河川沙塘鳢的ISSR分析

ISSR Analysis of Odontobutis potamophila

[目的]分析江苏常熟河川沙塘鳢个体大小不一的2个群体之间的遗传差异性。[方法]采用ISSR分子标记技术对2个群体进行遗传分析。[结果]从77个ISSR引物中筛选出3个引物,对2个群体共24个样品进行扩增,获得27个清晰的扩增位点,其中多态性位点19个,多态位点百分率为70.37%。结果表明,大沙塘鳢的遗传多样性水平略高于小沙塘鳢。大小沙塘鳢群体间的遗传距离为0.219 4,群体间的Nei′s遗传分化系数为0.190 4。利用MEGA 3.0软件构建沙塘鳢24个个体的UPGMA系统树,显示出较明显的分支。[结论]江苏常熟河川沙塘鳢种群的遗传多样性水平较低,2个群体的遗传分化已经达到种群分化水平。

[ Objective ] The research aimed to study genetic diversity of Odontobutis potamophila in Changshu of Jiangsu from two populations （ big and small individuals ）. [ Method ] The genetic diversity of two populations was studied using the inter-simple sequence repeat （ISSR） markers. [ Result ] ISSR bands could be differentiated highly in 3 primers after screening. A total of 19 discernible DNA fragments were observed, among which 27 fragments （70.37%） were polymorphic. The percentage of polymorphic （P）, Nei＇s gene diversity and Shannon＇s index showed that the genetic variation of the big population was a little higher than that of the small population. The average genetic distance was 0.219 4 a- mong 24 individuals, and the inter-populations Nei＇s gene diversity coefficient were 0. 190 4. And UPGMA analysis showed that 24 individuals were divided into two clusters corresponding to two populations. [ Conclusion] There was low level of genetic diversity of Odontobutis potamophila population in Changshu of Jiangsu. Two groups of genetic differentiation had reached the level of population differentiation.