School of Forest, Fisheries and Geomatics Sciences, University of Florida, Gainesville, FL, 32611, USA.
Synergy Semiochemicals Corp., 7572 Progress Way, Delta, BC, V4G 1E9, Canada.
J Chem Ecol. 2022 Aug;48(7-8):641-649. doi: 10.1007/s10886-022-01361-7. Epub 2022 May 3.
The black turpentine beetle, Dendroctonus terebrans, is an economically important pest of pines in the Southeastern U.S., with a high potential for invasion to other pine-rich regions. Dendroctonus terebrans attraction to an injured host tree lessens over time as the host material degrades. Likewise, kairomonal volatiles emitted from the host change as constituents of the defensive resin oxidize. Therefore we hypothesized that volatiles associated with a fresh host would be more attractive to D. terebrans than those associated with a dead or dying host. We replicated the natural oxidation process of turpentine, fractionated the distilled products to isolate the oxidized products, and deployed the complex mixtures to measure field attraction based on the amount of oxidation performed. Contrasting with previous studies, our results suggest that D. terebrans attraction is not primarily based on host tree degradation. In a second experiment incorporating Dendroctonus pheromones, we demonstrate D. terebrans has a displacement-dependent response to endo-brevicomin, a pheromone associated with the sympatric southern pine beetle, D. frontalis. This has implications not only for possible interspecific signaling, but also for the role of endo-brevicomin in D. terebrans colonization behavior. The results from this study broaden the understanding of D. terebrans chemical ecology and directly contribute to the development of an effective lure-based monitoring system that will benefit future research and management efforts. This may become important if the species is established outside its native range, as in the closely related red turpentine beetle, Dendroctonus valens, which caused mass pine tree mortality following its introduction to Asia.
黑松甲虫，Dendroctonus terebrans，是美国东南部松树的一种重要经济害虫，具有入侵其他富含松树地区的高潜力。随着宿主材料的降解，Dendroctonus terebrans 对受伤宿主树的吸引力会随着时间的推移而减弱。同样，从宿主中释放的信息素挥发物也会随着防御树脂成分的氧化而发生变化。因此，我们假设与新鲜宿主相关的挥发物对 D. terebrans 的吸引力会大于与死亡或垂死宿主相关的挥发物。我们复制了松节油的自然氧化过程，对蒸馏产物进行了分离以分离出氧化产物，并根据氧化程度部署了复杂的混合物来测量野外吸引力。与以前的研究相反，我们的结果表明，D. terebrans 的吸引力不是主要基于宿主树的降解。在第二个实验中，我们纳入了 Dendroctonus 信息素，证明 D. terebrans 对与其同域的南方松甲虫 D. frontalis 相关的内 - 短叶烯具有依赖位移的反应。这不仅对可能的种间信号传递具有影响，而且对 endo-brevicomin 在 D. terebrans 定殖行为中的作用也具有影响。本研究的结果拓宽了对 D. terebrans 化学生态学的理解，并直接有助于开发有效的基于诱饵的监测系统，这将有益于未来的研究和管理工作。如果该物种在其原生范围之外建立，这可能变得很重要，就像其亲缘关系密切的红松甲虫 Dendroctonus valens 一样，它在引入亚洲后导致大量松树死亡。
