同域分布两种鲤科鱼类种群遗传结构的比较

Comparison of population genetic structure of two co-distributed cyprinid species

为了解河南省境内黄河水系和卫河水系棒花鱼和条的鱼类遗传多样性现状,利用线粒体细胞色素b(cytb)基因,对这两种鱼类开展群体遗传学研究。结果显示,棒花鱼和条群体多态性较低;系统发育树和单倍型网络图结果显示棒花鱼和条均由3个线粒体谱系组成;棒花鱼和条种群间均存在明显的遗传分化,种群间中等偏低的基因流解释了两种鱼类均具有较低的遗传多样性和明显的种群分化;群体历史动态分析显示,棒花鱼和条种群数量分别在距今约0.019百万年和0.026百万年开始锐减。鉴于群体多态性,种群分化和群体历史动态研究,这两种鱼类的遗传多样性均较低,需加强对其资源保护。

In order to estimate and compare the genetic diversity and population structure between Abbottina rivularis and Hemiculter leucisculus in the Yellow River and Weihe River in Henan province, we used cytb sequences to estimate population genetic parameters and tested for demographic fluctuations. Our results showed that the population polymorphism of the two species was low. The results from phylogenetic tree, as well as haplotype network structure, showed that A. rivularis and H. leucisculus had three distinct lineages, however, there was no phylogeographic structure. The gene flow with moderate to low among populations explained that the two species had lower genetic diversity and distinct population differentiation. Then we analyzed the Demographic History of A. rivularis and H. leucisculus. Bayesian skyline plot revealed that the stock of the two species declined dramatically 0.019 and 0.026 million years ago, respectively. In view of the population polymorphism, population differentiation and demographic history, we concluded that the genetic diversity of A. rivularis and H. leucisculus was low in this study, and it was necessary to strengthen the protection of their resources.