银纹夜蛾幼虫气门形态特征的扫描电镜观察

Scanning electron microscopic observation on larval stigma structure of Argyrogramma agnata

采用扫描电子显微镜对银纹夜蛾Argyrogramma agnata Staudinger 5龄幼虫气门的细微结构进行观察。结果表明,银纹夜蛾的幼虫气门的外面观呈二唇状,二唇瓣的内侧向外微凸,唇瓣由若干密生的簇生分枝结构(筛板)组成,在2000倍镜下,筛板呈较规则的刺猬状,在17000倍镜下,簇生分枝圆柱状,柱体光滑,顶端钝圆;筛板的内面观呈平行排列的树形结构,分枝长刺状,单生,分枝数量明显减少。气门外围体壁具有尖塔形纹饰。银纹夜蛾气门的超微结构特征是其长期适应和进化的结果,除具有其本身的生理学意义外,也可作为系统分类的参考依据。

Structure characteristics in larval stigma of Argyrogramma agnata Staudinger was observed with scanning electron microscope （SEM）. The results showed that the stigma filter apparatus of larva of A. agnate was similar to lips in appearance. Inner sides of the lips bulge slightly protruded. Lip petal consisted of many branches crowded closely together. The clustered branches ranked regularly and looked like a hedgehog under 2 000 × SEM. They looked like columns with smooth body and round top under 17 000 × SEM. Filter apparatus showed a parallel treeshape structure, with single and thorn）long branches. The number decreased sharply from an inner view. There were many tower）spire lines on body wall around stigmas. The ultra-structure characteristics of larval stigma in A. agnata resulted from its adaptation to circumstances. It is also very useful to its taxonomy to some extent.