长江中上游圆口铜鱼群体遗传结构研究

为科学地开展圆口铜鱼人工繁殖和增殖放流等保护工作，研究采用9个四碱基重复的圆口铜鱼（Coreius guichenoti）微卫星标记，对采自宜昌、三峡库区、宜宾、永善、巧家、攀枝花6个江段的199尾圆口铜鱼样本的遗传多样性和遗传结构进行了分析。依照采样点不同将圆口铜鱼分成6个群体，研究结果显示，9个微卫星标记均具有较高的多态性，各群体遗传多样性水平较高。AMOVA显示6个群体并未达到显著遗传分化水平。Structure分析将6个群体分为2组，三峡库区群体中部分个体与宜宾群体中部分个体为一组，其他为另一组。分子方差分析（AMOVA）结果与Structure分析结果间存在一定差异，可能原因在于AMOVA结果是将每个群体作为一个整体来显示的，而Structure分析结果是将每个群体按照个体数所占比例来显示的。因此，为避免遗传背景污染事件的发生，进行圆口铜鱼人工繁殖的遗传管理，分析比较放流群体和野生群体的遗传结构是必须的

Population Genetic Structure of Coreius guichenoti in the Upstream and Middle Reaches of the Yangtze River

In order to scientifically carry out the artificial breeding and release protection work of Coreius guichenoti, 199 samples of six populations of C. guichenoti were collected from the upstream and middle reaches of the Yangtze River (Yichang, Three Gorges Reservoir area, Yibin, Yongshan, Qiaojia, and Panzhihua). A total nine polymorphic tetranucleotide microsatellites of the six populations were analyzed in this study. The results demonstrated that all the nine microsatellite loci were highly polymorphic, and the six populations had high genetic diversities. AMOVA analysis revealed there were no significant differences in the six populations. Nevertheless, Structure analysis showed that the six populations could be divided into two groups. One group included some individuals from the Three Gorges Reservoir population and some from the Yibin population, while the other samples were involved in another group. The results difference between AMOVA and structure analysis might be due to that, all samples in each population were identified as a single factor in AMOVA, but structure analysis recognized the samples proportion in each population. Therefore, in order to avoid the occurrence of genetic background pollution events, it is necessary to do the genetic management of artificial breeding of C. guichenoti and analyze their genetic structure of the released stock and nature population