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Baculoviruses were isolated from three major lepidopteran pests, Helicoverpa armigera, Spodoptera litura and Amsacta albistriga in the semi-arid tropics during natural epizootic conditions at ICRISAT fields, Patancheru, Andhra Pradesh, India. Biological, morphological and biochemical analysis identified these isolates as Nucleopolyhedroviruses (NPVs). Scanning electron microscopy of the occlusion bodies (OBs) purified from diseased larvae revealed polyhedral particles of size approximately 0.5-2.5 μm [Helicoverpa armigera Nucleopolyhedrovirus (HearNPV)], 0.9-2.92 μm [Spodoptera litura Nucleopolyhedrovirus (SpltNPV)] and 1.0-2.0 μm [Amsacta albistriga Nucleopolyhedrovirus (AmalNPV)] in diameter. Transmission electron microscopy of thin sections of OBs of the three isolates revealed up to 5-8 multiple bacilliform shaped particles packaged within a single viral envelope. The dimensions of these particles were 277.7 × 41.6 nm for HearNPV, 285.7 × 34.2 nm for SpltNPV and 228.5 × 22.8 nm for AmalNPV. Each of HearNPV and AmalNPV contained up to 6 nucleocapsids and SpltNPV contained up to 7 nucleocapsids per envelope. The estimated molecular weights of the purified OB (polyhedrin) protein of the three NPVs were 31.29-31.67 kDa. Virus yield (OBs/larva) was 5.18 ± 0.45 × 10(9) for HearNPV, 5.73 ± 0.17 × 10(9) for SpltNPV and 7.90 ± 0.54 × 10(9) for AmalNPV. The LC50 values of various NPVs against 2nd and 3rd instar larvae indicated 2.30 × 10(4) and 1.5 × 10(5) OBs/ml for HearNPV, 3.5 × 10(4) and 2.4 × 10(5) OBs/ml for SpltNPV and 5.6 × 10(4) and 3.96 × 10(5) OBs/ml for AmalNPV. The lethal time required to cause 50% mortality (LT50) for these three species were also defined. This study has shown that the NPVs infecting three major lepidopteran pests in India are multiple NPVs, and they have good potential to use as biocontrol agents against these important pests.

A review of field research conducted at the ICRISAT in collaboration with national partners to monitor the insecticide residues on food crops (rice, chickpea, maize, pigeon pea) and vegetables and the recent studies by other researchers in this field revealed the presence of residues of selected pesticides on crops. These include monocrotophos, chlorpyrifos, endosulfan, and cypermethrin. Only 3 % of the rice had beta endosulfan residues, while 35 % of tomato and 56 % brinjal had residues of these insecticides; however, only 4 % of the samples had residues above the maximum residue limits (MRLs). The crop samples analyzed (56) for pesticide residues in 15 contact (nonchemical pesticide group of 41 farmers) and 5 noncontact (15 samples) villages revealed the presence of pesticide residues in 21 samples above 0.001 ppm, except for two Dolichos bean and tomato samples which had residues of monocrotophos and chlorpyrifos above MRL. Though the residues in pulses were observed at harvest, they were below detectable levels after processing, i.e., thrashing and splitting the seed into dhal, indicating their safety in food chain; however, their haulms had insecticide residues. Fields under integrated pest management (IPM) showed substantial reduction in pesticide use across crops, which reflected in the occurrence of low residues. Twenty percent of brinjal and tomato samples had residues compared to 47 % in non-IPM fields. Though the contamination levels in crops in IPM and non-IPM fields indicated substantial differences, the residue concentrations were below MRLs indicating safety to beneficial arthropods.

Lepidopteran insect pest species cause heavy damage to the crop yield annually around the globe. Baculoviruses, the nucleopolyhedroviruses and the granuloviruses, act as natural regulators of pest populations including lepidopteran pests, and their potential to be employed as insecticides is well reported. Baculovirus-based insecticides are safe to animal and human health and lack toxic residues. In the present chapter, a detailed review on the isolation, characterization, mass production techniques, diagnostic and quality control tests of these viruses, and the issues related with commercialization of baculovirus-based products is presented. Their high compatibility with other pest control strategies making them a potential candidate for use in integrated pest management is also discussed.

