not in Young Four synthetic insecticides, viz. malathion, fenvalerate, fipronil and cypermethrin, a neem formulation (Achook) and a combination treatment of Bacillus thuringiensis Berliner with cypermethrin were evaluated for efficacy against the diamondback moth, Plutella xylostella (Linn.), on cauliflower crop during 2002, and on two important parasitoids of this species at Palampur, Himachal Pradesh. Malathion and lipronil caused higher mortality of the pest than rest of the insecticides. However, cypermethrin, cypemiethrin + B. thuringiensis and Achook were relatively safe to the P. xylostella parasitoids, namely Diadegma fenestrale (Holmgren) and Cotesia plutellae (Kurdyumov), causing 29.16, 33.33 and 35.41 per cent decrease in parasitisation against >45 per cent parasitism in other treatments. BR Nutrition. Diet. Parasites diseases and disorders. Parasites. Insect parasites. Hosts. Insect hosts. Abiotic factors. Chemical factors. Land zones. Oriental region. Eurasia. Asia. India. Plutella xylostella (Plutellidae): Host; Cotesia plutellae (Braconidae): Parasite; Diadegma fenestrale (Ichneumonidae): Parasite. Cotesia plutellae, Diadegma fenestrale: Lepidopteran hosts, Plutella xylostella, Non-target effects of insecticides and bio-pesticides on parasitoid complex, cauliflower crops, Fertilizers and pesticides, Insecticides and bio-pesticides, Himachal Pradesh, Palampur; Plutella xylostella: Food plants, Cauliflower, Hymenopteran parasites, Diadegma fenestrale and Cotesia plutellae, Non-target effects of insecticides and bio-pesticides on parasitoid complex, cauliflower crops, Fertilizers and pesticides, Insecticides and bio-pesticides, Himachal Pradesh, Palampur. ST Insecta, Lepidoptera, Glossata, Heteroneura, Yponomeutoidea, Plutellidae; Insecta, Hymenoptera, Apocrita, Terebrantia, Ichneumonoidea, Braconidae; Insecta, Hymenoptera, Apocrita, Terebrantia, Ichneumonoidea, Ichneumonidae. Arthropods; Hymenopterans; Insects; Invertebrates; Lepidopterans. none