Efficacy of Three Insecticides Applied in Three Regimes Against Insect - Pests of Cowpea

Three insecticides - endosulfan (0.08%), monocrotophos (0.04%) and phos-phamidon (0.04%) were applied in three spraying regimes - single spray after 45 days of sowing (St>, single spray after 50 days of sowing (S2) and two sprays after 50 and 60 days of sowing (S3) against insect - pests of cowpea during Kharif 1982 and 1983 at the Indian Grassland and Fodder Research Institute, Jhansi (U.P.). The results indicated that maximum control of leaf hoppers (Empoasca kerri Pruthi) and flower nibblers (Mylabris pustulata Th. and Catochrysops cnejus Fabr.) was afforded by monocrotophos whereas damaging activity of defoliators (Pagria signata Motsch, Plusia nigrisigna Wlk., Spodoptera litura Fabr., Colemania sphenarioides Bol., Chrotogonus trachypterus Blanch. and Atractomorpha crenulata crenulata Fabr.) was controlled better by endosulfan applied 50 days after sowing. However, maximum seed yield was obtained from plots treated with monocrotophos at 50 days age of crop.