Screening for drought tolerance in mungbean

Legume Research, 40 (3) 2017 : 423-428

AGRICULTURAL RESEARCH COMMUNICATION CENTRE

Print ISSN:0250-5371 / Online ISSN:0976-0571

www.arccjournals.com/www.legumeresearch.in

Screening for drought tolerance in mungbean M. Prakash*, B. Sunilkumar, G . Sathiyanarayanan and J. Gokulakrishnan Department of Genetics and Plant Breeding, Faculty of Agriculture, Annamalai University, Annamalai Nagar-608 002, India. Received: 05-09-2015 Accepted: 13-02-2016

DOI:10.18805/lr.v0iOF.11045

ABSTRACT Field experiments were conducted to screen the mungbean genotypes based on root characters and root penetration ability. Observations on root and shoot characters viz., root length, shoot length, number of roots, root diameter, fresh weight of root, fresh weight of shoot, dry weight of root, dry weight of shoot, root volume, growth and yield parameters viz., plant height, number of branches, number of pods per plant, number of seeds per pod, 100 seed weight, seed yield per plant were recorded. Based on the root characters, the genotypes HUM 1, VMGG 67, VMGG 82, VMGG 83 and VMGG 90 were found to be promising. They also performed well in the field experiments. These genotypes were crossed with high yielding varieties like VBN 1, VBN 2, VBN 3 and KM 2 to get F1.Among the 20 crosses obtained, three crosses VMGG-83/VBN 2, VMGG-90/VBN 3 and VMGG-83/VBN 1 were found to perform well in F2 and they will be forwarded to next generation. Key words: Drought, Growth, Mungbean, Photosynthesis, Root study, Yield. INTRODUCTION Moisture stress is a major constraint to crop production worldwide. In developing countries, large arable land experiences moisture stress. Moisture stress is a major constraint in the production and yield stability of mungbean. For developing high yielding varieties under moisture stress conditions, the common methods employed are direct selection and heterosis breeding. However, this approach is time consuming and labor intensive, because yield is a highly quantitative trait. The alternative strategy that has succeeded in a few crops is using secondary traits like rootrelated traits. Pulses play a vital role in providing a balanced protein component in the diet of the people and also play a major role in crop rotation, diversification and productivity by enriching the soil fertility. They also play an important role in Indian agriculture constituting the major source of essential amino acids for predominantly vegetarian population of India (Arumugam et al., 2010). In the global scenario, India is the largest producer of pulses in the world with 25% share in global production. The area under pulses crops in India during 2011-12 was around 23.63 million ha with production of 14.76 million tonnes and productivity of about 625 Kg.ha-1 (Anonymous, 2011). These are grown mostly in marginal and rainfed areas and the major constraint for higher productivity is inadequacy of moisture. Hence, developing a moisture stress tolerant mungbean is necessary for cultivation in these areas. Even though it thrives moderately under drought prone condition, greater variability exists for yield performance *Corresponding author’s e-mail: [email protected]

of different genotypes. Eventhough different workers used different methods to evaluate genetic differences in drought tolerance (Bidinger et al., 1982), the present investigation has been planned to find out the simple technique using root parameters to identify the genotypes tolerant to drought. Roots play an important role in water stress tolerance by reduction in leaf expansion and promotion of root growth. Root length at seedling stage provides a fair estimate about the root growth in field (Ali et al., 2011; Rajendran et al., 2011). Vincent (2014) also proposed roots as a major avenue of research to improve crop adaptation under water stress conditions. In general, deeper and more profuse root systems could be able to tap extra water from the soil profile and alleviate drought effects. Root traits like root length, number and root depth, have long been seen as important traits to improve crop adaptation to water stress. With this background, studies were undertaken to screen the mungbean genotypes based on root characters and root penetration ability in a specialized structure. The genotypes best performed were crossed with high yielding varieties to get crosses which are moisture stress tolerant and high yielding. MATERIALS AND METHODS Eighty nine genotypes of mungbean obtained from various sources were evaluated for root characters and sowing was taken up in a specialized structure (with sand and bricks) meant to study root characters. The experiments were conducted at the Department of Genetics and Plant Breeding, Faculty of Agriculture, Annamalai University, Annamalai Nagar (11°24’N latitude and 79°44’E longitude

