Role of the Corpus Allatum in the Control of Reproductive Diapause in the Male Blow Fly, Protophormia terraenovae

Abstract

Male Protophormia terraenovae showed a long-day photoperiodic response at 25°C with respect to the induction of mating behavior. Male adults transferred from long-day to short-day conditions at emergence showed no mating behavior. When the corpus allatum (CA) was removed 6–8 hr or 1 day after adult emergence under long-day conditions, about 60% of males showed mating behavior. When the CA was removed 2 days after adult emergence, however, most males showed mating behavior similarly to the intact controls. Application of a juvenile hormone analog increased the proportion of mating behavior from about 60 to 100% in males allatectomized 6–8 hr after adult emergence under long-day conditions, and from 0 to about 30% in intact males transferred to short-day conditions at adult emergence. Thus, the endocrine control of diapause in males is different from that in females in which the CA plays a predominant role. Male adults responded to photoperiod and showed mating behavior even after the CA was removed. The mating behavior is controlled also by a factor or factors other than the CA with respect to diapause.