Eggplant Borer: Biology, Current Farm Practices and ...

Eggplant Borer: Biology, Current Farm Practices and their Implications in Insecticide Resistance Management

Eggplant Prod’n in the Philippines Eggplant is a very important vegetable crop in the Philippines

  

#1 in area of production among top vegetables #1 in volume of production among top vegetables Contributes Php 2.5 Billion annually to agriculture

Source: BAS CropStat, 2010

Top 10 eggplant producing provinces in the Philippines (in metric tons, BAS CropStat, 2010) 9. Ilocos Norte – 5,434.12 1. Pangasinan – 62,842.08 8. Tarlac – 5,997.61 6. Batangas – 6,751.00

7. Cagayan – 6,400.06 4. Isabela – 9,209.99 5. Nueva Ecija – 6,960.25 2. Quezon – 28,017.85

3. Iloilo – 10,090.48

10. N. Cotabato – 5,275.87

Profitability of Eggplant Production (per farm) PROVINCE Pangasinan

Batangas

Quezon

ACROSS PROVINCES

244,181

39,324

177,034

165,060

Labor

5,827

20,456

48,670

21,960

Seeds

1,229

1,072

2,273

1,470

Fertilizer

8,237

1,471

2,542

4,666

Pesticides

13,349

1,624

10,858

9,193

Herbicides

373

19

29,016

24,642

64,344

37,455

215,165

14,682

112,690

127,606

ITEM

Return Expenses

Total

Net Cash Income

-

166

Source: Quicoy, 2010

Major problem in eggplant production Arthropods considered by farmers as major pests problem in eggplant production in five major growing areas of Luzon (Navasero et al. 2007)

Eggplant Borer (EB)

Photo courtesy of Rao, 2010

Pest

% of Farmers 100.00

Leafhopper

59.38

Whitefly

34.38

Thrips

21.88

Mites

18.74

Cutworm

18.74

Leaf miner

9.38

Flea beetles

6.25

Aphids

3.13

Lady beetles

3.13 Eggplant Borer (EB)

Major problem in eggplant production EB attacks the fruits, flowers and flower buds, shoots, petioles and midribs resulting in:  

Up to 70% yield loss Lower average yield compared to other Asian countries

Nature of damage of EB… On Leaves - Wilting of whole or portion of leaf resulting from the boring of early instar larvae into petiole and major leaf veins. On Flowers - Direct feeding may result in partially damaged stamen and corolla (1) and partially or totally eaten up pistil (2). May result in flower fall and misshapen fruits (3). 1

2

3

Nature of damage of EB… On Shoot - Feeding by early instars larvae into the xylem layer result in wilting (1) and feeding by later instars into the tender stem result to further wilting (2) and eventually to breaking and dryingup (3).

3

2

1

Nature of damage of EB On fruit- Circular holes, varies with the size of the larva at time of entry

1 2

a

b

Entry holes made by early instars are discernable only as small dot markings surrounded by slight depression (1) compared to entry holes of later instars (2). Exit holes are bigger and without excreta (a) Entry holes are usually covered with frass (b)

MANAGEMENT PROGRAM FOR EFSB

Srinivasan R. 2008. Integrated pest management for eggplant fruit and shoot borer (Leucinodes orbonalis) in South and Southeast Asia: past, present and future. Journal of Biopesticides 1(2): 105–112.

Current Farm Practices… Farmers usually plant long and purple varieties that are mostly hybrid and susceptible to EFSB Open pollinated and moderately resistant varieties are not preferred

Some local eggplant varieties with known level of resistance to EFSB

Natural enemies of EB A B

C

Ichneumonid and braconid parasitoids of FSB: A) Apanteles sp. (left – cocoon, right – adult), B) Chelonus sp. and C) Xanthopimpla puctata

Natural enemies of EB A

B

C

A) Trathala flavoorbitalis (inset – preserved specimen), B) Brachymeria obscurata, C) Brachymeria sp.

Natural enemies of EB Natural Enemy

Reference(s)

Apanteles sp.

Navasero, 1983; Baltazar, 1991

Brachymeria obscurata

Navasero, 1983

Brachymeria sp.


Cardiochelis sp.

Baltazar, 1991

Chelonus sp.


Trathala flavoorbitalis*

Alpuerto, 1994

Trichogramma spp.

Alpuerto, 1994

Xanthopimpla puctata

Navasero, 1983

Undetermined dermapteran

Navasero, 1983

*Considered the most promising but data on parasitization both in the laboratory and in the field (Alpuerto, 1994; Solleza and Javier, 2009) ranges only from 4-25%, too low to be considered truly promising.

