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 2 ), and length (3.5 mm) and trichome density (442/9 mm 2 ) 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.

A study of the influence of the dcnsity of larval Hrlico\~crl>tr ontti,qc~rtr (instars 44)) o n the sccii yicld of chickpca plants growing in largc cagca indicated th;~t one larva per plilnt wi~s ;I criticill dcnsity as far ;IS ccononiic injury levels arc conccrncd. The results indici~tcd that larval feeding activity during the first 2 weeks of flowering had no cffcct on yield. Tticrc was also no cvidcncc olcornl,cnsiltory growth I'ollowing inscct attnck during the flowering stagc. 'l'hcsc ilats were iidoptcd to set i~ctitrn thresholds in a li~rpc (0.8 ha) field experiment that was dcsigncd to invcstiyitc the economics of insccticidc ;~pplici~tion in the contcxt of ; I I~ on-farm chickpea enterprise. Tlic field was m;lnagcd with bullock-drawn implcnicnts ;lniI hand labour. lnsccticidcs were applicd to tlircc v;~rictics-Annigcri (i~n iriscct-susccptihlc I;~ndrircc). ICCC 37 (a recently rclcascd variety) and ICC 506 (an insect-resistant landrace)-weekly, not ;it all (controls) ?nd whcn the larv:~l dcnsity cxcccdcd 0.5 or 2.0 per plant. Economic pilritnictcrs wcrc assembled from villagc and local market records. tielic,ovt,rp(~ had a niarkcci cffcct on the yield of the two pest-susccptihlc varictics, both of which would havc mildc ;I loss in the contcxt of a chickpcit cntcrpriac unless protected by insccticidcs. II~21ic~ove~rpc~-resistunt I('(' 500 tiid not achieve ah high a yicld ;IS thc other two varictics whcn treated with insccticidcs hut tiid 'ni;rkc ;I profit' whcn no insccticidc was applied. The rclntionship bctwccn yicld and inscct days was virtually identical for Annigcri and ICY('(' 37. The latter needed five insccticidc applications to maximize yicld and the fornicr four. The rcli~tionships bctwccn inscct day summations (integrals of population curves) for cggs, and sn~all iind largc larvac. suggested that cggs were unilcrsamplcd and were riot suitable as an indicator for irisccticidc i~pplici~tions. Thc dcnsity of small larvac, although probi~hly undcrsamplcd, was a suitable indication of Ihc damage likcly to be caused by the Ii~rgc larvac thcy would develop into. A set of inscct day sunimationa indicates whcn insccticidcs in the currcnt price range (Rs30(), 4(M) or 850 ha I) ncctl to be i~pplid. 'I'hc thresholds were vcrificti in ncighbouring fields. Thrcc insccticidc applications during the following season rc*ultcd in a greater than threefold incrcasc in yicld (from 0.65 to 2.2 t ha I) .

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 (Hü bner) 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.

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.