淮河克氏原螯虾种群遗传结构

Population Genetic Structure of Red Swamp Crayfish in Haihe River Wetlands

克氏原螯虾(Procambarus clarkii)是广泛分布于我国淡水水域的外来入侵物种,对其种群遗传结构的研究有助于了解种群扩散过程。本文测定了淮河流域自然水体中9个地理种群共151个野生克氏原螯虾线粒体COⅠ序列,获得624 bp的有效基因片段,共定义了25个单倍型。AMOVA分析结果表明,淮河流域的克氏原螯虾种群内的变异占主导地位,单倍型多样性和核苷酸多样性均为中等水平,各地理种群间平均遗传差异较小(F st=0.078),遗传差异不显著。系统发生树并没有按地理位置形成对应族群,表明克氏原螯虾各地理种群间存在明显的基因流,各地理种群间没有形成明显的种群遗传分化。

Procambarus clarkii is an alien invasive crayfish species which is widely distributed in wetlands in China. Clarification of P. clarkii population genetic structure will help to understand its spread process. Here, we analyzed the population genetic structures of 9 populations of 151 crayfish individuals in Huaihe river based on the CO I region. The results showed that the 624 bp long CO I region aligned across 25 haplotypes. AMOVA showed that intra-population variation （92. 20% ） was much higher than inter-population variation （7.80%）. Haplotype diversity and nucleotide diversity were moderate, and the differentiation among populations was non-significant （F, = 0. 078）. Phylogenetic tree shows that the genealogical clusters do not match the sample locations well, suggesting that genetic differentiation among them is not remarkable, while the gene flow is evident.