The effects of preimaginal treatments with organo-phosporus insecticides on the life history of the egg parasitoid telenomus busseolae (Hymenoptera:Scelionidae)

Maize is one of most widely cultivated crop plants in Turkey. Maize is under attack of Mediterranean stem borer Sesamia nonagrioides (Lepidoptera: Noctuidae) throughout growing season of both main (first) and second crop. In this study, lethal and sublethal effects of two commonly used organic phosphorous insecticides, Prophenophos and Chlorpyriphos Ethyl on two preimaginal stages of one of the most important natural enemies of S. nonagrioides, the egg parasitoid, Telenomus busseolae (Hymenoptera: Scelionidae) were investigated. The insecticides, Prophenophos and Chlorpyriphos Ethyl adversely affected emergence rate, percentage parasitism and sex ratio of the parasitoid after insecticide exposure at both preimaginal stages two days (larval stage) and eight days (pupal stage) old. The adverse effect of tested insecticides varied between two preimaginal stages. This study elucidated that using Prophenophos 0.1 ml (suggested field dose), 0.05 ml, 0.025 ml, 0.0125 ml/l and Chlorpyriphos Ethyl 0.18 ml (suggested field dose), 0.09 ml, 0.045 ml ve 0.025 ml/l in integrated pest management may be inconvenient for T. busseolae.