S.LingappaS.S.Navi2016-11-022016-11-022009http://krishikosh.egranth.ac.in/handle/1/83522Micromus timidus accepted nine aphid species and a psyllid as host. Leaves, open bolls and cotton thread served as oviposition substrates. Full grown larva pupated in double layered cocoon in counseled places. Aphis gossypii and Melanaphis sacchari found to be most suitable hosts as growth, development reproductive traits and feeding potential were in favour. Egg to adult and egg to egg duration was shortest on A. craccivora followed by M. sacchari. Both larva and adult of M. timidus consumed higher number of A. gossypii and M. sacchari as most palatable food sources. Morphometry of mouth and body parts were also recorded. Rearing of Micromus igorotus on A. gossypii and C. lanigera for five generations did lower fecundity slightly but not other traits. Reduction in survivability of egg, larva and adult was evident. Micromus igorotus @ 1,000 adults/ha outperformed in reducing cotton aphid population. Five pairs of M. timidus adults/plant reduced the cotton aphid population. Five pairs of M. timidus adults/plant reduced the cotton aphid population effectively with higher predatory recovery. On tobacco, 20,000 to 25,000 M. igorotus adults/ha reduced aphid population and increased yield by 46.6 and 56.8 per cent. Release of five pairs of M. timidus adults/plant was also effective. Emamectin benzoate was highly toxic to all stages of M. igorotus and M. timidus and thiodicarb was least toxic to eggs and larva. Profenophos at recommended field concentration persisted at greater level to inflect above 90 per cent mortality to grubs up to 7 days and retained toxicity for 30 days. The order of persistent toxicity was profenophos>thiomethoxam >methomyl>imidacloprid>novaluron>thiodicarb>emamectinbenzoate>spinosad> indoxacarb. Micromus igorotus eggs were devoured by C. carnea grubs, C. sexmaculata grubs and adults and syrphid maggots under free choice in the presence of aphid. While, M. igorotus did not feed on any stage of these predators.Agricultural EntomologyThesis