Abstract
In this study, we examined an aggressive behavior of soldiers of Japanese subterranean termite (Reticulitermes speratus) against pseudergates of the same colony, when the soldiers were exposed to the essential oils from coniferous trees. We tested six essential oils from conifers, and found the essential oils from Chamaecyparis obtusa bogwood, Cryptomeria japonica heartwood and C. japonica leaf and Pinus thunbergii leaf to cause the aggressive behaviors for soldier termites. From the C. obtusa bogwood essential oil, we obtained active fractions by the thin layer chromatography, and recognized calamenene as the main compound to cause the aggressive behaviors. Sixteen monoterpenes as contained in some coniferous leaf were also examined in the activities of promoting the aggressive behaviors, and terpinen-4-ol showed the frequency of the behavior among the compounds.