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with an altitude of +5.79 mts above mean sea level) from 2012-2014. Root Study : Seeds of eighty nine genotypes were sown in line to sand medium made specially to study root characters. At peak vegetative stage, the seedlings were pulled out from the structure by washing the roots with water. Root and shoot characters viz., root length, shoot length, number of roots, root diameter, fresh weight of root, fresh weight of shoot, dry weight of root, dry weight of shoot, and root volume were recorded (Table 1). Ten normal seedlings were taken at random and the length between collar region to tip of the primary root were measured and the mean value was recorded as root length in centimeter. The same seedlings taken for measuring root length were used for shoot length measurement. The length between the collar region to tip of the primary shoot was measured in centimeter and the mean value was recorded as shoot length in centimeter. Number of roots per plant was counted and expressed as number per plant. Root diameter was measured using a vernier caliper and expressed in cm. Fresh weight of shoot and root were

also measured and expressed in g plant -1. Ten normal seedlings used for growth measurements were placed in a paper cover and dried under shade for 24h and then kept in hot air oven at 100oC for 24h. The dried seedlings were cooled in a desiccator for 30 minutes and the dry weight of root and shoot were recorded and was expressed in mg. Root penetration study: Root penetration study was conducted to screen drought tolerant and susceptible genotypes. In this study, a controlled environment was created by using a thin layer of paraffin wax and white petroleum ether in 2:1 ratio to simulate a hard pan. A thermo cool was made with holes and its bottom was covered with wire mesh. Then the wire mesh was wrapped with aluminium foil to prevent leakage of paraffin wax solution. The 2:1 mixture of paraffin wax and white petroleum ether was poured into the holes of thermo cool to form 2-3 mm thin layer and the entire set up was kept in room temperature for 20-30 minutes to allow it to cool. Then the aluminium foil was removed. Two-third of the holes in thermo cool were filled with sand and sowing was taken up. The entire set up

Table 1: Mean value of root characters in mungbean. Genotypes

Root length (cm)

CGG-09-03 CGG-09-07 CGG-09-14 CGG-09-15 CGG-09-17 CGG-09-18 CGG-09-23 CGG-09-24 RM8-653 RM8-659 RM8-661 RM8-662 RM8-664 RM8-665 RM8-667 RM8-668 CO-6 CO-7 AU-CULTURE-1 HUM 1 CGG-09-04 CGG-09-05 CGG-09-06 CGG-09-08 CGG-09-09 CGG-09-10 CGG-09-12 CGG-09-13 CGG-09-16 CGG-09-19 CGG-09-20

33.61 26.22 51.87 52.66 42.47 41.41 35.53 53.48 44.35 50.15 44.25 38.25 51.42 48.52 48.25 42.41 45.19 47.77 48.56 55.21 48.27 42.43 47.18 39.86 38.52 44.17 53.70 54.11 51.21 44.75 41.43

Shoot length Number of (cm) roots 21.70 17.55 19.82 32.28 24.73 28.40 24.61 28.51 24.48 26.48 34.45 24.42 25.24 34.54 17.86 19.84 22.41 22.42 27.15 32.14 29.87 24.22 28.52 25.23 34.13 24.23 24.26 25.77 32.71 14.97 22.78

4.41 3.71 5.72 5.21 3.64 4.60 4.35 5.72 5.14 5.14 4.41 3.14 3.45 5.12 3.42 4.36 4.74 4.11 3.74 6.84 4.56 3.46 4.23 4.74 4.16 4.42 5.43 5.51 5.34 2.41 3.14

Root diameter Root fresh Shoot fresh Root dry Shoot dry Root (cm) weight (g) weight (g) weight (g) weight (g) volume 0.31 0.22 0.37 0.35 0.33 0.38 0.34 0.31 0.31 0.41 0.38 0.34 0.44 0.41 0.32 0.34 0.34 0.34 0.54 0.55 0.53 0.34 0.41 0.34 0.34 0.34 0.31 0.30 0.31 0.27 0.29

2.11 1.32 4.12 5.25 2.11 2.14 2.14 5.12 2.52 3.41 3.15 3.42 3.41 3.36 2.74 2.51 3.41 2.89 3.45 4.86 3.15 2.52 3.41 2.54 3.41 1.16 2.37 1.65 3.28 1.71 2.64

8.18 3.31 11.52 11.74 6.93 9.16 6.21 5.15 6.12 11.23 12.15 10.56 11.87 10.66 8.56 8.51 15.80 7.62 11.50 11.21 12.65 6.82 11.28 6.51 10.40 4.91 7.15 4.32 11.25 3.45 6.47

