6种瓢虫的RAPD分析及在分类上应用的研究

利用随机引物分别对6种瓢虫的DNA进行了聚合酶链式反应（RAPD－PCR）的实验。结果显示，用相同引物扩增不同种瓢虫的基因组DNA，扩增产物多态性DNA片段的数目是不同的；两种不同引物的扩增产物中，各自呈现出种、属的特异性片段，其可用于种、属的鉴别；聚类图显示了种、属之间亲缘关系的远近程度，并与形态学分类结果相一致。实验分析还发现：七星瓢虫不同个体间多态性DNA特有带较多，遗传较稳定；龟纹瓢虫与之相比，不同个体间多态性DNA的特有带较少，变异程度较大。

RAPD analysis and its application to taxonomy of six species of lady beetles

Six species of lady beetles were analyzed by Random amplified polymorphic DNA (RAPD). The result showed that the amplified products from the same primer in different species were different .The characteristic bands of each species and genus were found in amplified products from two primers, which are useful for identification of species and genus. The cluster analysis displayed that the relationship of species and genus coincided with morphological taxonomy. It was also found that there were more common bands in amplified products of different individuals in Coccinella septempunctata . So its heredity should be more stable. Compared with Coccinella septempunctata , there were less common bands in Propylaea japonica . So its variation should be more.