中文摘要：

为了研究棉铃虫Helicoverpa armigem（Htibner）和烟青虫Hassulta（Guenée）2种近缘种昆虫寄主差异和寄主转移的味觉机制，本研究利用单感受器记录和叶碟法测定了棉铃虫和烟青虫5龄幼虫下颚栓锥感器对烟碱、辣椒素、棉酚和番茄苷等植物次生物质的电生理反应和取食选择行为。结果表明，棉铃虫幼虫中栓锥感器内存在对番茄苷和棉酚敏感的味觉神经元，而烟青虫侧栓锥感器和中栓锥感器内分别存在对辣椒素和烟碱敏感的味觉神经元。棉酚能够显著诱导棉铃虫5龄幼虫的取食选择行为，但是供试次生物质并不能显著影响烟青虫幼虫的取食选择行为。

英文摘要：

The gustatory mechanism of host-difference and host-shift between two closed lepidopteran species, Helicoverpa armigera （Htibner） and H. assulta （Guenée） were investigated by measuring the electrophysiology responses of sensilla styloconica and feeding preference behaviors of the 5^th instar lar- vae to nicotine, capsaieine, gossypol and tomatine using the tip recording and the leaf-dlsc choices bi- oassay. The results show the medial sensillum of H. armigera responded to tomatine and gossypol strongly, suggesting active tomatine and gossypol neurons in medial sensillum. For H. assulta larvae, the lateral sensillum responded to capsaicine and medial sensillum responded to nicotine, suggesting an active eapsaicine neuron in lateral sensillum and a nicotine neuron in medial sensillum of H. assulta. The gossypol could significantly induce the feeding preference of H. armigera larvae, while the tested secondary plant substances had no significant effects on the feeding preference behaviors of H. assulta.