoid oesophagus. Non-feeding stage. So, stoma, oesophagus and intestine collapsed. Mouth and anus both closed. ‘Dauer larva’ is a resistant stage. Cuticle is annulated. Lateral field with 6-8 ridges. Specialised bacterial pouch (ventriculum) located at the end of basal bulb.

Infective Juveniles

(IJs)

Excretory pore is distinct, anterior to nerve ring. Tail is conoid or filiform, with variable hyaline portion. Phasmids are present- prominent or inconspicuous. 236

Adults: Two types of adults • 1st generation female and males • 2nd generation female and males Females are larger than males and 1st generation adults are bigger in size than 2nd generation adults. Identification is mainly based on morphometrics of IJs and 1st generation males. Other generation adults supplement the information on the species description. Adults have truncate to slightly rounded head. Six fused lips with distinct tips and one labial papilla each. Four cephalic papillae present. Amphids are small. Stoma reduced, short and wide with inconspicuous sclerotised walls. Oesophagus rhabditoid, set off from intestine. Nerve ring usually surrounding isthmus or anterior part of basal bulb. Excretory pore opening is distinct Females are with paired and opposed ovaries. Vagina is short and muscular. Vulva is located near middle of body with or without protruding lips. Epiptygma may be present or absent.

Females- Tail, Head & Epiptygma Males are monorchic, testis is reflexed. Spicules are paired and symmetrical. Gubernaculum is present. One single mid ventral and 10-28 pairs of genital papillae are present of which more than half are precloacal in position. Bursa is absent. Tail is rounded, digitated or mucronated .

Male Tails Showing Papillae (SEM Photographs)

Family Heterorhaditidae Morphological variations from Steinernema : 2nd stage cuticle is tightly adhered to 3rdstage IJs and is not lost easily. Hence IJs should be more resistant. IJs have a tooth like structure in the head region which helps in penetration through intersegmental membranes. Excretory pore located at base of oesophageal bulb. Tail is long. The bacterium is lodged in the anterior portion of intestine and not in pouch. Bacterium is 237

Photorhabdus sp. Which imparts reddish brown colour to the cadavers and also luminescence when observed in dark. Males are with bursa and encountered only in second generation. In first generation hermaphrodites are present instead of females and males.

Life Cycle: The infective stage is third stage juveniles which remain in the soil in the dormant state in the absence of the host. The infective juveniles (IJ) can locate their insect host by moving towards it by some chemical cues emanating from the insects. IJs enter through natural openings i.e., mouth anus or spiracles. In heterorhabditids IJs can penetrate through inter-segmental area too with the help of horn like projections present at the anterior end. Those entering through anus or mouth penetrate through gut wall to reach the haemocoel. The IJs feed on haemolymph and in turn inoculate the bacterium carried by them. The bacterium multiplies on haemolymph and produces certain toxins which cause septicaemia in insects and the host dies within 24-72h. The bacterium also converts the inner contents of insects into a gummy nutrient rich medium suitable for nematode development and multiplication. Once respective bacterium develops, no other microorganism can develop inside the host cadaver. It is an example of essential mutualistic association since bacterium is not found in the soil and can be carried to insect host by the IJs only and IJs multiply only in presence of the bacterium. Steinernematid IJs reproduce by amphimixis in both the generation while in Heterorhabditids reproduction is by hermaphrodites in first generation whereas males and females both are produced in further generations. Normally 2-3 generations are completed depending on availability of food source. During depleting food source the juveniles incorporate bacterium in their pouch/ intestine and undergo dormant stage under unfavourable conditions. Millions of IJs are produced by Steinernema after a week whereas Heterorhabditis may take upto 10 days but in former case minimum two IJs of opposite sex must penetrate to initate the multiplication while a single IJ in Heterorhabditis will produce lakhs of IJs of next generation.

Life cycle of Steinernema and Heterorhabditis

Host finding strategies: Two strategies: a) Cruising- Cruisers actively move in the soil and can reach their host.

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b) Ambushing- Ambushers stand on their tails on soil particles and infect the host in their way.

which comes

Some of the species employ both the strategies. The Bacterial symbionts: The two genera Xenorhabdus (in Steinernema) and Photorhabdus (in Heterorhabditis) belong to family Enterobacteriaceae. These are motile gram-negative which do not reduce nitrate and ferment only a limited number of carbohydrates and are Inoculated in haemolymph of insect by IJs of entomopathogenic nematodes. Proliferate and produce a wide range of toxins and hydrolytic exo-enzymes which cause death of host. Bacterium leads to bioconversion of insect larva in to a nutrient rich medium ideal for nematode growth and reproduction. The nematodes develop to infective juveniles after nutrient supply is depleted. Then incorporate bacterium in intestinal vesicle/ anterior part of the intestine. The bacterium benefits from this interaction by being transported to the nutrient rich haemolymph of the insect. The nematodes take advantage of the pathogenic potential of the bacteria to help kill the insect host. The bacteria also supply the nutrient base for the growth and development of the nematode. Bacteria suppress contamination of the insect cadaver by soil micro-organisms. Phases of Bacterium: Two phases