Insect pests are considered the major hurdle in enhancing the production and productivity of any farming system. The use of conventional synthetic pesticides has led to the emergence of pesticide-resistant insects, environmental pollution, and negative effects on natural enemies, which have caused an ecological imbalance of the predator-prey ratio and human health hazards; therefore, eco-friendly alternative strategies are required. The plant kingdom, a rich repertoire of secondary metabolites, can be tapped as an alternative for insect pest management strategies. A number of plants have been documented to have insecticidal properties against various orders of insects in vitro by acting as antifeedants, repellents, sterilant and oviposition deterrents, etc. However, only a few plant compounds are applicable at the field level or presently commercialised. Here, we have provided an overview of the broad-spectrum insecticidal activity of plant compounds from neem, Annona, Pongamia, and Jatropha. Additionally, the impact of medicinal plants, herbs, spices, and essential oils has been reviewed briefly.

he occurrence of peanut bud necrosis (PBN) disease in India was first reported in 1968. The high incidence of PBN disease during the 1960s coincided with large-scale imports of the peanut cultivars Asiria Mwitundae and Spanish Improved, both of which are highly susceptible to PBN. Since then, a number of reports have been published in India describing bud necrosis under at least seven different names (Reddy 1988). Crop losses due to PBN have been estimated at USD89 million per year in India during 1976–1986. The disease is also currently recognized as economically important in Nepal (Sharma 1996), in Sri Lanka, and in Thailand (Wongkaew 1995). The causal agent of PBN was originally reported as tomato spotted wilt virus (TSWV) (Ghanekar et al. 1979). Since then, methods to purify the causal virus of PBN have been developed, which facilitated the production of good quality antisera. On the basis of serological relationships, some physicochemical properties, and thrips transmission, it was shown that the causal virus of PBN in India was a distinct tospovirus that was named peanut bud necrosis virus (PBNV, Reddy et al. 1992). These results were subsequently confirmed by Adam et al. (1993). Later, monoclonal antibodies (MAbs) have been produced against the nucleocapsid (N) protein of PBNV (Poul et al. 1992). Antibodies from nine clones failed to react with a TSWV-lettuce (TSWV-L) isolate and with an impatiens necrotic spot virus (INSV) by triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) (coating of PBNV polyclonal antiserum, addition of antigen followed by addition of MAbs and antimouse IgGs conjugated to alkaline phosphatase). Of 16 MAbs produced against TSWV-L (Hsu et al. 1990), 12 H5 Al (f), 12 H5 H5 (1

Potability of drinking water from various sources at the campus of International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Andhra Pradesh, India had been assessed for 17 years (1994 to 2010). All four sources of drinking water at ICRISAT, including Manjeera water (Municipal corporation supplied drinking water), borewell 1, borewell 2 and ICRISAT water (mixture of both Manjeera as well as borewells after treatment), were tested for their potability once in two months by most probable number (MPN) method. The results indicated that water from borewells were not safe to drink without treatment as Escherichia coli was found in 10 and 12 years out of 17 tested years for bore wells 1 and 2, respectively. Manjeera water samples were also found unsafe in two out of the 17 years, whereas ICRISAT water was found safe to drink throughout the study period. This study indicated that even deep borewells (of about 135 ft) can get contaminated, and its water is not safe to drink without treatment, and an additional treatment of municipal water supply is required in order to have safe drinking water. Keywords: Potability, drinking water, Escherichia coli , borewell water, municipal water

Pesticide residue monitoring was taken up at Kothapally and Enkepally villages of Ranga Reddy district, Andhra Pradesh in food crops (rice, maize, pigeonpea), vegetables (tomato and brinjal), cotton besides soil and water during 2008-2009 seasons. Of the 80 food crop and cotton samples, only two rice grain samples (3 %) showed beta endosulfan residues and two (3 %) out of 80 soil samples of food crops and cotton showed alpha and beta endosulfan residues. Out of 75 tomato samples, 26 (35 %) were contaminated and 4 % had residues above maximum residue limit (MRLs). Out of the 50 soil samples from tomato fields, 13 (26 %) contained residues. Among the 80 brinjal samples, 46 (56 %) contained residues and 4 % of samples had residues above MRLs. Only 13 % of the soil samples from brinjal fields were contaminated. Water samples found free from residues. In general the incidence of residues was below MRL in food crops.

Published information was used to compile a summary of natural enemies (parasitoids, predators and diseases) reported attacking Spodoptera litura (F) under field conditions. Species (71) of insect parasitoids in seven families of Hymenoptera and two families of Diptera were listed as parasitoids of different stages of S. litura. Predatory insects (36) belonging to 14 families and 12 species of spiders from six families have been reported to feed on this species. Four protozoan, four fungal, seven bacterial, four each of viral and nematode species were also reported to be the pathogens of this species. Published information suggested that periodic releases of large number of egg parasites could help in suppressing populations of this pest. There is a considerable scope for increased attention to the role of natural enemies as component of integrated pest management programmes of S. litura.

