REPRODUCTIVE BEHAVIOUR AND PHYSIOLOGY OFTENEBRIO MOLITOR(COLEOPTERA: TENEBRIONIDAE): II. EGG DEVELOPMENT AND OVIPOSITION IN YOUNG FEMALES AND THE EFFECTS OF MATING

Abstract

AbstractVirgin females ofTenebrio molitorL. initiate vitellogenesis about 2 days after the imaginal moult. During the first 6 days after the imaginal moult, each female with males matured on the average 41 eggs and each virgin matured 29 eggs. Stimuli associated with copulation and(or) insemination apparently are not required to initiate vitellogenesis, but do enhance the rate of oocyte maturation. Mated females lay their first eggs on the fourth day and virgin females about 1 day later. After the sixth day, mated females matured oocytes at about the same rate as before this time, whereas oocyte production is almost completely inhibited in virgins. Mated females also laid about 7.5 times as many eggs and accumulated an average of 40% fewer eggs in their reproductive systems than virgins. It is suggested that stimuli associated with copulation and(or) insemination enhance oviposition per se in mated females, that the accumulation of eggs in the reproductive systems slows further development of oocytes in virgins, and that the inhibition of vitellogenesis in virgins occurs at, or soon after, the time the first gonadotropic cycle is completed. A system for classifying stages of oocyte maturation inT.molitoris described.