i) Primary or Phase I ii) Secondary or Phase II

Phase I coloniesPhase II colonies-

isolated from natural infections Change to phase II on storage

Colours on Mc Conkey’s Agar Phase I- reddish or reddish brown Phase II- off white, grey or light yellow Colours on NBTA or T7-TTC agar Phase I- greenish to blue Phase II- reddish Host specificity of bacteria: Nematode species Bacterial species S. longicaudum X. beddingii S. affine, S. feltiae S. kraussei S. intermedium X. bovienii S. carpocapsae X. nematophila S. kushidai X. japonica S. riobrave X. cabanillasii S. glaseri, S. cubanum X. poinarii Nematode species H. bacteriophora H. Bacteriophora (HP88)

Bacterial species P. luminescens subs luminescens P. luminescens subs laumondii 239

H. Bacteriophora (Turkey) kayaii H. indica

P. luminescens subs

Heterorhabditis sp.

P. luminescens subs akhurstii P. symbiotica subs.

australis H. zealandica, H.megidis

P. temperata

Bacteria isolated from “cold adapted” species S. feltiae and H. megidis are adapted to lower temperature while those from tropical and sub-tropical area grow well at high temperature. Once inside the insect haemolymph the bacterium proliferates, produces certain antibiotics which inhibit the growth of other microorganisms. Bacterial strain can be easily isolated from such host cadavers. This isolated bacterial strain is multiplied on nutrient broth/agar and utilised in mass culturing of EPNs. Isolation Techniques:  Direct examination of insect cadavers- very difficult to collect dead insects naturally infested.  Cobb’s Sieving method- routine nematode extraction method does isolate IJs but difficult to identify by a non taxonomist  Insect Trap method (Bedding & Akhurst, 1975): Most commonly used and efficient method. i. Place 5-10 late instar larvae of Galleria/Corcyra at the bottom of a container. ii. Add 200-300 cc soil depending on the size of the container. iii. Cover with lid and keep the containers at 15-30° C or at lower temperature if the soil sample is collected from temperate zone. iv. Remove dead larvae after every 24 h for 3-4 days. v. Rinse cadavers in sterile water – 4% NaOCl – sterile water to get rid of soil mites. vi. Place the larvae on dry filter paper lined in a Petri-dish. Cover the Petri-dish. vii. Place the Petri-dishes in an incubator enclosed in polythene bags for 2-3/5-7 days for Steinernema and Heterorhabditits, respectively Extraction of IJs from Cadavers: White Trap method (White, 1927)  Place a small watch glass upside down in a Petri-dish.  Place a moistened filter paper cut to the size of watch glass.  Arrange insect cadavers on filter paper.  Cover the Petri-dishes, seal with parafilm and store in incubator for 3-5/7-10 days enclosing in polythene bags to conserve moisture. Storage of IJs  Can be stored at 4-15 C for several months.  Surface sterilize with 0.1% Hyamine for 5 min and wash with sterile water thoroughly.  IJs in sterile water can be stored in tissue culture flasks/Erlenmeyer’s flasks.  Aeration is required intermittently.  Add a drop of Triton X-100 and a few drops of Sodium bicarbonate to avoid clumping and adherence to walls of the container.

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Mass Production of EPNs: Two ways: i) In vivo ii) In vitro In Vivo Production Most suceptible host is Galleria mellonella . All EPNs except S. kushidai and S.scapterici can be cultured on wax moth larvae. Moth larvae are large in size and easily cultured on natural / artificial diet. For host specific species, the same host is used on which it is originally isolated. EPNs are multiplied by ‘filter paper method. In this method, nematodes (20 IJs per insect) are inoculated on a filter paper fitted in the lid of the Petri dish and the larvae of Galleria / Corcyra are released. Incubated for 3-5 days and then transferred on a ‘White Trap’ for recovery of juveniles. For white trap one can use a small watch glass fitted with a wet filter paper cut to size or a small Perti dish whose one end touches the wall of larger dish forming a thin film of water at the point of contact and IJs are slowly transferred to water in larger dish. The insect larvae infected with nematodes will be flaccid, greyish or reddish in colour due to Steinernema and Heterorhabditis infection, respectively and do not smell putrid. The colour of the infected larvae is due to infection of particular bacterium inside. Photorhabdus infection also imparts luminescence to infected larvae. Good for small scale production for use in lab. and green house experiments. It is not viable for commercial production since it is labour intensive. However, a method called LOTEK (Low cost technology) method was devised by Gaugler to increase the harvest of the IJs. Harvesting, separation, clean up processes all are automated to a)

reduce labour cost

b)

