红脂大小蠹后肠挥发性物质的鉴定、触角电位和室内趋向实验

Identification and electroantennal olfactory and behavioral tests of hindgut-produced volatiles of the red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Scolytidae)

对外来松树害虫红脂大小蠹DendroctonusvalensLeConte的信息化学物质进行了研究。通过GC_MS测定 ,鉴定出红脂大小蠹后肠挥发性物质中 ,除了含有松树挥发性物质α_蒎烯、β_蒎烯、3_蒈烯、月桂烯和柠檬烯外 ,还含有马鞭草烯醇和马鞭草烯酮 ;利用触角电位技术 ,对马鞭草烯醇、马鞭草烯酮以及在林间引诱效果最好的 3_( + )_蒈烯进行了触角电生理测试 ;利用Y_型双向选择嗅觉仪对这些物质进行了室内趋向实验。实验结果表明 :1 μg的马鞭草烯醇、马鞭草烯酮和 3_( + )_蒈烯引起雌雄触角的电位反应分别达 4 1 6 μV 470 μV、5 97μV 6 3 0 μV和 92 6 μV 1 0 99μV。浓度为 1 μL mL的马鞭草烯酮引起红脂大小蠹的正趋向反应 ,而在 1 0 0 μL mL浓度下引起红脂大小蠹的负趋向反应 ;在 1 μL mL的浓度下 ,3_( + )_蒈烯引起了红脂大小蠹正趋向反应 ,而马鞭草烯醇则对红脂大小蠹具有驱避作用 ,说明这些物质在红脂大小蠹搜寻寄主和调节虫口密度方面起着重要作用。

An exotic invasive pine pest, red turpentine beetle, Dendroctonus valens LeConte (Scolytidae), was studied. GC-MS analysis confirmed the existence of verbenol and verbenone as well as the host volatiles (α-pinene, β-pinene, 3-carene, myrcene and limonene) in hindguts of the beetle. Verbenol, verbenone and 3-(+)-carene, the most effective attractant in field test, all elicited electroantennal responses in EAG (electroantennogram) test. Indoor olfactory tests with a Y-type tube were conducted. Verbenone was attractive to D. valens at 1 μL/mL, and its effect could parallel that of 3-carene; however, 100 μL/mL of verbenone was somehow repellent to the beetle. Verbenol was repellent to D. valens in all dosages.