Hydrocarbon Components in Contact Sex Pheromone of the White-Spotted Longicorn Beetle, Anoplophora malasiaca (Thomson)(Coleoptera : Cerambycidae) and Pheromonal Activity of Synthetic Hydrocarbons

GC-MS analyses revealed more than 40 hydrocarbons in the hexane fraction from silica gel column chromatography of female elytra extract, which evoked mating behavior in male Anoplophora malasiaca when blended with the ether fraction. When the hexane fraction was separated into saturated, monoenyl, dienyl and trienyl fractions by column chromatography on silica gel impregnated with silver nitrate, only the fraction that contained saturated hydrocarbon showed pheromonal activity when mixed with the ether fraction. This activity was comparable with that observed when the mixture of the eight major synthetic hydrocarbons was blended. The eight major hydrocarbons were n-heptacosane, n-nonacosane, 4-methylhexacosane, 4-methyloctacosane, 9-methylheptacosane, 9-methylnonacosane, 15-methylhentriacontane and 15-methyltritriacontane. These hydrocarbons were indicated to be the components of the contact sex pheromone in A. malasiaca, which works together with an unknown polar component(s).