EFFECTS OF BACILLUS-THURINGIENSIS ON PARASITOIDS OF THE OLIVE MOTH, PRAYS-OLEAE BERN - (LEP, YPONOMEUTIDAE)

Field-collected larvae of the anthophagous generation of Prays oleae w ere sprayed with Foray 64B, a commercial formulation of Bacillus thuri ngiensis. The larvae were then reared in the laboratory, to determine whether the survival of larval parasitoids was adversely affected. The effects of Bt on adult parasitoids was also examined by exposing the insects to various diets including one containing the bacterium. Treat ment of hosts with Bt was found to affect larval parasitoids adversely by increasing mortality of larval parasitoids within hosts surviving Bt treatment and by reducing the body size of adult parasitoids. The l ongevity of adult parasitoids was not adversely affected by Bt in the diet. The potential importance of Bt-induced mortality of parasitoid l arvae is discussed in relation to biological control in IPM programmes .