0.225 0.213 0.618 0.587 0.419 0.385 0.349 0.576 0.426 0.428 0.448 0.344 0.472 0.445 0.445 0.513 0.519 0.416 0.455 0.778 0.449 0.519 0.519 0.525 0.422 0.416 0.659 0.628 0.642 0.356 0.399

0.91 0.51 1.35 1.71 0.58 1.41 0.38 0.71 0.85 1.82 2.35 1.41 1.52 1.51 0.74 1.41 1.58 1.04 1.25 2.14 2.64 1.25 2.24 1.02 1.41 1.42 1.25 1.45 1.82 0.65 0.49

1.1 0.54 3.51 5.25 1.45 3.54 1.41 1.74 2.65 4.41 5.26 5.26 4.71 6.48 3.51 2.79 5.28 3.25 5.74 5.12 9.52 2.64 3.43 2.51 5.74 3.23 3.49 3.25 3.49 1.58 2.51 contd.......

Volume 40 Issue 3 (June 2017) CGG-09-21 44.28 CGG-09-22 35.85 RM8-651 38.55 RM8-652 38.75 RM8-654 34.25 RM8-655 42.15 RM8-656 47.21 RM8-657 39.14 RM8-658 38.46 RM8-660 39.41 PUSA 9972 41.21 IPM 02-3 (BLACK)26.90 ML 5 34.26 VMGG 67 58.82 IPM 02-14 40.24 CO GG 912 39.26 PUSA 9072 41.31 PDM 178 41.39 IPM 02-03 (RED) 42.87 IPM 02-10 44.56 IPM 02-17 45.40 PDM 54 51.25 PDM 288 42.50 ML 512 42.71 PANT MUNG 5 45.68 IPM 05-3-22 41.60 PDM 262 38.12 IPM 05-2-8 39.8 IPM 02-16 42.17 ML 1257 42.26 IPM 02-1 41.57 IPM 306-1 43.88 SML 48 43.58 IPM 3-2 40.61 SML 191 42.66 UPM 98-1 43.27 PUSA BOLD 2 41.41 PDM 5 41.71 B-9 40.01 ML 682 40.85 PDM 11 42.50 VMGG 90 58.64 IPM 306-6 42.90 IPM 9901-03 39.25 IPM 9901-125 34.35 IPM 02-19 48.25 IPM 02-23 37.92 V 3518 37.44 AMULYA 41.93 HUM 12 51.22 SML 47 50.95 IPM 9901-10 52.10 IPM 2K14-9 50.42 PDM 87 54.58 PDM 139 52.50 LGG 410 53.00 VMGG 82 53.69 VMGG 83 57.46 CD(p=0.5) 3.6

21.27 24.55 21.56 17.62 21.54 19.41 21.45 19.58 20.41 20.21 25.04 17.87 26.82 35.45 33.22 25.30 32.26 21.36 24.26 23.27 27.83 33.25 23.10 26.48 24.16 22.15 26.74 30.15 23.42 30.15 32.17 23.46 31.28 24.33 31.32 25.33 27.41 26.37 35.81 18.87 25.08 34.65 19.17 25.75 16.96 18.42 25.23 25.30 28.82 27.49 26.59 24.16 23.23 24.72 25.48 25.15 33.56 33.85 2.8

4.14 3.24 2.21 2.41 2.74 4.41 5.12 3.74 4.52 4.42 4.49 2.26 4.84 8.26 2.78 3.88 3.34 3.56 4.28 4.30 3.66 4.78 3.50 4.40 4.76 4.18 3.94 4.46 3.99 3.98 4.17 4.78 4.19 3.30 3.98 4.54 3.89 4.26 1.17 3.11 4.84 8.12 4.15 3.75 4.83 4.29 3.52 3.37 3.64 5.81 8.99 5.70 5.61 6.07 5.72 5.35 7.65 7.22 1.4

0.28 0.30 0.24 0.21 0.23 0.27 0.34 0.31 0.30 0.35 0.34 0.45 0.32 0.62 0.27 0.39 0.58 0.33 0.23 0.29 0.42 0.62 0.32 0.39 0.47 0.36 0.37 0.43 0.42 0.56 0.54 0.28 0.34 0.28 0.47 0.28 0.42 0.37 0.38 0.25 0.31 0.62 0.26 0.41 0.24 0.23 0.34 0.35 0.38 0.38 0.32 0.30 0.32 0.33 0.35 0.37 0.58 0.68 0.6