Natural enemies of the groundnut leaf miner,Aproaerema modicella (Deventer), were studied at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) located near Hyderabad in peninsular India. Hymenopterous parasitoids attacking leaf miner larvae were the most important group of natural enemies. Nine primary and eight secondary parasitoids emerged from host larvae, and killed up to 50% of the leaf miner larvae sampled. The trophic relationships between primary and secondary parasitoids are incompletely understood. The influence of pathogens of this species is reported for the first time. These pathogens killed up to 30% of the leaf miner larvae. The combined effects of all mortality agents killed up to 95% of the leaf miner larvae per sample period. However, use of insecticides in sprayed plots reduced the efficacy of parasitoids. The impact of predators on larval populations was not studied and may explain underestimates of leaf miner mortality rates.

The Integrated Pest Management (IPM) Programme under development at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) calls for a proper monitoring system. Experiments conducted in groundnut fields at ICRISAT Center near Hyderabad, in peninsular India, to establish the optimum height for pheromone traps to monitor Spodoptera lituta (F), indicated that the male flight pattern changes considerably during the cropping period. During the seedling stage (sowing to 6 weeks), most moths were caught at 0.5 and 1.0 m. In the initial growth phase (7–11 weeks), the traps at 4.0 m caught most moths. During the optimum growth phase (12th week to harvest) of the crop the traps at 1.0 m height trapped most moths. After harvest, the traps at 4.0 m again recorded the highest catch. These data are interpreted in terms of the migration pattern of S. litura moths during the crop season. We suggest monitoring this species, using 1 m height traps Males were found to be more active around 0300 hr, with a small peak after sunset (2000 hr). Irrespective of season, the peak flight activity of this species was around 0300 hr in groundnut fields

SUMMARY The behaviour, development and reproductive capacity of Aphis craccivora, vector of a number of groundnut viruses, are compared on a range of susceptible and resistant genotypes. Field trials demonstrated no significant difference between genotypes in the rate of arrival of alates, but population development was slower, and subsequent population decline faster, on the genotype EC 36892 (ICG 5240). Behavioural studies in the screenhouse, likewise showed no inhibition to alighting onto EC 36892 though choice tests demonstrated a significant redistribution of the population in favour of the susceptible genotype TMV 2 (ICG 221) over the following 10 h. In clip cage experiments, development was faster and nymphal numbers were higher on the genotype TMV 2 compared to EC 36892.

Bud necrosis disease (BND), caused by peanut bud necrosis virus (PBNV) is an important disease of peanut (Arachis hypogaea L.) in India. Studies with Thrips palmi, Frankliniella schultzei and Scirtothrips dorsalis showed that only T. palmi transmitted PBNV. T. palmi acquired the virus as larvae, requiring a 5-min acquisition period, but only transmitted it as adults. Adults needed an inoculation feeding period of > 1 h to transmit, and the majority transmitted the virus throughout their life. In field situations, a virus-susceptible peanut genotype had higher densities of T. palmi than resistant genotypes. In peanuts, S. dorsalis was the dominant foliar species, T. palmi was on foliage and flowers, and F. schultzei was mostly on flowers. Several common weed species in peanut were infected with PBNV and were colonized by T. palmi.

Participatory rural appraisal was undertaken in 70 villages in India and Nepal, covering 1185 farmers to generate baseline information on the current plant protection practices. The study revealed that 93% of the farmers in India and 90% in Nepal had adopted chemical control for the management of various insect pests in different crops; however, less than 20% of the farmers expressed confidence on their efficacy. In India, 52% of farmers get their plant protection advice from pesticide dealers, while in Nepal, the majority of the farmers (69%) make their plant protection decisions through agricultural officers. A majority of the farmers (73% in India and 86% in Nepal) initiate the plant protection based on the first appearance of the pest, irrespective of their population, crop stage and their damage relationships. About 50% of the farmers in India and 20% in Nepal were not using any protective clothing while spraying. Health problems associated with the application of plant protection chemicals were reported by farmers. The cost of plant protection on various crops ranged from 7 to 40% of the total crop production cost. Though integrated pest management (IPM) has been advocated for the past two decades, only 32% in India and 20% in Nepal were aware of IPM practices. IPM implementation in selected villages brought a 20-65% reduction in pesticide use in different crops. The vegetable samples analysed for pesticide residues revealed the presence of residues.

