screening elite genotypes and ipm of defoliators in groundnut

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incidence of insect pests (Altieri et al., 1978). Kennedy and Raveendran (1989) reported that groundnut intercropped with pearl millet reduced the incidence of sucking pests substantially. Gavarra and Raros (1975) found more predatory spiders and predatory coccinellids in groundnut-maize cropping system than in sole crop of groundnut. The incidence of leaf hoppers, thrips and aphids were significantly reduced and population of predatory coccinellids was increased, when pearl millet intercropped with groundnut (Kennedy et al., 1990). Singh et al. (1991) conducted the field experiments in Delhi, in kharif season of 1987- 88, groundnut intercropped with red gram, green gram, sorghum and soybean. Among these intercrops, groundnut- sorghum intercropping reduced the incidence of leaf hoppers, thrips, bihar hairy caterpillar and tobacco caterpillar. Agasimani et al. (1993) studies conducted on the incidence of S. litura in the intercropping system indicated the maximum incidence noticed in groundnut + sunflower (4:1) intercropping whereas, the least incidence was noticed in groundnut + jower (4:1) intercropping. Patil (1993) reported among various intercrops, groundnut + sorghum recorded less S. litura damage. Whereas, groundnut + sunflower, groundnut + cotton and groundnut + chilli recorded more damage. Anonymous (2003) reported that among the two most important defoliators of groundnut, S. litura and H. armigera both prefer sunflower over groundnut for oviposition and feeding. Also, the newly hatched larvae of these pests disperse immediately from the egg site on the groundnut crop, while on the sunflower they stay for a week to ten days on the same leaf. These larvae make skeletons of sunflower leaves. At this stage, the damage on the trap crop (sunflower) is clearly visible, making it easier for the farmers to collect the leaves under attack for subsequent destruction of the larvae, and without chemical pesticides. Since groundnut is more vulnerable to defoliators before the flowering stage, it is necessary to protect this crop from defoliators during this phase. While the larvae feed and develops on the trap crop, the main crop (groundnut) escapes from the critical pest damage. The influence of straight fertilizers and organic manures on the groundnut sucking insect pests viz., jassid, Empoasca kerri Pruthi and aphid, Aphis craccivora Koch was studied in the field from 1994 to 1996 in sandy loam soils. These studies combined with other cultural practices like planting sunflower as a trap crop for S. litura and spraying of nuclear polyhedrosis virus (NPV) to reduce the incidence of S. litura (Rajasekhara, 2002). Theodore et al. (2008) reported that groundnut intercropped with maize reduced the incidence of aphids, thrips and pod borers and increased the population of predators and also yield. The higher numbers of predators in groundnut/maize could be due to the crop canopy providing more food and, shade to allow development of their different stages (eggs, larvae). 2.2.3 Natural enemies of Spodoptera litura According to Battu (1977), field collected larvae of S .litura were parasitized by the tachanid, Parasacrophaga misera (Wlk.) during October –November and by the ichneumonid, Campoletis sp. Both of these were first recorded from India. Joshi et al. (1979) reported that the natural enemies of S. litura on tobacoo in Andhra Pradesh. They collected eggs and larvae of S. litura from the field and reared in the laboratory for the emergence of parasites like Trichogramma australicum (Girault), Chelonus formosanus (Sonan), Apanteles sp, Strobliomyia aegyptia (Vill.), Blepherella setigera (Corti), Sarcophaga dux (Thoms.) and also predator like Ropalidia sp. Rao (1983) noticed that eggs of Corcyra cephalonica (Stainton) served as food for the larvae of Chrysopa scelestes (E.). These Chrysopa larvae were highly effective and fed voraciously on Corcyra eggs, Myzus persicae (Sulzer), Bemisia tabacci (Gennadius), eggs and just hatched larvae of S. litura.