1.42 2.85 1.27 0.74 1.54 2.10 1.58 1.45 2.65 1.99 2.24 1.65 3.47 5.13 4.99 2.17 2.90 1.92 2.18 2.28 4.50 5.99 5.08 4.38 4.71 3.99 3.41 4.71 3.82 3.71 3.90 3.11 2.82 3.19 4.82 2.28 2.46 2.37 4.22 1.70 2.26 5.25 1.73 1.36 1.53 1.66 3.03 3.01 3.32 2.94 4.92 4.94 4.28 4.13 5.73 4.38 5.13 5.34 0.7

425 3.41 5.45 3.54 2.22 4.25 6.13 3.12 6.98 5.42 6.74 5.68 3.20 9.50 12.54 10.62 5.91 10.39 5.49 7.62 8.50 10.63 10.93 9.51 10.12 11.58 7.60 11.94 10.23 9.35 11.15 11.54 7.96 7.96 8.78 8.24 7.89 6.33 7.62 8.09 4.76 5.07 12.88 3.58 3.83 4.10 2.63 7.84 7.90 8.40 9.41 6.78 7.32 7.16 9.14 9.53 8.29 12.68 13.47 1.6

0.325 0.245 0.271 0.324 0.326 0.453 0.236 0.272 0.423 0.554 0.268 0.308 0.466 0.845 0.753 0.313 0.463 0.184 0.285 0.353 0.441 0.450 0.511 0.515 0.432 0.430 0.461 0.525 0.441 0.527 0.551 0.466 0.422 0.416 0.537 0.322 0.538 0.297 0.543 0.184 0.394 0.866 0.229 0.330 0.169 0.207 0.441 0.452 0.497 0.624 0.565 0.771 0.637 0.672 0.768 0.591 0.888 0.812 0.3

0.52 0.64 0.27 0.44 0.58 0.65 0.45 0.85 0.67 0.44 0.94 0.89 0.98 1.85 1.43 0.69 1.81 0.45 0.54 0.83 1.40 2.25 1.38 1.34 1.23 0.52 1.41 1.26 0.96 1.57 2.57 1.06 1.77 1.34 1.78 0.96 0.95 1.16 1.84 0.35 0.81 2.25 0.38 0.43 0.37 0.45 1.04 0.98 1.20 1.07 0.73 0.76 0.67 1.05 1.23 1.33 2.34 1.88 0.7

2.14 1.68 0.48 2.14 1.58 1.67 2.11 2.56 2.47 2.29 1.15 0.89 2.38 4.68 3.85 0.58 2.68 0.96 0.98 2.56 3.87 4.40 3.81 3.48 5.38 3.36 2.66 4.66 3.46 4.71 4.11 2.75 2.58 2.76 5.88 3.17 3.63 4.30 4.69 1.54 2.83 5.26 3.35 2.58 0.79 2.12 2.03 1.89 2.33 1.98 1.09 1.50 1.75 2.47 3.06 3.26 5.45 5.23 1.1

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was kept in coarse sand bed for allowing root development. After 18 days, thermo cool set up was removed and root penetration, root growth were observed. The roots of the genotypes which have penetrated 2:1 mixture of paraffin wax and white petroleum ether, and which have long and more number of roots were identified as drought tolerant. Based on the root characters studied and root penetration ability. the genotypes HUM 1, VMGG 67, VMGG 82, VMGG 83 and VMGG 90 were found to be promising. The above genotypes also performed well in the field experiments. These genotypes were crossed with high yielding varieties like VBN 1, VBN 2, VBN 3 and KM 2 to get F1. Among the crosses, VMGG-83/VBN 2, VMGG-90/ VBN 3 and VMGG-83/VBN 1were found to perform well in F2 (Tables 2 and 3).

was recorded from ten seedlings selected at random which were uprooted with the intact root system and were washed to remove the soil particles, dried under shade for 24h and then in the hot air oven maintained at 100oC for 24h. The dried plants were cooled in a desiccator for 30 minutes and the mean weight was recorded in grams. Number of days taken from sowing to 50 per cent flowering was recorded and the mean value is expressed as days to 50% flowering in whole number.

