screening elite genotypes and ipm of defoliators in groundnut

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4. EXPERIMENTAL RESULTS The results of the present study on biology of Spodoptera litura on seven elite genotypes and integrated pest management modules for groundnut pests was undertaken at Main Agricultural Research Station (MARS), University of Agricultural Sciences, Dharwad, during Kharif, 2009 and results presented here under. 4.1 Field screening of groundnut genotypes Seven groundnut genotypes were screened against S. litura under artificial infestation in the field condition during 2009, rainy season. All the elite groundnut genotypes differed significantly in per cent defoliation and larval count (per m row). The damage ranged from 11.5 to 44.0 per cent in different genotypes. Maximum defoliation and number of larvae / m row were observed in the JL-24 (44.0% and 4.0) followed by GPBD-4 (33.5% and 3.5). The genotypes viz., Mutant-III (11.5% and 1.0) and ICGV- 86699 Tan (12.0% and 1.0) recorded minimum damage and less number of larvae / m row. The damage and number of larvae were moderate in GPBD-5 (23.5% and 2.0), ICGV86699 RED (23.5% and 2.0) and GPBD-6 (28.5% and 2.0) (Table 1). 4.1.1 Biology of Spodoptera litura on elite genotypes under laboratory conditions Spodoptera litura was reared on seven groundnut genotypes viz., JL-24, ICGV-86699 Red, GPBD- 5, ICGV-86699 Tan, GPBD- 6, Mutant III and GPBD- 4. Various parameters of growth and development of S. litura viz., number of days required for completion of each larval instar, prepupa, pupa, pre oviposition, oviposition, post oviposition and also larval weight, larval mortality at 5, 10 and 15 days after hatching, pupal weight, per cent survival on each variety, per cent adult emergence, adult longevity and total life cycle were studied. 4.1.1.1 Larval period During the entire larval period, the caterpillar moulted five times. Thus completed six larval instars. A brief description of each larval instar is presented below (Table 2). 4.1.1.1.1 First Instar Neonate larvae tiny, cylindrical and pale green with brown head. First abdominal segment has a pair of black spots. Three dorsal stripes were seen all along the body. Larvae congregated below the leaf at the site of egg laying. Scraped the epidermis which resulted in the papery leaf devoid of chlorophyll. The duration of first instar varied from 1.75 to 2.00 days in different genotypes. But there was no significant difference between the genotypes tested. 4.1.1.1.2 Second instar Except for increase in size, no marked change in body color was noticed. The larvae remained in congregation but moved little away from the previous site and scraped the chlorophyll resulting into thin papery leaf. The duration of second instar was significantly longer (3.83 days) on the genotypes, ICGV- 86699 Tan followed by Mutant III (3.50 days) than on other except GPBD-4 on which the second instar duration was least 2.42 days. 4.1.1.1.3 Third instar The larvae increased in size, turned pale green with brown head. A pair of black dots on first abdominal segment and three dorsal stripes all along the body were prominent. Larvae of this instar moved individually and punctured the leaflet.
Table 1: Performance of elite groundnut genotypes against Spodoptera litura damage under field condition during Kharif 2009 Sl. No. Genotypes Per cent defoliation 1 JL-24 (Susceptible check ) 44.0 a 2 ICGV86699 RED 23.5 d 3 GPBD-5 23.5 d 4 ICGV86699 TAN 12.0 e 5 GPBD-6 28.5 cd 6 MUTANT -III 11.5 e 7 GPBD-4 33.5 bc No. of larvae / m row 4.0 a 2.0 c 2.0 c 1.0 d 2.0 c 1.0 d 3.5 b S. Em ± 1.09 0.063 C.D. at 5% 3.31 0.019 C.V. (%) 13.0 8.53 In a column, means followed by the same alphabet do not differ significantly (P = 0.05) by DMRT
Page 1 and 2: SCREENING ELITE GENOTYPES AND IPM O
Page 3 and 4: CONTENTS Sl. No. Chapter Particular
Page 5 and 6: Figure No. LIST OF FIGURES Title 1.
Page 7 and 8: In some parts of the northern Karna
Page 9 and 10: mutants were systematically screene
Page 11 and 12: observed on Dwarf Mutant, the lowes
Page 13 and 14: Singh and Sachan (1991) recorded se
Page 15 and 16: Thontadarya and Nangia (1983) repor
Page 17 and 18: Monitoring with pheromone traps to
Page 19 and 20: 1. JL-24 (Susceptible check) 2. ICG
Page 21: Observations were recorded daily on
Page 25 and 26: Third instar duration was significa
Page 27 and 28: Table 3: Gain in larval weight and
Page 29 and 30: Table 4: Biological parameters of S
Page 31 and 32: Table 5: In vitro biology of Spodop
Page 33 and 34: sunflower and N. rileyi, foxtail mi
Page 35 and 36: Table 7: Leaf hoppers population in
Page 37 and 38: Table 8: Thysanoplusia orichalcea p
Page 39 and 40: Table 10: Spilarctia obliqua popula
Page 41 and 42: 4.2.4.2 50 days after sowing The de
Page 43 and 44: Table 13: The management of Spodopt
Page 45 and 46: The early instar larvae scraped the
Page 47 and 48: Module I Table 16: Natural enemy po
Page 49 and 50: Table 18: Natural enemy population
Page 51 and 52: Table 19: Economics of IPM modules
Page 53 and 54: Per cent defoliation 50 45 40 35 30
Page 55 and 56: Larval period and Total development
Page 57 and 58: Larval Larval weight weight (g) (g)
Page 59 and 60: 5.2.3 Defoliator population in thre
Page 61 and 62: Pest population 1600 1400 1200 1000
Page 63 and 64: Gross returns and Net returns (Rs./
Page 65 and 66: REFERENCES Agasimani, C. A., Ravish
Page 67 and 68: Kennedy, F. J. S., Rajamanickam. K.
Page 69 and 70: Prasad, M. N. R. and Gowda, M. V. C
Page 71 and 72: Tiwari, S. N., Rathore, Y. S. and B
Page 73:
SCREENING ELITE GENOTYPES AND IPM O
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screening elite genotypes and ipm of defoliators in groundnut

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