Genetic diversity of four diploid loach（Misgurnus anguillicaudatus ） populations in the middle and lower Yangtze River Basin | 长江中下游二倍体泥鳅4个种群的遗传多样性

chinois. 利用12对微卫星引物对长江中下游4个二倍体泥鳅野生种群的遗传多样性进行了分析。结果表明：12个微卫星位点在武汉、洞庭湖、鄱阳湖和太湖4个种群中总共检测到64个等位基因，每个位点的等位基因数为2～11，平均等位基因数为5．3。每个种群的平均等位基因丰度（An）为3．502～4．615，平均观测杂合度（Ho）为0．395-0．517，平均期望杂合度（HE）为0．360-0．515，平均多态信息含量（PIC）为0．332-0．465，说明4个种群表现出中度的遗传多样性。在12个位点中有4个偏离Hardy-Weinberg平衡（HWE），每个种群均不同程度偏离HWE，表现为杂合子不足。种群问遗传分化系数（Gsr）为0．118，15．74％遗传变异源于种群间差异，表明种群间存在中度遗传分化。种群间遗传距离（D）为0．067-0．206，太湖与鄱阳湖种群间遗传距离最大。聚类分析表明，洞庭湖与鄱阳湖种群聚为一支、亲缘关系较近，武汉种群与太湖种群聚为另一支。[著者文摘]

anglais. Twelve microsatellite markers from loach were used to investigate genetic diversity of four natural populations for diploid loach Misgurnus anguillicaudatus in the middle and lower Yangtze River Basin. In the four populations from Wuhan（WH）, Dongtinghu Lake （DT）, Poyanghu Lake（PY） and Taihu Lake（TH）, 64 alleles were detected in 12 loci. The number of alleles per locus was from 2 to ll,and the average number of alleles per locus was 5.3. In each population, the average allelic richness （AR） was from 3. 502 to 4. 615,the average observed heterozygosity（Ho） was from 0. 395 to 0. 517, the average expected heterozygosity（HE） was from 0. 360 to 0. 515, and the average polymorphic information content（PIC） was from 0. 332 to 0. 465. These genetic statistics indicated a moderate genetic diversity in the four populations. Significant deviations from Hardy-Weinberg equilibrium（HWE） occurred at four out of 12 loci. Deviations from HWE were also found in each population and all of them showed heterozygosity deficit. The coefficient of gene differentiation between populations（GsT） was 0. 118, and 15.74% of total genetic variation was resulted from differences among populations, which indicated moderate val- ues of genetic differentiation between populations. Genetic distance（D） among populations ranged from 0. 067 to 0. 206, and the maximum occurred between TH and PY populations. The cluster analysis showed that DT and PY populations were clustered into one branch and their relationship was nearer, WH and TH populations were clustered into another branch. The present results on the genetic diversity of diploid loach populations provide important information for natural resources conservation and genetic breeding of M. anguillicaudatus.