The spotted pod borer Maruca vitrata (Geyer) is known for its economic importance throughout its geographical distribution because of its destructive nature to reproductive parts of several grain legume crops including pigeonpea. In view of the importance of the pest, the present study was carried out on the association of different morpho-chemical traits with resistance/susceptibility to M. vitrata at the International Crops Research Institute for the Semi-Arid Tropics, Patancheru, India. Trichome length and density, sugars, proteins and phenols were found to be associated with resistance to M. vitrata in short-duration pigeonpea genotypes. Pod damage by M. vitrata on different short-duration pigeonpea genotypes in the field ranged from 5.8 to 68%. Laboratory studies showed less consumption of food and reduced larval and pupal weights of M. vitrata when reared on the resistant genotypes ICPL 98003 and ICPL 98008 indicating antibiosis effects of the genotypes. Trichome density on upper and lower surfaces of the leaf (390 and 452/9 mm ), and length (3.5 mm) and trichome density (442/9 mm2) and length (5.9 mm) on pods were found positively correlated with the resistant genotype ICPL 98003. High sugar content in flowers (22%) and pods (10.6%) was responsible for the susceptibility of ICPL 88034, while high phenol concentration in flowers (6.5%) and pods (9.3%) in ICPL 98003 was responsible for resistance. Protein content in pods was significantly higher (25.5%) in susceptible ICPL 88034 when compared with resistant ICPL 98003 (16.5%). Based on these results, ICPL 98003 and ICPL 98008 were categorized as highly resistant and ICPL 98012 as moderately resistant. This paper discusses the physico-chemical traits associated with resistance to M. vitrata in short-duration pigeonpea genotypes.

Neem products are often perceived as harmless to natural enemies, pollinators and other non-target organisms. For this reason, several integrated pest management (IPM) programmes have adopted neem as one of the prime components. This study revealed toxic effects of neem on soil-inhabiting and aerial natural enemies in chickpea to an extent of 41 and 29% population reduction, respectively, compared with 63 and 51% when using a conventional insecticide (endosulfan). Neem also affected the parasitization of Helicoverpa armigera (Hubner) larvae by Campoletis chlorideae Uchida up to 20%. The natural enemy population started building up from the vegetative phase and reached their peak during the reproductive phase, and there was a gradual decline from pod formation to pre-harvest phases of the crop. Adapting the currently used IPM system in chickpea using neem during the vegetative phase, followed by an application of Helicoverpa nuclear polyhedrosis virus (HNPV) at flowering and need-based application(s) of chitin inhibitors like novaluron or flufenoxuron instead of endosulfan during pod formation would strongly augment natural enemy populations. This paper discusses the relative toxicity of neem and other IPM components on soil-inhabiting and aerial natural enemies in the chickpea ecosystem.

Four elite peanut (Arachis hypogaea L.) germplasm lines, ICGV 86252 (Reg. no. GP-69, P1 585001), ICGV 86393 (Reg. no. GP-70, P1 585002), ICGV 86455 (Reg. no. GP-71, P1 585003), and ICGV 86462 (Reg. no. GP-72, P1 585004), resistant to jassid (Empoasca kerri Pruthi), were developed at the Asia Center of the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, India. They were released in 1993 by the ICRISAT Plant Materials Identification Committee.

ICGV 86031 (Reg. no. GP-58, PI no. 561917) is a spanishtype peanut (Arachis hypogaea L. subsp. fastigiata Waldron var. vulgaris Hartz) developed at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, India. It was released in 1991 by the Plant Materials Identification Committee of ICRISAT because of its resistance to thrips (Thripspalmi Karny), jassid (Empoasca kerri Pruthi), spodoptera [Spodoptera litura (Fabricius)], groundnut leaf miner (Aproaerema modicella Deventer) and bud necrosis virus (BNV), which causes bud necrosis disease (END) in peanut. ICGV 86031 has also been found to be photoperiod insensitive and resistant to iron deficiency chlorosis (4).

Developmental thresholds and thermal requirements for different stages of Spodoptera litura (F.) fed on groundnut leaves were determined under constant laboratory conditions and in the field. An average of 64 degree-days (DD) above a threshold of 8°C was required from oviposition to egg hatch; the larval period required 303 DD and pupal stage 155 DD above a 10°C threshold; females needed 29 DD above a 10.8°C threshold from emergence to oviposition. Fifth and sixth instars accounted for about 50%of the total larval requirement under laboratory and field conditions. The response of various stages of S. litura to temperatures under constant laboratory conditions was similar to that under field conditions. The upper developmental threshold temperature of all stages was 37°C; 40°C was lethal.