甘肃省3种裂腹鱼遗传多样性与地理种群分化
Genetic diversity and population differentiation of three Schizothoracinae fishes in Gansu Province

于甘肃省境内长江水系、黄河水系和内陆河水系共8个采样点，采集3种裂腹鱼亚科鱼类——黄河裸裂尻鱼(Schizopygopsis pylzovi)、祁连裸鲤(Gymnocypris chilianensis)和嘉陵裸裂尻鱼(Schizopygopsis kialingensis)样本294尾，以线粒体Cyt b基因为分子标记，对3种裂腹鱼的系统发育关系进行分析，并对其不同地理种群的遗传多样性现状与遗传分化情况进行研究。基于NJ和BI法构建的单倍型分子系统发育树结果发现,黄河裸裂尻鱼构成单系,且具有较高支持率；而嘉陵裸裂尻鱼位于祁连裸鲤的分支内部。遗传多样性分析结果显示，70尾黄河裸裂尻鱼的 Cyt b基因共检测出23个单倍型，单倍型多样性及核苷酸多样性分别为0.917和0.003 10；132尾祁连裸鲤的Cyt b基因共检测出28个单倍型，单倍型多样性及核苷酸多样性分别为0.819和0.009 82；92尾嘉陵裸裂尻鱼的 Cyt b基因共检测出13个单倍型，单倍型多样性及核苷酸多样性分别为0.706和0.002 33。种群遗传分化研究结果表明，这3种裂腹鱼同一物种的不同地理种群间均存在显著的遗传分化，该结果揭示了地理隔离对3种裂腹鱼有显著的阻隔影响，对整体的分化适应有重要作用，因此在资源保护管理中应当作为不同的单元分别加以对待。
In the present study,294 Schizothoracinae specimens of Schizopygopsis pylzovi, Gymnocypris chilianensis and Schizopygopsis kialingensis,were collected from 8 sampling sites from the Yangtze River,the Yellow River and inland rivers in Gansu Province.Mitochondrial DNA Cyt b gene was used as molecular marker to perform the phylogenetic analyses,genetic diversity and population differentiation analysis of the 3 Schizothoracinae fishes.Phylogenetic analyses of all haplotypes based on NJ and BI methods revealed that S. pylzovi was clustered as a monophyletic group.However, S. kialingensis was clustered into a clad with G. chilianensis,suggesting that the two species are under early stage of speciation.Genetic diversity analysis showed that a total of 23 haplotypes were detected in the Cyt b gene of 70 S. pylzovi,with the haplotype diversity and nucleotide diversity being 0.917 and 0.003 10,respectively.A total of 28 haplotypes were detected in the Cyt b gene of 132 G. chilianensis,with the haplotype diversity and nucleotide diversity being 0.819 and 0.009 82,respectively.A total of 13 haplotypes were detected in the Cyt b gene of 92 S. kialingensis,with the haplotype diversity and nucleotide diversity being 0.706 and 0.002 33,respectively.No haplotypes were shared between either two different species,and significant population differentiation were detected among geographic populations,showing that geographic isolation has a significant impact on these Schizothoracinae fishes,and adaptive differentiation as well.Hence,different populations should be treated as different evolutionary significant units in conservation management