Submitted to: Agricultural Economics Review
Publication Type: Research Notes
Publication Acceptance Date: May 17, 2002
Publication Date: N/A
Technical Abstract: Regulation of pheromone release is critical for intraspecific communication and avoidance of predators release is critical for intraspecific communication and avoidance of predators or parasites dependent on such messages. Pheromone production is under endocrine control in insects (1,2). However, mechanisms controlling the amount of pheromone released are poorly understood. I report a potential feedback system in Colorado potato beetle (CPB) that may enable CPB to measure and regulate pheromone release. Male CPB release quantities of an aggregation pheromone, (S)-CPB I, undetectable by gas chromatography (3). Release of (S)-CPB I is enhanced by excision of one or both antennae and topical application of juvenile hormone III (JH III). Excision of both antennae and JH III treatment result in synergistic amounts of pheromone that are sustained for day. These results with CPB confirm our earlier study with boll weevil in which the feedback system was first discovered (4). In other Coleoptera, JH III may stimulate corpora cardiaca to release a brain hormone (BH) that induces pheromone biosynthesis (5). Since JHA increased pheromone levels and decreased sensitivity of olfactory receptors in boll weevil, JH may regulate pheromone release by modulating olfactory sensitivity. Thus, a negative feedback loop may exist comprised of neural and hormonal signals; it includes pheromonal stimulation of antennal receptors that leads to decreased pheromone release. (1) Vanderwell D. 1994 Arch Insect Biochem. Physiol 25:347. (2) Tillman, J. A. et al. 1999. Insect Biochem Molec Biol 29:481. (3) Dickens, J.C. et al. 2002 J. Exp. Biol. In press. (4) Dickens, J.C. et al 1988. J. Entomol Sci. 23:52. (5) Hughes, P. R. and Renwick, J. A.A. 1977. Physiol Entomol. 2:117.