内蒙古高原小叶锦鸡儿与中间锦鸡儿遗传多样性的研究

Genetic Diversity of Caragana microphylla and Caragana intermediain Inner Mongolia Plateau

利用ISSR分子标记,选取内蒙古高原自东向西共15个锦鸡儿种群(7个小叶锦鸡儿种群,8个中间锦鸡儿种群)进行遗传多样性分析。结果表明:(1)7个小叶锦鸡儿种群总的多态位点百分数为98.19%,Nei’s基因多样性指数与Shannon信息指数分别为0.289 7、0.444 0;居群间遗传分化系数Gst为0.119 0,表明小叶锦鸡儿种群存在中等程度的遗传分化;居群间基因交流频繁,基因流(Nm)为3.701 0。(2)8个中间锦鸡儿种群多态位点百分数为99.7%,Nei’s基因多样性指数为0.312 8,Shannon信息指数为0.478 4;居群间遗传分化系数(Gst)为0.188 1,表明中间锦鸡儿种群存在较大的遗传分化,基因流(Nm)为2.157 8。(3)中间锦鸡儿遗传多样性及遗传分化均高于小叶锦鸡儿,这是中间锦鸡儿替代小叶锦鸡儿适应不良环境扩展分布的遗传基础。(4)邻接聚类分析结果显示,15个锦鸡儿种群表现为从东到西逐渐聚类,体现了这2个种在分布上的地理渐变性及地理替代性;遗传多样性各指数与气象因子及土壤因子之间的相关性分析表明,平均气温对锦鸡儿种群的遗传分化起着重要的作用。

The genetic diversity of 15 Caragana populations （7 Caragana microphylla populations and 8 Caragana intermedia populations） from east to west at Inner Mongolia Plateau was analyzed by ISSR （in- ter-simple sequence repeats） markers. The results showed that the percentage of polymorphic loci of 7 C. microphylla populations was 98.19% ;Nei＇s gene index and Shannon information index were 0. 289 7 and 0. 444 0, respectively~ the genetic differentiation coef{icient（Gst） was 0. 119 0,which showed that there is a moderate genetic differentiation in C. microphylla populations; and the gone flow （gin） among populations was frequently（3. 701 0）. （2）The percentage of polymorphie loci of 8 populations of C. intermedia was 99.7 %, Nei＇ s gone index was 0.312 8, Shannon information index was 0. 478 4 ; the genetic differentiation coefficient（Gst） was 0. 188 1, which showed that C. intermedia population have great genetic differentiation; the gene flow （Nm） was 2. 157 8. （3） Genetic diversity and genetic differentiation of C. intermedia both higher than that of C. microphylla, which is genetics base that C. intermedia instead of C. microphyl- la to adapt to adverse environmental and extended distribution. （4）Neighbor cluster analysis showed that 15 Caragana populations is gradually from east to west,which reflected both in the gradual change of ge- ography distribution and geographic alternative. Correlation analysis of genetic diversity index and meteoro- logical factors and soil factors showed that the average temperature plays an important role in Caragana populations genetic differentiation.