七子花种群遗传多样性的RAPD分析

按胸径将浙江省天台山天然七子花划分为大树、中树、小树和幼树 4个大小级种群 ,利用RAPD分子标记技术对 4个大小级种群共 4 5株个体的遗传多样性及遗传分化进行了比较分析 ,结果表明 :通过 12种随机引物扩增共检测到 6 4个可重复的位点 ,4个大小级种群的多态位点百分率高低为大树 >中树 >小树 >幼树。Shannon信息指数估计七子花 4个大小级种群的遗传多样性高低为大树 >中树 >小树 >幼树 ,大小级种群内的遗传变异占总变异的 5 4 4 1% ,大小级种群间的遗传变异占总变异的 4 5 5 9% ,表明不同大小级种群内、大小级种群间个体均存在一定的遗传分化 ,但大小级种群内的遗传分化比大小级种群间高。Nei指数估计的七子花不同大小级种群的基因多样性的高低与Shannon指数估计的一致 ,大小级种群内的遗传分化高于大小级种群间 ,大小级种群间的基因分化系数为 0 3939。不同大小级种群间的遗传相似度以大树与中树最高 ,大树与幼树最低。聚类分析显示大树与中树先聚成一组 ,小树与幼树再聚成一组 ,最后 2组聚在一起

RAPD Analysis on Genetic Diversity of Populations of Heptacodium miconioides

Heptacodium miconioides collected from Tiantai Mountain of Zhejiang Province was divided into 4 populations according to the size class, namely big tree population, middle tree population, arboret population and young tree population. The genetic diversity within populations and genetic differentiation among 4 populations with different size class (45 samples) were analyzed and compared using random amplified polymorphic DNA (RAPD) technique. The results showed that 64 repeated loci were detected by using 12 random primers. The highest percentage of polymorphic loci was detected in big tree population. The middle tree population took second place and the arboret population took the third place. The lowest percentage of polymorphic loci was detected in young tree population. The highest genetic diversity estimated by Shannon index was revealed in big tree population. The secondary was middle tree population and the third was arboret population. The lowest genetic diversity was revealed in young tree population. 45.59% of genetic diversity was attributed to the differentiation among populations while 54.41% resided within populations. It suggested that the genetic differentiation might exist within and among populations with different size class, but the genetic differentiation within populations was higher than that among populations. The gene diversity estimated by Nei's index was consistent with that estimated by Shannon index and the genetic differentiation within populations was higher than that among populations. The gene differentiation coefficient among populations was 0.393 9. The genetic similarity between big tree population and middle tree population was the highest while that between big tree population and young tree population was the lowest. The clustering analysis was performed using the software POPGENE32 and the results showed that 4 populations with different size class could be divided into 2 clusters, namely cluster 1(big tree population and middle tree population) and cluster 2 (arboret population and young tree population). Furthermore, the two clusters gathered.