Sex pheromone of Callosobruchus subinnotatus

Article abstract of DOI:10.1023/A:1020899407497

Sex pheromone produced by Callosobruchus subinnotatus females stimulates conspecific males to walk upwind toward the source. Gas chromatographic and mass spectrometric analyses of sex pheromone components and their hydrogenated derivatives suggested that the sex pheromone consisted of two short-chain fatty acids, (E)-3-methyl-2-heptenoic acid (E32C7) and (Z)-3- methyl-2-heptenoic acid (Z32C7). The composition of the sex pheromone was confirmed by electrophysiological and behavioral bioassays with synthetic compounds. A mixture of 5 ng E32C7 and 5 ng Z32C7 elicited a 2.1-mV male EAG response, whereas the solvent control elicited 0.1 mV. Mixtures of the two compounds at various ratios were attractive to males in Y-tube bioassays. A pitfall-type trap equipped with a lure impregnated with 1 ng E32C7 and 1 ng Z32C7 was effective in trapping males. Traps baited with the lure caught 80% of males in a glass aquarium during nighttime and 50% during daytime, whereas control traps (solvent treated) in a separate aquarium caught 20% and 10%, respectively.