我国华东地区两种茶尺蛾的形态和分子鉴定

External morphology and molecular identification of two tea Geometrid moth from southern China

【目的】我国华东地区两种严重危害茶树的害虫灰茶尺蛾Ectropis grisescens Warren,1894和茶尺蠖Ectropis obliqua(Prout,1915)的形态相似、分类不清,在农业生产中常常混淆,给防治工作的开展带来了相当大的困难。为了准确的鉴别灰茶尺蛾和茶尺蠖,本文对这两种害虫进行了形态学观察和分子特征分析。【方法】对灰茶尺蛾和茶尺蠖成虫、卵、幼虫和蛹的形态特征进行了比较分析;并对灰茶尺蛾和茶尺蠖的39个样本的线粒体COⅠ基因进行了扩增和测序,分析了两物种种内和种间的遗传距离,并基于Kimura-2-parameter模型,利用ML和NJ法构建系统发育树。【结果】灰茶尺蛾和茶尺蠖部分形态学特征具有显著差异;分子数据表明二者种内和种间遗传距离存在明显的"barcoding gap",利用ML和NJ法构建的系统发育树可以将灰茶尺蛾和茶尺蠖成功的区分开。【结论】基于COⅠ基因的分子鉴定结果与形态学鉴定结果相符合,可用于害虫防治和相关研究中。

Ectropis grisescens Warren, 1894 and Ectropis obliqua （Prout,1915）,two serious pests of tea in south-eastern China, are morphologically similar and cannot easily be distinguished, which makes it difficult to conduct research on these pests. To accurately identify E. grisescens and E. obliqua,we examined and compared morphological characters and the mitochondrial CO I gene sequences of these two species. [Methods] Morphological characters of adults, eggs, larvae and pupae of each species were observed, illustrated, measured and compared. 39 samples of the mitochondrial CO I gene of E. grisescens and E. obliqua were amplified and sequenced, and the intraspecific and interspecific divergences of the two species were calculated. NJ and ML trees were built based on the Kimura-2-parameter model. [Results] The results show that there are obvious morphological differences between E. grisescens and E. obliqua and there is an obvious “barcoding gap” in the intraspecific and interspecific divergences of these species that allows them to be distinguished by NJ and ML trees. [Conclusion] The results of morphological identification were consistent with molecular methods based on CO I gene variation. The results should be useful for preventing crop damage by these two pests and related research.