Effects of Ratio and Amount of the Two Sex-Pheromonal Components of the Diamondback Moth on Male Behavioral Response

Abstract

The responsiveness of male diamondback moth to its sex pheromone was examined in the laboratory. The responses were observed in a flask after chemicals adsorbed on a piece of filter paper were provided. Male response showed a peak at a dose of 1×10^-3 μg on the filter paper with 1 : 1 mixture of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecenal. Response decreased when the chemicals were increased to more than 1×10^-3 μg and finally was completely inhibited by 1μg of chemicals; the optimum concentration inducing male sexual behavior was determined. Optimum ratio of the mixture ranged from 8 : 2 to 5 : 5 (acetate : aldehyde) when the amount was fixed at 1×10^-3 μg and no sharp perk was observed.