Abstract
In the yellow peach moth, a synthetic sex pheromone consisting of (E)-10-hexadecenal and (Z)-10-hexadecenal showed significantly lower attraction than crude pheromone extracts in wind tunnel tests. Synergistic effects of a non-polar fraction (NPF) from the crude pheromone extract on the activity of a polar fraction (PF), including aldehydes, were assessed in wind tunnel tests. NPF itself showed no activity, but the number of males attracted close to the source was significantly increased when it was added to PF. Similar synergistic effects were also observed in a female body wax (FBW) extract and its NPF but not in male body waxes. Effects of NPF from both sources dose-dependently increased and the active dose range of NPF in FBW was larger than that of the crude pheromone extract. New unknown components that synergistically improve the activity of aldehyde components may be non-polar compounds in FBW. The actual sex pheromone system of the yellow peach moth may consist of aldehydes (attractive over a long distance) and non-polar components in female body wax that functions as a cue for the final recognition of females.
