EFFECTS OF MATING AND ACCESSORY-GLAND INJECTIONS ON OLFACTORY-MEDIATED BEHAVIOR IN THE FEMALE MEDITERRANEAN FRUIT-FLY, CERATITIS-CAPITATA

The female Mediterranean fruit fly, Ceratitis capitata, exhibits a pre ferential switch in certain olfactory-mediated behaviors as a result o f mating. Unmated, laboratory-reared, virgin females chose the odor of male-produced pheromone over host fruit odor (guava) in a dual-choice flight tunnel bioassay. Females continued to preferentially respond t o the male pheromone for several weeks if not allowed to mate. Mated f emales chose the host fruit: odor over the male-produced pheromone and deposited significantly greater amounts of fertile eggs if given tbe opportunity. Virgin females injected with accessory gland fluid (AGF) from sexually mature males will ''switch'' their response from choosin g the pheromone odor to choosing host fruit odor in the flight tunnel bioassay and exhibit egg-laying behavior typical of mated females. Sig nificant differences in the number of female landings, time on the sou rce (sphere) and number of eggs laid occurred when females were inject ed with AGF levels of 0.2 male equivalents or greater. Thus AGFs assoc iated with sexually mature males contain factors that appear to influe nce olfactory-mediated flight behavior.