山杨杂种无性系的SSR分子标记遗传多样性

采用5对SSR引物对52个山杨杂种无性系进行了遗传多样性检测，结果表明在研究的5个位点上SSR标记多态位点百分率为100%，平均等位基因数为4.4个，有效等位基因数最多的位点是PTR7，最少的位点为PTR12；欧美山杨杂种的遗传多样性最丰富，相比之下，中美山杨杂种遗传变异最低；聚类分析表明，在一定的遗传距离基础上，欧美山杨杂种和欧洲山杨首先聚为一类，然后又与中美山杨杂种聚类，最后是中国山杨。研究表明来自芬欧美山杨杂种具有较高的遗传多样性，这对我国山杨遗传资源的扩大，以及未来山杨杂交育种，杂种优势的利用都是重要的。

Genetic diversity among the clones of aspen hybrid detected by simple sequence repeat DNA marker

Using 5 pairs of SSR primers, the genetic diversity of 52 hybrid clones of Aspen is detected. The result shows that percentage of polymorphic loci is 100% in five loci studied, in which the average number of alleles is 4.4, the locus PTR7 is the greatest amount in effective alleles, and the locus PTR12 is the least. Besides, there is the highest genetic diversity among the clones of Populus tremula×P.tremuloides, and the lowest variation in that of P.davidiana×P.tremuloides; By cluster analysis on the basis of genetic distance, it demonstrates that hybrid of P.tremula×P.tremuloides and P.tremula are firstly clustered, and then hybrid of P.davidiana×P.tremuloides, P.davidiana are finally clustered. This study demonstrates that hybrid clones of Populus tremula×P.tremuloides from Fenland have higher genetic diversity than the other Aspen clones, what is very important to enlarge genetic sources, cross breeding and heterosis utilization of this species in the future.