Effect of insecticides on Trichogramma chilonis L., egg parasitoid of large cabbage moth, Crocidolomia pavonana F.

Abstract

The study was carried out to examine the effects of key insecticides against Trichogramma chilonis parasitism of large cabbage moth (LCM). Three days after spraying with AttackTM, OrtheneTM and EntrustTM (permethrin + pirimiphos-methyl, acephate and spinosad), no parasitism of LCM eggs occurred. After 3 days of Bacillus thuringiensis (Bt) treatment, parasitism of LCM egg mass was 100 %, which is the same as the control. No parasitism of the egg mass occurred after spraying with either AttackTM or OrtheneTM. The percentage of parasitised LCM eggs after Bt treatment was 13.48; the control showed the highest parasitism of LCM eggs (58.13 %). The mortality of T. chilonis adults (in descending order) due to the insecticides after 15 hours was Entrust, Attack, Orthene and Bt. The result suggests that Bt could be included in Integrated Pest Management Programmes that depend on T. chilonis parasitism of LCM eggs and T. chilonis activity.