MALE ACCESSORY GLAND FACTORS ELICIT CHANGE FROM ‘VIRGIN’ TO ‘MATED’ BEHAVIOUR IN THE FEMALE CORN EARWORM MOTH HELICOVERPA ZEA

Abstract

After mating, the females of many species of moths become depleted of sex pheromone, calling behaviour is terminated, and they become transiently or permanently unreceptive to additional matings. In the corn earworm moth, Helicoverpa zea, we have found that the male accessory gland/duplex is required for evoking the post-mating depletion of sex pheromone but apparently not for the cessation of calling. The latter change requires the receipt of a spermatophore or a chemical messenger derived from non-accessory gland/duplex sources. Desalted extracts of combined accessory glands and duplexes caused a depletion of pheromone in injected females. Proteinaceous components in extracts purified by fractionation in cation-exchange cartridges and by reverse-phase high-performance liquid chromotography retain their pheromonostatic activity. In addition, this fractionated material shuts off calling behaviour and prevents mating in injected females, raising the possibility that redundant mechanisms exist in eliciting the different components of ‘mated’ behaviour.