EFFECT OF BACILLUS-THURINGIENSIS ENDOTOXIN ON APANTELES-LITAE NIXON AND BRACON-INSTABILIS MARSH (HYM, BRACONIDAE), 2 PARASITOIDS OF THE POTATO-TUBER MOTH PHTHORIMIA-OPERCULELLA ZELLER (LEP, GELISHIIDAE)

Treatment of the host larvae, P. operculella, with B. thuringiensis di d not change their susceptibility to being parasitized by either B. in stabilis or A. litae. The longevity of adults of both parasitoids, as well as their egg production, were not markedly affected as a result o f the treatment, while the duration of immature stages was prolonged. Also, emergence of the adult parasitoids was significantly reduced. Th e longevity of emerged adult parasitoids was significantly shortened w hen fed on honey containing B. thuringiensis and the fertility of the resultant females was significantly reduced.