Partial inhibition of pheromone production inDendroctonus ponderosae (Coleoptera: Scolytidae) by polysubstrate monooxygenase inhibitors.

Female and male mountain pine beetles,Dendroctonus ponderosae Hopkins, were treated topically with piperonyl butoxide or sesame oil, both of which are known to inhibit poly substrate monooxygenase activity. Beetles then exposed to vapors of the host monoterpenes α-pinene and myrcene were found to contain reduced levels of the pheromonestrans-verbenol and ipsdienol, as well as a buildup of monoterpene precursors. Polysubstrate monooxygenase enzymes appear to be at least partially responsible for the detoxification of host monoterpenes and for the production of terpene alcohol pheromones in this species.