Thontadarya and Nangia (1983) reported natural enemies of S. litura infesting soybean at Hebbal, Bangalore. Trichogramma chilonis Ishii, Brachmaria sp. and Bracon brevicornis (Wesmael) parasitized 32.5 per cent of the eggs, 3.4 per cent of the pupae and 16.3 per cent of the larvae, respectively. In addition, a nuclear polyhedrosis virus infected 21.4 per cent of the larvae. The list included Chrysopa sp, Coccinella sp and Scymnus sp preying on eggs or larvae of S. litura .According to the detailed studies conducted at IARI, New Delhi, Telenomus remus Nixon accepted 10 to 72 h old eggs of S. litura. Kulkarni (1989) recorded larval parasitoids emerged from S. litura in groundnut viz., a braconid, Bracon brevicornis Wesmael, an icneumonid, Campoletis chlorideae Uchidas and two tachinids, Campsilure concinnata Meigen, Peribaea orbatta Wiedemann. The occurrence and abundance of insect pests of groundnut and parasitoids, predators were studied in the field in Bangladesh in1984. 18 species of insect pests were recorded of which, Spilosoma obliqua, S. litura, Thysanoplusia orichalcea (F.) were dominant and one parasitoid, Gryon antestiae (Dodd) (Scelionidae), two predatory species Coccinella septempunctata (L.) and syrphids, Paragus sp. (Islam et al., 1983). Sridhar and Prasad (1996b) reported that larval parasitoids of S. litura, viz., Peribaea orbatta Wied. and Apanteles ruficrus Haliday caused 13.7 per cent and 8.2 per cent mortality, respectively in groundnut. Srivastava and Kushwaha (1995) reported that the parasitoid complex of S. litura consisted of an egg parasitoid, T. chilonis (31.8%) and nine larval parasitoids of which P. orbatta (14.3%) was the most abundant in cauliflower. Rao et al. (1990) observed that 5-10 per cent parasitisation of Charops obtusa (M.) and 80 per cent parasitisation of Apanteles africanus Cameron on S. litura in laboratory condition and these parasitoids were highly effective in tobacco nurseries. They also reported A. ruficrus was gregarious polyembryonic parasitoids parasite on S. litura in tobacco field. Similar trend was reported by Braune (1989). 2.2.4 Potentiality of Nomuraea rileyi (Farlow) Samson to Spodoptera litura (F.) Gopalkrishnan and Mohan (1990) reported that the field trials on N. rileyi against third instar larvae of S. litura on cabbage revealed that the fungus @ 1.2 × 10 8 conidia/ml caused 95 per cent mortality in 6 days after treatment. In the field, larval mortality of 52-60 per cent was observed at 12 days after spraying. The highest cumulative mortality of 88-97 per cent was observed after 19 days (Vimaladevi, 1994). In the laboratory, spraying the fungus at 10 8 , 10 9 , 10 10 and 10 11 conidia per litre of water against first instar larvae of S. litura resulted in cent per cent mortality within 5 days. The LC50 for third instar larvae was 2.89 × 10 10 at eight days. In the net house studies, initial mortality was observed at 7-8, days with an LC50 of 2.2×10 10 spores per litre. Larval mortality was initially observed in the field at nine days after spraying with the conidia. Even the lowest dose of 2 × 10 11 spores per litre resulted in significant cumulative larval mortality. There was no increase in mortality with increased dose (Vimaladevi, 1994).The conidial suspension sprayed on egg mass was found to cause 95.2 per cent mortality of neonate larvae (Gopalkrishnan and Mohan, 1991). Sridhar and Prasad (1996 a) reported about 86.9 per cent mortality of S. litura due to the entomopathogenic fungus on groundnut during 1991-1992 from Bapatla, a coastal region of Andhra Pradesh. According to Kulkarni (1999) seasonal incidence of N. rileyi to S. litura in groundnut, soybean and potato was noticed between 32 nd (Aug 1 st week) to 40 th (October 1st week) standard weeks. Among the three crops, maximum incidence was noticed in groundnut followed by soybean and least in potato. Patil (2000) studied on the entomopathogenic fungus, N. rileyi occurred in epizootic form on S. litura in groundnut during the rainy season. N. rileyi was found to be more effective
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: Singh and Sachan (1991) recorded se
Page 17 and 18: Monitoring with pheromone traps to
Page 19 and 20: 1. JL-24 (Susceptible check) 2. ICG
Page 21 and 22: Observations were recorded daily on
Page 23 and 24: Table 1: Performance of elite groun
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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