Bio-control agents tested against EB

Trichogramma

Common earwig, Euborella annulipes

No conclusive data have been generated showing the effectiveness of these biological control agents

Bio-control agents tested against EB

Use of Orius, Trichogramma and Euborella

Alternate hosts of EB List of alternate hosts Foreign records Major hosts: Solanum tuberosum (potato) Minor hosts: Ipomoea batatas (sweet potato) Lycopersicon esculentum (tomato) Pisum sativum var. arvense (Austrian winter pea) Solanum indicum Solanum myriacanthum Solanum torvum (turkey berry) Wild hosts: Solanum gilo (gilo) Solanum nigrum (black nightshade) Physalis peruviana Physalis minima Local records Minor hosts: Solanum tuberosum Lycopersicon esculentum Wild hosts: Solanum nigrum

Given the narrow host range, use of alternate hosts as refuge for susceptible EB appears to be of limited application

Alternate hosts of EB

SOLANUM NIGRUM

Alternate hosts of EB

PHYSALIS ANGULATA (to be evaluated)

Eggplant as refuge: enhancing ovipositional preference of EB?

Plot IA and IIB were sprayed with a selective insecticide for sucking insects and with known phytotonic effect

Eggplant as refuge: enhancing ovipositional preference of EB? Plot I

Leafhopper and borer: Increase in population of hopper result in lower population of EB.

Population density

500 400 300

hopper A

200

hopper B

100

borer A

0

borer B

-100

Plot II 500

Population Density

Conversely, decrease in the population of leafhopper result in higher population of EB

400 300

hopper A

200

hopper B

100

borer A

0

borer B

-100

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Weeks After Transplanting

IPM: Other methods of control Physical control. The use of barrier structures like net installed around the field was effective in preventing infestation (Arida et. al, 2004).

Habitat manipulation. Use of vegetables and other plants as intercrop acting either as refuge or attractant for natural enemies, and as repellent to the pest (Gonzales,et al, 2004, Calumpang et al. 2005) had been studied. However, the level of control through these methods had not been established in on-farm trials. Cultural control. These include sanitation specifically removal and destruction of damaged plant parts. Collected damage fruits and shoots should be burned or buried. Use of sex phermone. Use of synthetic sex pheromone showed that an increase in number of male caught correspond to a decrease in number of shoot and fruit damaged by the eggplant borer (Arida, 2004). Roxas et al (2006) reported an average of only 15% fruit damaged in fields where the pheromone was used compared to 30% in fields regularly sprayed with insecticides and 70% in untreated fields.

The use of virgin females as alternative to phermone. In a trapping experiment done in Pangasinan using a single virgin female, 970 males were baited in one night alone (Gonzales,et al, 2004).

IPM: Other methods of control

Deleafing

Kadios as wind break

Removal of damaged plant parts

Dense planting 1m x 0.4m

IPM: Other methods of control Summary of impacts of CIP-related technologies: 12 case studies Varieties East Africa: Potato China: Potato Peru: Potato

IPM

Tunisia: Potato Dom. Republic: Sweetpotato Peru: Potato Cuba: Sweet potato

Seed

Tunisia: Potato Vietnam: Potato (Rapid multipl’n) India: Potato China: Sweet potato Vietnam: Potato (TPS)

10.92 14.73 2.2

2.15 0.36 0.67 6.3 1.99 0.510 1.911 132.812 0.8

Values are ratio of cost of return (calculated benefits) over the cost of research fund.

IPM researches had lower cost-benefit ratio indicating low adaption compared with researches involving introduction of new varieties/seeds.

Source: Fuglie, K. 2005. Assessing impact: Field Tested Methods and Tools. CIP- UPWARD Meeting on Participation and Change: Enhancing Research for Impact. Hanoi, Vietnam January 2005.

Current Farm Practices… Farm Practice

Province Pangasinan

Batangas

Quezon

Yes

No

Yes

No

Yes

No

IPM

6.48

93.6

0.0

100.0

0.0

100.0

Crop rotation

57.4

42.6

50.0

50.0

7.4

92.6

Cover cropping

46.81

53.19

0.0

100.0

3.7

96.3

Chemical pest control

95.7

4.3

96.7

3.3

100.0

0.0

Mulching

4.5

98.3

3.3

96.7

0.0

100.0

Biological pest control

8.5

91.5

43.3

56.7

0.0

100.0

 

Up to 80x pesticide sprays per season = every other day cocktail of insecticide application 25% higher cost of production due to chemical sprays Source: Quicoy, 2010

Current Farm Practices… Insecticide spray interval practiced by farmers in major eggplant growing areas of Luzon.

Spray interval (in days)

% of Farmers

Number of brands of insecticides used by farmers in major eggplant growing areas of Luzon.

