瓢虫和草蛉对小麦挥发物组分的行为及电生理反应

Behavioral and electrophysiological responses of four predatory insect species to semiochemicals of wheat

利用触角电位 (electroantennogram, EAG) 和嗅觉测定技术, 比较分析了 4 种捕食性天敌昆虫七星瓢虫 Coccinellaseptempunctata、龟纹瓢虫 Propylaea japonica、中华通草蛉 Chrysoperla sinica和大草蛉Chrysopa septempunctata对麦蚜取食诱导小麦挥发物的行为和电生理反应, 揭示了瓢虫及草蛉类天敌昆虫的嗅觉反应特点。4种捕食性天敌昆虫对麦蚜取食诱导挥发物都有较高的EAG反应值, 七星瓢虫和龟纹瓢虫对6_甲基_5_庚烯_2_酮、6_甲基_5_庚烯_2_醇的反应值较大; 中华通草蛉和大草蛉对6_甲基_5_庚烯_2_醇和水杨酸甲酯的反应值较大, 七星瓢虫对6_甲基_5_庚烯_2_醇的反应值最大, 为0 96±0 18 mV; 4种天敌昆虫对苯甲醛的EAG反应值较低, 对反_2_己烯醛无反应。“Y”型管嗅觉测定结果表明, 4种天敌昆虫对2_莰烯、6_甲基_5_庚烯_2_酮、6_甲基_5_庚烯_2_醇和水杨酸甲酯具有正趋性。说明4种多食性的捕食性天敌昆虫对麦蚜取食诱导挥发物各组分的嗅觉与行为反应各具特点; 寄主麦蚜生境中的嗅觉线索在这4种捕食性天敌昆虫的寄主定位和生境选择中起重要作用。

The electrophysiological and olfactory responses of the four polyphagous predatory insect species, i.e., Coccinella septempunctata, Propylaea japonica, Chrysoperla sinica and Chrysopa septempunctata, to semiochemicals of wheat fed by wheat aphids were studied. Electrophysiological responses of all four species to 6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol, 2-camphene and methyl salicylate were stronger than that of the control. Response of Coccinella septempunctata to 6-methyl-5-hepten-2-ol was the strongest (0.96±0.18 mV). But these natural enemies had no response to E-2-hexenal. \!Y'tube olfactory test showed that 6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol, 2-camphene and methyl salicylate were attractive to them. It was concluded that chemical cues induced by wheat aphid feeding play an important role in host and host habitat location of the four polyphagous predatory natural enemies.