LIFE-STAGE SPECIFIC TOXICITY OF INSECTICIDES TO PARASITOIDS OF LIRIOMYZA-TRIFOLII (BURGESS) (DIPTERA, AGROMYZIDAE)

Adults, larvae and pupae of Diglyphus intermedius (Girault) and Neochr ysocharis punctiventris (Crawford), (Hymenoptera: Eulophidae), parasit oids of the leaf-miner Liriomyza trifolii (Burgess) (Diptera: Agromyzi dae), were exposed to methomyl, permethrin, methamidophos, thiodicarb, endosulfan, fenvalerate, abamectin, Bacillus thuringiensis var. kurst aki and cyromazine in the laboratory. Permethrin and methomyl were hig hly toxic to all life stages of both parasitoids while methamidophos w as highly toxic to adults but was less toxic to larvae and pupae. Endo sulfan tended to be highly toxic to N. punctiventris but less toxic to D. intermedius. Thiodicarb, fenvalerate and abamectin tended to be le ss detrimental to at least some life stages of both parasitoids compar ed with methomyl, permethrin, methamidophos or endosulfan. B. thuringi ensis and cyromazine generally were the least toxic to all life stages , especially of D. intermedius. The implications for field identificat ion of leaf-miner parasitoids in making decisions regarding insecticid e use within pest management programmes are discussed.