Increase scalability

In Vitro culturing: Isolation of symbiotic bacteria; Bacteria can be isolated from IJs or from insect haemolymph infected with nematode. Bacterial growth media used are NBTA, MacConkey agar, Nutrient agar. Colony colour determines the bacterial phase. Primary phase: Red, bright pink, red brown while Sec. phase: Light yellow, brown, grey. Only primary phase colonies are used for culturing nematodes. Isolated bacterium is multiplied on liquid medium 24h before inoculation to medium for nematode culturing. Two Types of Cultures: Solid culture: Animal or vegetable protein based media are used. The medium is impregnated on to polyether-polyurethane sponge (an inert medium carrier) to increase the surface area . Nematode inoculum size is an important factor. For Heterorhabditids optimum inoculum sizeis 107 IJs per flask and for steinernematids is 106 IJs per flask . The relationship between inoculum size, population development and final IJs population helps in improving the efficiency of commercial nematode production. Advantage is that investment is less; risk of process failure is partitioned over small production units. But it is labour intensive, vulnerable to contamination and uneven distribution of nematodes in medium prevents systematic sampling and thus improvement of the technique. Liquid culture: Stoll used a liquid medium containing raw liver extract and incubated the cultures on a shaker in dark. The nematodes developed and produced offspring. Buecher & Hansen

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improved upon this method by simply bubbling sterile air through liquid media in bottles which led to increase in scale-up production volume. At present, S. carpocapsae, S. glaseri and S. riobrave can be consistently and efficiently produced in 7500-80,000 litre fermenters with a yield capcity upto 1,50,000 IJs per ml. Medium composition, oxygen supply, temperature, quality of symbiotic bacteria, recovery and inoculums size are some of the factors influencing yield. Disadvantages are high cost of labour, high cost of equipments, high chances of contamination and loss of quality in some cases. Formulations: Formulated products are prepared to enhance : storage, transportation, ease of use, activity of the organism, activity of pesticides and maintaining quality. In Inert Carrier; Nematodes are placed in inert carriers viz., sponge or vermiculite. This allows free gaseous exchange and movement of nematodes. It is a convenient means to transport small quantities of nematodes. The disadvantage is- since nematodes are active, stored energy reserves are depleted. Nematodes tend to come out of the inert material. These die due to want of moisture. In functional ingredients: absorbants , adjuvants , antibiotics , antidesiccants and UV protectants etc. are added to reduce nematode activity and metabolism. Some Formulations are: Alginate Gels, Flowable Gels , Attapulgite Clay Chips, Water dispersible granules, Cadaver based formulations. Application Technology: Common nozzle type sprayers with openings larger than 50µm and operating pressure< 2000K Pa are used. Spray equipments used are: tractor drawn sprayers, backpack sprayers, hand injecting guns etc., sprinkler or Drip irrigation systems. Ways of Application : Soil Application, foliar application, application to trap crops, application to plant propagation material, sound traps, use of nematodes in insect bait traps .It all depends on the type of pest to be controlled and the environment in which EPNs are to be used. Undisturbed ecosystems or closed environments such as mushroom cultivation beds are ideal environments for EPNs to reproduce and persist. EPNs (S. feltiae) have been successfully used against sciarid and phorid flies in glasshouse crops and mushroom houses, against root weevils in citrus. Mole crickets in turf grass have also been efficiently controlled by S. scapterisci. SELECTED READINGS Gaugler R & Kaya HK. 1990. Entomopathogenic Nematodes in Biological Control. CRC Press. Gaugler R. 2002. Entomopathogenic Nematology. CABI. Grewal PS, Ehlars RU & Shapiro DI. 2005. Nematodes as Biocontrol Agents. CABI. Nguyen, K. B. & Hunt, D. J. 2007. Entomopathogenic Nematodes: Systematics, Phylogeny and Bacterial Symbionts. Nematology Monographs and Prespectives. Vol. V. Brill Leiden. Walia, R. K. & Bajaj, H. K. 2014. A Text Book on Introductory Nematology 2nd edition. ICAR, N. Delhi. Multiple choice questions 1. Red colour in insect cadavers is due to infection of a). Steinernema b).Heterorhabditis

c). Xenorhabdus d). Photorhabdus 2. EPNs are found only in

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a). Tropical areas b). Sub tropical areas c). Temperate areas c). All of the above 3. Steinernema kushidai can be cultured easily on a). Galleria larvae b). Corcyra larvae c). Helicoverpa sp. d).Scarabaeid beetles 4. Steinernema sp. used successfully for control of mole crickets is a). S. feitae b). S.carpcapsae c). S. scapterisci d). S. glaseri 5. Which of the following is not a formulation of EPNs a). Water dispersible granules b). Sodium alginate beads c).Host cadavers d). Charcoal powder 6. Hermaphroditic females are found in a). Steinernema only b).Heterorhabditis only c). Neither d). Both

7. Bursaphelenchus and Rhadinaphelenchus in insects are a). External parasites b). Internal parasites c). Symbiotic association c). Phoretic association 8. In Hetrorhabditis bacterium is located in IJs a). Oral cavity b). Oesophagus c). Intestine d). Rectum 9. Association between EPNs and bacteria is: a) antagonistic b). neutral c).phoretic d). Mutualistic 10. EPNs can be applied with sprayers with Nozzle size: a). >50µ b).< 50µ c). =50µ d). > 100 µ 11. DD 136 is the name given to: a). A fungus b). A protozoan c). An EPN d). A bacterium

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