DIAPAUSE AVERSION IN THE ADULT OLIVE FRUIT-FLY THROUGH EFFECTS OF THE HOST FRUIT, BACTERIA, AND ADULT DIET

Adult diapause of Bactrocera oleae (Gmelin) lasted for 28 days when the preimaginal stages developed at a photoperiod of 12:12 (L:D) h and 19 +/- 1-degrees-C and the adults were maintained at 16:8 (L:D) h and 26 +/- 1-degrees-C and fed on a sucrose diet. This reproductive immaturity was averted in most flies when the adult females had access to olive fruits, surface sterilized or not, or were fed a diet containing yeast hydrolyzate. Immaturity was also averted in part of the population when a bacterial culture from the fly's esophageal diverticulum was added to the sucrose diet. Immaturity persisted in the presence of olive leaves, in the presence of olive fruits when streptomycin was added to the adult sucrose diet, and when bacteria isolated from olive fruits were added to the sucrose diet.