棉铃虫5龄幼虫对棉酚和印楝素的味觉适应性行为研究

【目的】研究棉铃虫幼虫对棉酚和印楝素的味觉适应性行为，为棉铃虫的防治提供参考依据。【方法】采用叶碟法和味觉感受器切除法进行不同取食条件下棉铃虫5龄幼虫的取食选择行为试验。供试化合物为处理后终浓度为2mmol／L的棉酚和印楝素。【结果】正常人工饲料饲养的棉铃虫幼虫对棉酚和印楝素均十分敏感，取食对照叶碟量显著高于处理叶碟（P〈0．05）；切除中栓锥感受器后棉铃虫幼虫取食含棉酚或含印楝素的叶蝶量与正常叶碟有显著差异（P〈0．05），而切除侧栓锥感受器后棉铃虫幼虫取食含棉酚或含印楝素的叶蝶量与正常叶碟差异不显著（P〉0．05）；以含有低浓度取食抑制素的人工饲料饲养的棉铃虫幼虫对棉酚和印楝素不敏感，取食对照叶碟量与处理叶碟无显著差异（P〉0．05）。【结论】棉酚和印楝素是棉铃虫幼虫的取食抑制素，侧栓锥感受器中含有对棉酚和印楝素敏感的味觉神经元，不同取食经历的棉铃虫幼虫对棉酚和印楝素具有行为适应性。

Taste adaptability to azadirachtin and gossypol in fifth instar larvae of Helicoverpa armigera

Objective]The aim of this research was to provide references for pest control by studying the taste adaptability to gossypol and azadirachtin in Helicoverpa armigera. Method]The leaf dish method and taste sensilla ablation were used to investigate the taste plasticity on the deterrents in 5^th instar larvae of H. armigera which were reared on different artificial diets at 2 mmol/L gossypol and azadirachtin. Result]The larvae reared on normal artificial diets were sensitive to gossypol and azadirachtin.The consumption of control leaf discs was significantly higher than that of the treatedones （P〈 0.05）. For the larvae without medial sensillum styloeonica, the consumption of leaf discs with gossypol or azadirachtin was significantly different from that of the control （P〈0.05）. However, for the caterpillars without lateral sensillum styloconica , the consumption of leaf discs with gossypol or azadiraehtin was not significantly different from that of the control （P〉0.05）. Meanwhile, the caterpillars reared on the artificial diets containing low deterrents showed insensitivity to the deterrents （P〉0.05）. Conclusion ] Gossypol and azadiraehtin are deterrents for H. armigera. The lateral sensillum styloconiea con- tains the taste neurons sensitive to deterrents and there is taste adaptability in caterpillars with different feeding experience.