Developmental physiology of corpora allata and accessory sex glands in the cecropia silkmoth

The storage of large quantities of juvenile hormone (JH) in adult male Cecropia silkmoths is dependent upon the combined activities of two organs: secretion by the corpora allata (CA) and accumulation by the accessory sex gland (ASG). We describe here some aspects of CA‐ASG development and physiology which lead to JH storage. The ASG were found to have completed development and had secreted the luminal materials before eclosion. After day 16 of adult development, the ASG were able to convert JH‐I acid to JH‐I and store the JH‐I. When incubated in vitro, the ASG showed a specificity for the uptake and storage of the three JH acids in the following order : JH‐I > JH‐II ≫ JH‐III. The CA of male and female larvae secreted JH‐I and JH‐II when incubated in vitro, whereas adult male CA secreted JH‐I acid and JH‐II acid. The total equivalent synthetic productivity of adult male CA was found to be considerably greater than that of adult female CA. When cultured in vivo during metamorphosis to the adult in hosts of the opposite sex, the male and female CA maintained their respective pattern of secretory activity. Thus, the CA appear to be programmed to express the sexually dimorphic activity prior to the initiation of adult development.