Electroantennographic Responses of Wild and Laboratory-Reared Females of Eichhoff and (Fabricius) (Coleoptera: Curculionidae: Scolytinae) to Ethanol and Bark Volatiles of Three Host-Plant Species

Chemical ecology studies on ambrosia beetles are typically conducted with either wild or laboratory-reared specimens. Unlike laboratory-reared insects, important aspects that potentially influence behavioral responses, such as age, physiological state, and prior experience are unknown in wild specimens. In this study, we compared the electroantennographic (EAG) responses of laboratory-reared and wild and to 70% ethanol and bark odors (host kairomones) of , , and aged for 2, 24, and 48 h. Chemical analyses of each odor treatment (bark species x length of aging) were performed to determine their volatilome composition. EAG responses were different between laboratory-reared and wild when exposed to ethanol, whereas wild exhibited similar EAG responses to the laboratory-reared insects. Ethanol elicited the strongest olfactory responses in both species. Among the bark-odors, the highest responses were triggered by at 48 h in , and at 24 and 48 h in . Volatile profiles varied among aged bark samples; 3-carene and limonene were predominant in , whereas α-copaene and α-cubebene were abundant in Further studies are needed to determine the biological function of and terpenes on and and their potential application for the development of effective lures.