云锦杜鹃自然居群遗传多样性的ISSR分析

 利用ISSR技术对浙江省境内的5个云锦杜鹃自然居群的遗传多样性进行分析。12个引物共检测到170个位点, 其中多态位点150个, 多态位点百分率P (% ) 为88.24%。物种水平的Shannon信息指数( I) 为0.4317, Nei指数( h) 为0.2848, 表明物种水平的遗传多样性很高; 而居群水平的遗传多样性较低, P%平均为48123%, I平均为0.2682, h平均为0.1818。AMOVA分子差异分析显示40.03%的变异存在于居群间, 59.97%的变异存在于居群内, 居群间的遗传分化明显。居群间的基因流较低, 为0.8824。居群隔离、自交衰退可能是导致云锦杜鹃居群间遗传分化的主要原因。5个居群间的平均遗传距离为0.1755。聚类显示, 括苍山居群和天台山居群组成一组, 凤阳山居群和百山祖居群组成另一组, 干坑居群单独成一组。

Genetic Diversity in the Natural Populations of Rhododendron fortunei Revealed by ISSR Molecular Markers

Genetic diversity in the five natural populations of Rhododendron fortunei in Zhejiang province of China were analyzed using inter simple sequence repeat(ISSR)molecular markers.A total of 170 loci,150 of which were polymorphic ones,were detected in natural populations of Rhododendron fortunei using 12 ISSR primers.Total percentage of polymorphic loci(P,%)was 88.24% in the species,while Shannon's information index(I)and Nei's gene diversity(h)were 0.4317 and 0.2848,respectively.These indicated that the genetic diversity of Rhododendron fortunei was relatively high.In the contrary,the genetic diversity at population level of Rhododendron fortunei was relatively low.The mean value of P%,I and h were 48.23%,0.2682 and 0.1818,respectively.Analysis of molecular variance(AMOVA)demonstrated that the among-population component accounted for 40.03% of the total variations,while the within-population component accounts for 59.97%.The genetic differentiation was relatively high and the gene flow was low(0.8824).These results suggested that population isolation and inbreeding regression may play the main roles in the genetic differentiation among Rhododendron fortunei populations.The pair-wise mean genetic distance among populations was 0.1755.The clustering analysis showed that KCS population and TTS population were in one group,FYS population and BSZ population in another group,and GK population separated from all the other populations in the dendrogram.