Lethal and sub lethal effects of fresh and old residues of azadirachtin, spinosad, var. ( var. ), and deltamethrin, were evaluated at their recommended field doses against adult and immature stages of under conditions. The experiments were carried out at the Entomology section of Division of Crop Protection, ICAR Research Complex for NEH region, Umiam, Meghalaya, in 2012-2013. The effects of different pesticides were determined by bioassays using the residual film method, the diet contamination method, the pupal dip method and the topical application technique. The four pesticides were found harmful to adult after ingestion, however surface contact bioassays revealed that var. was the least toxic pesticide. Except var., other three pesticides were found harmful also to the immature stages of and significantly affected parasitism potential, adult emergence, longevity of adults, and sex ratio of the progeny. Deltamethrin and azadirachtin were the most harmful, even after 15 days of application. Spinosad was found to be relatively safe to after 15 days of application. As appeared to be the least toxic pesticide for, it could be used for the management of severe infestations of lepidopteran pests in cruciferous ecosystems. If essential, spinosad may be used 15 days after parasitoid release, thus minimizing the chances of parasitoid exposure.