Field Study Growth parameters : Field experiment was conducted during early summer by adopting randomized block design with three replications. The crop was raised with the spacing of 30 × 10 cm and recommended package of practices for mungbean were followed. The experiment was carried out under natural conditions and there was no rainfall during the experimental period. The moisture stress was induced by withholding irrigation at 25 DAS. All the growth and yield parameters were recorded.

Yield parameters: Numbers of days taken from sowing to 50 per cent flowering in each genotype was recorded and the mean value was expressed as days to 50% flowering in whole number. Total number of pods in marked ten plants in each genotype was counted and mean number per plant was recorded replication wise and the mean was expressed in whole number. The pods from ten randomly selected plants earlier tagged were separately harvested and the seeds from each pod were separated, counted and averaged out to get number of seeds per pod. Hundred seeds collected from the matured pods were weighed and expressed in grams. Seeds from the five marked plants were collected manually, cleaned, dried to constant moisture content and weighed. The mean seed yield was recorded and expressed as g plant-1. All the data were analysed statistically with appropriate tools and expressed as mean values.

The height of the plant was measured from the ground level to the tip of the plant and expressed in cm plant-1. Total number of branches in each plant was recorded and expressed as number of branches. The biomass production

RESULTS AND DISCUSSION The results obtained for the nine root and shoot characters viz., root length, shoot length, number of roots, root diameter, fresh weight of root, fresh weight of shoot,

Table 2. Performance of F1 generation of mungbean genotypes. Hybrids

HUM 1/VBN 1 HUM 1/VBN 2 HUM 1/VBN 3 HUM 1/KM 2 VMGG-67/VBN 1 VMGG-67/VBN 2 VMGG-67/VBN 3 VMGG-67/KM 2 VMGG-82/VBN 1 VMGG-82/VBN 2 VMGG-82/VBN 3 VMGG-82/KM 2 VMGG-83/VBN 1 VMGG-83/VBN 2 VMGG-83/VBN 3 VMGG-83/KM 2 VMGG-90/VBN 1 VMGG-90/VBN 2 VMGG-90/VBN 3 VMGG-90/KM 2 CD(p=0.5)

Days to 50 percent flowering 29.67 28.14 29.12 31.33 34.46 31.14 29.54 28.63 31.13 29.67 29.47 28.89 29.33 31.55 30.77 29.55 29.66 30.66 28.89 29.33 3.14

Plant height (cm) 56.67 61.70 54.13 60.22 51.11 54.81 36.77 60.91 45.77 36.11 4366 36.00 43.96 40.66 47.13 53.61 53.30 54.46 54.91 43.11 5.22

Number of branches per plant 2.00 1.63 1.67 2.67 2.00 3.00 3.67 3.33 2.67 3.33 2.66 2.22 2.33 2.44 2.22 3.22 2.55 2.88 1.88 1.33 0.02

Number of pods per plant

Number of seeds per pod

100 Seed weight (g)

16.22 17.88 16.44 18.22 18.12 18.77 20.42 19.88 19.66 18.11 19.55 14.44 16.66 16.88 14.77 14.55 14.88 13.22 14.66 12.66 1.57

9.26 9.45 9.88 10.75 10.74 9.32 11.66 11.41 10.59 9.34 10.35 9.91 9.32 10.75 10.55 10.67 10.36 10.18 10.72 8.77 2.24

3.40 3.07 3.04 3.20 3.40 3.31 3.14 3.20 3.27 3.33 3.16 3.10 3.10 3.42 2.98 2.97 3.28 3.10 3.26 2.94 1.15

Seed yield (g pl-1) 5.08 4.38 4.30 4.66 5.26 4.76 5.65 5.60 5.11 5.35 5.30 4.81 5.38 4.52 5.21 4.76 4.59 4.21 4.45 3.79 1.49

