Rafaeli, A., Inst. Technol. Storage Agric. Prod., ARO, Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel
Bober, R., Inst. Technol. Storage Agric. Prod., ARO, Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel, Department of Entomology, Hebrew University, P.O. Box 12, Rehovot 76100, Israel

In a previous study we showed that juvenile hormone (JH) or its analog, fenoxycarb (FX), is involved in the up-regulation of pheromone biosynthesis-activating neuropeptide (PBAN) competence. JH causes induction of binding to a putative PBAN-receptor (PBAN-R) and the subsequent pheromone production by pheromone glands of pharate females. The present study demonstrates that pheromone production by the adult female is age-dependent. The pheromonotropic response increased to reach a maximum at 4 days, after which a decreased response was observed. Binding of the PBAN-R was also age-dependent. Treatment with FX inhibited both binding of PBAN to the PBAN-R and the pheromonotropic response as reflected by the production of the main pheromone component, Z-11-hexadecenal. Thus, in contrast to its up-regulatory role in pharate females, FX treatment of adult females causes down-regulation of both pheromone production and specific binding to the PBAN-R. In addition, behavioural observations showed that calling behaviour, mating success and subsequent egg-fertility are affected by treating females with FX. © 2005 Elsevier Ltd. All rights reserved.