Geographic and gender differences in semiochemicals in emerging adult southern pine beetle (Coleoptera: Scolytidae)

Six semiochemicals, important in the communication system of southern pine beetle, Dendroctonus frontalis Zimmermann, were isolated from hindguts of individual beetles from Texas, South Carolina, and North Carolina. Females had mole cis-verbenol (cV) and trans-verbenol (tV) than males, but males contained much more verbenone (V). Both sexes had the same amounts of frontalin (F), endo-brevicomin (eB), and alpha-pinene (alpha P). Geographic differences were found in quantities of tV and V in both sexes, and in alpha P and F in males only. Males produced predominantly (+)-cV and (+)-V and (-)-F, (-)-eB, and (-)-V. The (+) enantiomer of alpha P predominated in both sexes, but the percentage of (+)-alpha P was generally lower than that released from beetle-infested logs from the same areas. Geographic differences in enantiomeric composition of tV and V were significant in males, and of eB in females. Behavioral implications of the results are discussed.