Volume 40 Issue 3 (June 2017) dry weight of root, dry weight of shoot, and root volume were recorded (Table 1), plant height, number of branches, number of pods plant-1, number of seeds pod-1, 100 seed weight and seed yield plant-1 (Tables 2 and 3) were presented in the following tables and discussed below. Root characters: Water stress affects almost each and every developmental stage of the plant. Root length is an important trait against drought stress in plant varieties and in general, varieties with longer root growth are supposed to have resistant ability for drought. Genotypes with faster elongation rates were also be more able to deplete soil water 120 cm below the surface. Under stress conditions, the number of lateral roots per unit of taproot length significantly increased, but no promotion of taproot length or diameter was observed. Significant reduction in seedling parameters may be attributed to their differential response in term of tolerance level to moisture stress. Similar observations were made by Bibi et al. (2010) and Ali et al.(2011). Considerable decrease in germination and fresh weight of seedlings of black gram (Vigna mungo L. Hepper) genotypes LBG20 and PU19 under stress was reported by Yadav et al. (2013). For shoot length, root length and number of roots, VMGG 67, VMGG90 and VMGG83 recorded first three places. In the case of root diameter, fresh weight of root and fresh weight of shootVMGG83, VMGG90 and VMGG67 performed well. Higher dry weight of root, dry weight of shoot and root volume were recorded in VMGG82 followed by VMGG90.HUM 1 performed well next to these genotypes for most of the root characters. Liu et al. (2005) reported significant correlations in soybean between drought resistance and various root traits such as dry weight, total length, and volume and number of lateral roots. Moisture stress suppressed shoot growth more than root growth and in certain cases root growth increased (Salih et al., 1999; 2000; Okçu et al., 2005; Bibi et al., 2010). Osmotic membrane stability of the leaf segment was found the most important trait, followed by root-to-shoot ratio and root length on the basis of their relationships with other traits for drought tolerance (Dhanda et al., 2004). Bibi et al. (2010) and Ali et al. (2011) also reported that significant reduction in seedling growth in terms of length, fresh and dry weight of shoot and root among the genotypes might be due to their differential response to moisture stress. These results are in

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consonance with the findings of the present study also. Sunilkumar et al. (2015) also studied influence of drought stress on root distribution in mungbean. Growth and yield parameters: HUM 1 X VBN 2 came to flowering earlier on 28.14 days followed by VMGG 67 X VBN 2 which took 28.63 days for 50 % flowering. Among the crosses, VMGG 83 X VBN 2 and HUM 1 X KM 2 took more number of days for 50 % flowering i.e., 31.55 and 31.33 days for 50 % flowering. In the case of plant height, HUM 1 X VBN 2 recorded higher plant height ( 61.70cm) followed by VMGG 67 X KM 2 which recorded 60.91 cm. Increase in biometric parameters may be traced to enhanced photosynthetic processes which might have been due to the inherent potential of the genotype. A similar report was made by Grade et al. (2014). For all the other growth and yield parameters except for 100 seed weight, i.e., number of branches, number of pods per plant, number of seeds per pod and seed yield, VMGG 67 X VBN 3 recorded higher values of 3.67, 20.42, 11.66, and 5.65 g pl-1 respectively which was followed by VMGG 67 X KM 2. In case of 100 seed weight, VMGG 67 X KM 2 recorded 3.20 g followed by VMGG 67 X VBN 3. Among the 20 F1 crosses, VMGG 90 X KM 2 recorded lowest values for all the growth and yield parameters. Higher yield recorded by VMGG 67 X VBN 3 could be due to increased yield attributing characters viz., number of pods per plant and number of seeds per pod. Based upon the yield performance in F1 generation, three crosses, VMGG 67 X VBN 3, VMGG 67 X KM 2 and VMGG 83 X VBN 1 were selected and forwarded to F2 generation. In F2 generation, VMGG 67 X VBN 3, recorded higher values for all the parameters i.e., number of branches, number of pods per plant, number of seeds per pod, 100 seed weight and seed yield, followed by VMGG 67 X KM 2.Increase in growth and yield parameters might have been contributed for enhanced yield in VMGG 67 X VBN 3 followed by VMGG 67 X KM 2 and VMGG 83 X VBN 1. Grade et al.(2014) also reported that increased yield could have been due to increased yield parameters like more number of branches, more number of pods per plant, seeds per pod and 100 seed weight. Reduction in biophysical charecters and seed yield in mungbean under moisture stress condition was also reported by Sunilkumar et al. (2015a).

Table 3: Performance of F2 generation of mungbean genotypes. Hybrids

VMGG67/VBN 3 VMGG 67/KM2 VMGG 83/VBN 1

Days to 50 percent flowering 28.16 28.19 29.48

Plant height (cm pl-1)

Number of branches per plant

54.27 52.91 59.76

2.64 2.48 2.34

Number of pods per plant 18.47 17.86 16.96

Number of seeds per pod 10.55 10.32 9.82

100 Seed weight (g)

Seed yield (g pl-1)

3.61 3.52 3.24

5.52 5.47 5.36

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