Role of brain, ventral nerve cord, and corpora cardiaca-corpora allata complex in the reproductive behavior of female tobacco budworm (Lepidoptera: Noctuidae)

Abstract

Various surgical treatments were used to determine the role of the brain, ventral nerve cord (VNC), and corpora cardiaca-corpora allata complex in the reproductive behavior of Heliothis virescens (F.). VNC-transected females mated successfully and exhibited increased egg production after mating, suggesting that an intact VNC is not required for calling, sex pheromone emission, mating, or mating-induced oögenesis. The patterns of increase in egg production in decapitated, virgin females and mated, decapitated females were similar. Allatectomized females called less overall than did the others, but all females called and were able to mate with males. The allatectomized, virgin females produced <20 eggs in total, whereas allatectomized females mated to normal males produced ≈90 eggs. Mated females decapitated immediately after uncoupling produced nearly 3 times as many eggs as decapitated, virgin females. Females decapitated at 6 h after uncoupling showed a further significant stimulation in egg maturation. These findings suggest that the male transfers some factor that, by itself, stimulates oögenesis.