西南大西洋阿根廷滑柔鱼遗传多样性的微卫星分析

西南大西洋阿根廷滑柔鱼(Illex argentinus)是重要的经济大洋性头足类,其种群结构较为复杂。本研究采用8个微卫星标记,对西南大西洋阿根廷滑柔鱼群体的遗传多样性进行了检测。8个基因座位上,共检测出172个等位基因,每个基因座位检测到10～30个等位基因不等。8个位点的平均观测等位基因数为21.500 0,平均有效等位基因数为12.074 1。各位点的观测杂合度(Ho)变化范围为0.300 0～0.775 0,期望杂合度(He)为0.484 2～0.977 0,平均观测杂合度为0.504 6,平均期望杂合度为0.873 4。8个微卫星位点的多态信息含量(PIC)平均值为0.853 6。以卡方检验估计Hardy-Weinberg平衡,发现8个基因座位均不符合Hardy-Weinberg平衡。Fst分析显示该群体无明显的遗传分化。研究结果揭示:西南大西洋阿根廷滑柔鱼种群显示了高水平的微卫星多态性,该海域阿根廷滑柔鱼群体的遗传多态性水平在经历了近十年的密集捕捞压力后没有明显的变化,同时证明微卫星分子标记是研究该物种自然种群的有利工具。

Analysis of genetic diversity of Illex argentinus population in southwest Atlantic using microsatellite markers

Illex argentinus is an important economic oceanic fishery species with complex population structure in southwest Atlantic ocean.In this paper,genetic diversity of Illex argentinus population in southwest Atlantic was analyzed using 8 microsatellite markers.172 alleles varying from 10 to 30 alleles per locus were acquired from 8 microsatellite markers.The mean observed number of alleles was 21.500 0,the mean effective number of alleles was 12.074 1 and the mean polymorphisms information content value was 0.853 6.In all samples,the observed heterozygosity was from 0.300 0 to 0.775 0 and the expected heterozygosity was from 0.484 2 to 0.977 0.The Hardy-Weinberg equilibrium was checked by X2 test,suggesting that all locus deviated from Hardy-Weinberg equilibrium.Fst analysis suggested that no genetic differentiation was detected in this population.In conclusion,the population of Illex argentinus showed a high levels of microsatellite diversity,and that level of genetic variability has not changed during almost a decade of intensive fishing pressure,suggesting that these markers will be the useful tool for studies on natural populations of the genus.