No. of brands

% of Farmers

No spraying

9.38

0

9.38

1

9.38

1

6.25

2

25.00

2

9.38

3

6.25

3

15.63

4

21.88

4

25.00

5

3.13

5

12.50

7

12.50

6

9.38

Occasional

12.50

7

3.13

8

6.25

9

3.13

Source: Navasero et al. 2007

Current Farm Practices… Usage of insecticides (by active ingredient) on eggplant in major growing areas of Luzon.

Active Ingredients

% of Farmers

Cartap hydrochloride

57.36

Triazophos

31.26

Methomyl

28.13

Carbaryl

25.01

Thiametoxam

21.88

Chlorpyrifos (+ BPMC)

21.88

Fipronil

15.63

Imidacloprid

15.63

Flubendiamide

12.50

Lambdacyhalothrin

12.50

Profenopos

12.50

Methamidophos

12.50

Cypermethrin

12.50

 Mostly broad spectrum  Representing different chemical groups  Different mode of actions  Mostly contact or with limited translaminar movement  Concealed larvae are less likely to get in contact with the applied pesticide  Many individuals including susceptible ones escape unharmed

 No confirmed full-brown resistance (Source: Navasero et al. 2007)

Current Farm Practices… Source: Lu, 2010

Survey limited to Sta Maria, Pangasinan with 100% of farmers using the diamide product. May also be true in other places.

Selection pressure for resistance is dramatically increased.

RESISTANCE may developed within 2-3 yrs of commercial availability Cheng et al. (1990) for IGR Zhao et al. (2002) for spinosad Kao and Cheng for fipronil - This might be the case of DIAMIDE on FSB

Multiple Resistance in DBM*

COMPOUNDS

RESISTANCE RATIO (DBM)

BTL Sus. strain 1.0

Atok 33.1

Calamba 37.6

Majayjay 19.5

Fipronil

1.0

150.7

102.1

21.3

Cypermethrin

1.0

358.0

390.2

298.3

Cartap

1.0

15.8

7.7

4.4

Spinosad

1.0

8.8

9.5

16.7

Indoxacard

1.0

3.7

2.4

0.6

Flubendiamide

1.0

0.8

0.9

0.2

Chlorantraniliprole

1.0

0.5

1.0

0.7

Methamidophos

*Sarmiento and Ocampo. 2010. Variability in response to insecticides of field populations of diamondback moth, Plutella xylostella (Linnaeus), in the Philippines. Philippine Entomologist 24(1): 39-76.

Multiple resistance in FSB is also possible

Life Cycle of EB Total life cycle: 22-31 days Egg

 Should not exposed to insecticides with same mode of action (MoA) for more than 4 weeks during the early stage of cropping period.

(3-4 days)

Adult Female (4-6 days)

Larva (9-14 days)

Adult Male (2-4 days)

Pupa (8-9 days)

 Exposure should be 3 weeks or shorter during the latter stage of cropping period when overlapping generation of the pest already exist.

Biology: Life Cycle of EFSB Implications to IRM

1st spray period

1st spray period

2ND t spray period

MOA 1

MOA 2

MOA 1

Overlapping generations from successive emigrating populations

SEEDBED

VEGETATIVE STAGE

FLOWERING/FRUITING STAGE

WEEKS AFTER TR ANSPLANTING 4

3

2

1

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

Based on IRAC window (1 generation) recommendation. However, because of overlapping generation portion of the population may be exposed for two generation.

Biology: Life Cycle of EFSB Implications to IRM MOA 1

MOA 2

MOA 3

MOA 1

MOA 2

Overlapping generations

SEEDBED

VEGETATIVE STAGE



3

2

1

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

Modification to minimize/prevent exposure of more that 1 generation to the same MOA

16

Insecticide management under multipest situations

SEEDBED

VEGETATIVE STAGE



3

2

1

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

EFSB Cutworm, Leafhopper, Whitefly, Aphids, Thrips, Mites

Leafhopper, Whiteflies Thrips, 12 or 28-Spotted lady beetles, Flea beetles, Red spider mites, Broad mites Aphids Cutworm

16

Insecticide management under multipest situations Occurrence of pests and chemical spraying in an actual eggplant production (Nov. 2006 - Feb. 2007, Calamba City) Pests

Weeks after transplanting 1

Leafhopper

2

3

4

5

6

7

8

9

10

11

12

13

14

15

X

Whitefly Thrips Mites

X

Eggplant borer Cutworm

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

3

4

5

6

7

8

9

10

11

12

X 1

2

1 – product specific for sucking insect;

2 – product with efficacy to mites and cutworm

3, 5, 6, 8, 10, 11 – products for borer;

4, 7 – product with efficacy to borer, mites and thrips (same product with 2)

9, 12 – 2 products, one for borer and one for thrips and whitefly