利用ISSR标记对7个硬叶兜兰居群160个体扩增，10对引物共扩增出101个条带，其中多态性条带97个，种水平上的多态性条带比率（PPB）达96．02％，香侬指数（I）为0．4889，Nei's基因多样性指数（H）为0．3324。居群水平的遗传参数，多态性条带比率（PPB）为33．51％，香侬指数（I）为0．1943，Nei's基因多样性指数（H）为0．1332。总的遗传多样性（HT ）为0．3239，个体遗传多样性（Hs ）达到0．1332。AMOVA结果揭示居群间遗传分化大，居群间基因流 Nm 为0．3492。居群间的Nei's遗传距离0．1481～0．4385。基于UPGMA聚类，在遗传距离为0．327时，7个居群聚为两支，第一支由古林箐和马固、田坝、夹寒箐和杨柳井居群组成，第二支由斗咀和小坝子居群组成，聚类关系反映居群间遗传分化与地理距离无显著相关性。%Paphiopedilum micranthum has the high ornamental value known as slipper orchids ,which was restrictedly distributed in karst limestone areas of southeast Yunnan ,southwest Guizhou ,northern and western Guanxi Province .This study focused on the genetic diversity of 7 populations from Southeast Yunnan detected by ISSR markers .101 bands were generated from 160 individuals by 10 primers ,among which 97 bands belonged to polymorphic and each primer amplified 10 .1 bands .There was a higher genetic diversity index at species level (PPB=96 .02% ;I=0 .488 9 ;H=0 .332 4) ,but a lower genetic diversity index at population level (PPB= 33 .51% ;I= 0 .194 3 ;H = 0 .133 2) .Total gene diversity reached 0 .323 9 and gene diversity within populations attained to 0 .133 2 .Nei's genetic differetation among popu-lations (Gst )was 0 .148 1-0 .438 5 .Gene flow (Nm ) was 0 .349 2 .These indicated that there was a higher population differentiation among populations .Based on the UPGMA cluster dendrogram ,the seven popu-lations were classfied into two groups at genetic distance of 0 .327 .First group included Gulinqing ,Magu , Tianba ,Jiahanqing and Yangliujing ;Second group was made up by Douzui and Xiaobazi populations .The cluster result indicated that there was no significant correlation between genetic distance and geographical distance .
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