棉铃虫为害诱导棉花内物质含量变化

由于昆虫为害的影响,植物往往能产生有利于自身而不利于害虫的变化,从而避免或减轻虫害。如在甘薯组织中,正常情况下几乎不存在多酚化合物,在受到虫害后12h就开始合成[1],大白菜被盲蝽Lygusclisponsi取食后,在取食点周围组织内酚类化合物含量增加,并且过氧化物酶活性也增强[2]。我们在室内对棉花受二代棉铃虫Helicoverpaarmigera（Huhuer）的为害进行模拟实验,研究了棉花受害后叶内次生物质和营养物质的含量变化。1材料与方法棉花品种（系）：表现为高抗的有590s;中抗的有HG－BR－8、291、中12;感虫的有Pay－784、中无383－12…     

棉铃虫和烟青虫幼虫下颚栓锥感器对某些化合物反应特性的比较

利用电生理学技术,以两个食性有差异的近缘种棉铃虫和烟青虫为研究对象,比较研究了6龄幼虫下颚上两对栓锥感器对刺激取食素和抑食素的感受机理.结果表明:(ⅰ)两种幼虫栓锥感器对蔗糖和印楝素敏感的细胞均主要分布在侧栓锥感器,对肌醇敏感的细胞主要分布于中栓锥感器;(ⅱ)烟青虫幼虫中栓锥感器对肌醇刺激的反应敏感性强于棉铃虫;(ⅲ)在测试的6种抑食素中,仅印楝素在两种昆虫的侧栓锥感器上可诱导高的神经脉冲;(ⅳ)抑食素对刺激取食素引发栓锥感器神经脉冲有抑制作用,其中对于棉铃虫,辣椒素对蔗糖引发脉冲的抑制率最大,番茄苷对肌醇引发脉冲的抑制率最大,棉酚对蔗糖和肌醇引发脉冲的抑制率均为最小;对于烟青虫,单宁、棉酚和番茄苷对蔗糖引发脉冲均有较大的抑制率,棉酚对肌醇引发脉冲的抑制率最大,烟碱对蔗糖和肌醇引发脉冲的抑制率均为最小.     

Comparative study on the responses of maxillary sensilla styloconica of cotton bollwormHelicoverpa armigera and Oriental tobacco budwormH. assulta larvae to phytochemicals

Using the electro-physiological technique, the sensory mechanisms of maxillary sensilla styloconica to stimulants and deterrents were explored on two closely related species, the generalist Helicoverpa armigera and the specialist H. assulta. The results showed that: (i) in both species, cells sensitive to sucrose and azadirachtin were mainly in the lateral sensillum styloconicum, and those to inositol were in the medial sensillum styloconicum; (ii) sensitivity of medial sensillum styloconicum in H. assulta to inositol was higher than that in H. armigera; (iii) among 6 tested deterrents, only azadirachtin evoked high impulse discharge from the lateral sensillum styloconicum in both insects; (iv) the deterrents could disturb stimulants evoking impulse discharge from maxillary sensilla styloconica of both species in different degrees: To sucrose evoking impulses on lateral sensillum styloconicum, for H. armigera capsaicin had a strong inhibition and gossypol had a weak inhibition, while for H. assulta tann