LABORATORY TEST METHOD TO EVALUATE THE EFFECT OF 31 PESTICIDES ON THEPREDATORY BUG, ORIUS-LAEVIGATUS (HET, ANTHOCORIDAE)

A laboratory test method was developed to evaluate the pesticide toxic ity on the predatory bug Orius laevigatus (Fieber). Newly hatched firs t-instar nymphs of O. laevigatus were exposed to spray deposits of pes ticides that were sprayed on the glass plates of a drum cell at the ma nufacturer's recommended maximum dosage. Nymphal mortality and oviposi tion of surviving adults were recorded. Test results of various (31) c ommonly used pesticides (insecticides, insecticides/acaricides, acaric ides and fungicides) are presented and discussed in accord with the cl assification of the IOBC/WPRS Working Group ''Pesticides and Beneficia l Organisms''. Most fungicides had no toxic effect on nymphal developm ent and egg-laying of surviving adults. The acaricides tested had vari able toxicity on the predatory bug, while some insect growth regulator s, such as the benzoylphenyl urea were very toxic. Otherwise, the ecdy sone agonist tebufenozide and azadirachtin were not harmful for nympha l development and oviposition.