On the control of a sexual character in the aphidAcyrthosiphon pisum: the sex pheromone glands of oviparous females

Abstract

In Acyrthosiphon pisum the tibial plaques, through which sexual pheromones are released, form one of the distinguishing features of the male-ovipara bixesual pair. They are very abundant in oviparae but completely absent in both males and virginoparae. In a third, rare, category of females which bear a mixed ovary containing both viviparous and oviparous ovarioles, these plaques may still be present but in reduced numbers. A correlation between the number of tibial plaques and that of viviparous and oviparous ovarioles in the ovaries has been found, suggesting that the morphogenesis of this character may be under ovarian control.