Response of the Woodborers Monochamus carolinensis and Monochamus titillator (Coleoptera: Cerambycidae) to Known Cerambycid Pheromones in the Presence and Absence of the Host Plant Volatile α-Pinene

In recent years, several attractant pheromones have been identified for cerambycid beetles, including 2-(undecyloxy)-ethanol (hereafter monochamol) for Monochamus galloprovincialis (Olivier), M. alternatus Hope, and M. scutellatus (Say). This study screened eight known cerambycid pheromones or their analogues (including monochamol) as potential attractants for M. carolinensis Olivier and M. titillator (F.), in the presence and absence of the host volatile alpha-pinene. Monochamol attracted M. carolinensis in the presence and absence of alpha-pinene, whereas M. titillator was only attracted to the combination of monochamol and alpha-pinene. (2R*, 3R*)-2,3-Hexanediol also attracted both M. carolinensis and M. titillator, but only in the presence of alpha-pinene. Subsequent coupled gas chromatography-mass spectrometry and gas chromatography-electroantennogram detection analyses of extracts of volatiles collected from both sexes demonstrated that male M. carolinensis and M. titillator release monochamol, and that antennae of males and females of both species detect it. These results indicate that monochamol is a male-produced pheromone for both M. carolinensis and M. titillator.