Sex pheromone of Ascogaster quadridentata, a parasitoid of Cydia pomonella

Porapak Q volatile extracts of female Ascogaster quadridentata, an egg-larval endoparasitoid of codling moth, Cydia pomonella, bioassayed in Y-tube olfactometers attracted male, but not female, A. quadridentata. Coupled gas chromatographic-electroantennographic detection (GC-EAD)analysis of bioactive extracts revealed three compounds that elicited responses by male A. quadridentata antennae. CC-mass spectra (MS) indicated, and comparative analyses of authentic standards confirmed, that these compounds were (Z,Z)-9,12-octadecadienal, (Z)-9-hexadecenal, and 3,7,11-trimethyl-6E,10-dodecadienal. (Z,Z)-9,12-Octadecadienal alone attracted laboratory-reared male A. quadridentata in Y-tube olfactometer and field-cage bioassays, and attracted feral A. quadridentata in a field experiment. This sex pheromone could be used to help detect populations of A. quadridentata, delineate their distributions, and determine potential sources of parasitoids for capture and release in integrated programs for control of C pomonella.