长江下游地区4个克氏原螯虾群体的遗传多样性分析

Genetic diversity in four Procambarus clarkii populations in the lower reaches of the Yangtze River

为了对长江下游地区克氏原螯虾(Procambarus clarkii)群体的遗传多样性状况进行本底调查,本文利用17对微卫星引物对南京(NJ)、盱眙(XY)、合肥(HF)、南昌(NC)4个克氏原螯虾地理群体进行了遗传多样性研究。结果表明,4个地理群体的平均观测杂合度为0.4322–0.4826、平均期望杂合度为0.4024–0.6121、平均多态信息含量为0.3408–0.5624,4个克氏原螯虾群体的遗传多样性处于中等水平,其中南京群体遗传多样性最高,合肥群体最低;4个克氏原螯虾群体的基因流为1.3729–5.9161,遗传分化指数为0.0405–0.1540,群体间基因流水平较高,群体间遗传分化程度较小。聚类结果显示4个群体可分为2支:南京、南昌、盱眙三个群体聚为一支,合肥群体独自成一支。以上结果将为克氏原螯虾遗传育种、资源保护和利用提供一定的理论依据。

To estimate genetic variation and provide genetic information for resource protection and breeding efforts, individuals of the invasive red swamp crayfish （Procambarus clarkii） from four populations along the lower reaches of the Yangtze River （Nanjing, Xuyi, Hefei and Nanchang） were characterized using 17 microsatellite loci. In these populations, the mean observed heterozygosity （Ha）, mean expected heterozygosity （He）, and mean polymorphism information content （PIC） ranged from 0.4322 to 0.4826, from 0.4024 to 0.6121, and from 0.3408 to 0.5624, respectively, indicating a medium level of genetic diversity. The highest and lowest genetic diversity were found in the Nanjing population and Hefei population, respectively. Gene flow （Nm） ranged from 1.3729 to 5.9161, and population differentiation （Fst） ranged from 0.0405 to 0.1540. Cluster analysis using the UPGMA method showed that the Nanjing and Nanchang populations clustered first, and then clustered with the Xuyi population, and finally all groups together clustered with the Hefei population.