不同水系银鲴自然群体线粒体COI基因遗传变异研究  

Genetic variation of Xenocypris argentea between different populations based on mitochondrial COI gene

作　　者：刘军[1] 赵良杰[1] 刘其根[1] 张宏[1] 

机构地区：[1]上海海洋大学农业部淡水水产种质资源重点实验室,上海201306

出　　处：《淡水渔业》2015年第6期3-8,21,共7页Freshwater Fisheries

基　　金：公益性行业(农业)专项"湖泊水库养殖容量及生态增养殖技术研究与示范"(201303056);国家自然科学基金(31072218);上海市高校知识服务平台项目(ZF1206)

摘　　要：为了解银鲴（Xenocyprisargentea）的遗传资源状况，利用线粒体COl基因序列比较分析长江、钱塘江和黑龙江水系中银鲴群体的遗传多样性和种群分化情况。结果显示，在110条528bp的COl序列中，碱基T、C、A、G的平均含量分布为27．13％、18．56％、28．70％、25．61％，检测出变异位点15个。多样性分析显示，各地理种群单倍型多样性均较高，核苷酸多样性均较低，长江群体单倍型多样性（0．742±0．053～0．911±0．033）高于黑龙江（0．731±0．087）和钱塘江（0．552±0．137）群体，推测与不同地理群体所处生境多样性有关。单倍型网络结构显示出明显的地理分布格局，3个群体两两之问都存在显著的遗传分化，分子变异方差分析（AMOVA）也显示银鲴群体的遗传变异主要发生在水系之问（40．21％），进一步说明银鲴种群之问的遗传分化与种群问的地理隔离有关。种群历史分析显示，只有长江群体的中性检测呈现显著的负值（FS=-7．07821，P〈0．05）且岐点分布呈现明显的单峰，共同支持该群体在近期发生过种群扩张事件，而钱塘江和黑龙江两群体与长江群体都经历着不同的种群历史事件。In order to understand the genetic resources of Xenocypris argentea,genetic diversity and population differentiation of X. argentea in Yangtze River,Qiantangjiang River and Heilongjiang River were analyzed using mitochondrial COI gene. In the 528 bp sequences, the average nucleotide percentage composition of T, C, A, G of X. argentea were27. 13%,18. 56%,28. 70%,25. 61%,15 variable sites were detected. Genetic diversity showed that all the 3 populations were characterized with high haplotype diversity and low nucleotide diversity. The Haplotype diversity of Yangtze River( 0. 742 ± 0. 053 ~ 0. 911 ± 0. 033) was higher than Heilongjiang River( 0. 731 ± 0. 087) and Qiantangjiang River( 0. 522 ± 0. 137),Haplotype network showed clear geographic distribution pattern. There were significant genetic differences among the three geographic populations. Analysis of molecular variance( AMOVA) of the 3 populations showed that the genetic variance mainly presented among groups( 40. 21%),we considered geographical isolation was related to genetic differentiation of X. argentea populations. The neutrality tests of Yangtze River population appeared significant negative( FS =- 7. 078 21,P < 0. 05),and the mismatch distribution analysis presented obvious single peak,which suggested that Yangtze River population had experienced population expansion. The demographic history of Yangtze River was different from Qiantangjiang population and Heilongjiang population.

关 键 词：银鲴(Xenocypris argentea) COI 遗传多样性 种群分化 

分 类 号：S917.4[农业科学—水产科学]