Perception of Conspecific Female Pheromone Stimula

Authors: Hangkyo Lim Kye Chung Park Thomas C Baker Michael D Greenfield

Publish Date: 2007/04/14

Volume: 33, Issue: 6, Pages: 1257-

PDF Link

Abstract

Perception of the female sex pheromone in Utetheisa ornatrix Lepidoptera Arctiidae is responsible for induction and adjustment of calling by females and the collective phenomenon termed “female pheromonal chorusing” We found five olfactoryactive compounds in the U ornatrix female gland When females were exposed to the entire pheromone or to two of its synthetically prepared components ZZZ369eicosatriene and ZZZ369heneicosatriene they were more likely to call during a given night begin calling earlier and briefly increase signal frequency with which they extrude their abdomen an observable indication of calling in this species Some females even initiated calling during photophase when exposed to the pheromone components In general female U ornatrix are more sensitive to the complete blend of pheromone than to its individual compounds We also tested the hypotheses 1 that abdominal extrusion per se increases the rate of pheromone release and 2 that greater abdominal pumping rhythm increases pheromone release rate Contrary to our expectations 1 females did not respond more strongly to a pulsed pheromone stimulus than to the constant release of pheromone at the same average release rate and 2 we did not find a relationship between the frequency of abdominal pumping and pheromone release rate Possible explanations for these unexpected findings are discussedWe thank M Deyrup of the Archbold Biological Station Highlands County Florida for helping us collect U ornatrix and its host plants We also thank M Y Choi W E Conner T Eisner V Iyengar and C W LaMunyon for providing critical information on U ornatrix biology and pheromone analyses during various stages of the project and R Jurenka for providing us with synthetic pheromone components J Kelly and two anonymous reviewers offered valuable critiques of earlier versions of the manuscript K M Nus and J A Campbell of the Division of Biological Sciences at the University of Kansas took care of the host plants and provided test facilities A M Swatek served as an invaluable laboratory assistant The Hungerford Fund and the Entomology Graduate Student Summer Scholarship at the University of Kansas Department of Ecology Evolutionary Biology provided financial support

Keywords: