中日5个岛屿山茶种群遗传多样性研究

Study on population genetic diversity of Camellia japonica in 5 islands between China and Japan

关键词:  山茶  ISSR  岛屿  遗传多样性  遗传结构

Key words:  Camellia japonica  ISSR  island  genetic diversity  genetic structure

摘要:

运用ISSR分子标记法对中、日两国5个岛屿天然山茶种群共150个个体进行遗传多样性分析。结果表明：筛选出的20条引物扩增得到205条清晰条带，其中183条为多态性条带，多态位点百分比（PPB）为89.27%。经POPGENE软件分析，山茶种群平均多态位点百分比（PPB）为72.00%，Nei’s基因多样性指数（HE）为02743，Shannon信息多态性指数（H）为0.4023，种群水平遗传多样性较高。基因分化系数Gst=02033，表明遗传变异主要存在于种群内个体间。Mantel检验（r=0.7989，P＜0.05）和UPGMA聚〖JP〗类表明岛屿地理隔离对山茶种群遗传分化具有重要影响。基于岛屿山茶种群遗传结构的分析，建议加强我国岛屿自然种群的就地保护力度。

Abstract:

Camellia japonica is an important horticultural species，widely distributed in East Asia. 5 populations of C.japonica collected from China and Japan were analyzed by ISSR markers to detect the genetic diversity. A total of 205 discernible loci were obtained from all populations using 20 primers. Of these loci，89.27% were polymorphic(PPB=89.27%). The average percentage of polymorphic loci(PPB=72.00%)，Nei’s gene diversity(HE=02743)and Shannon’s Information Index(H=0.4023)，estimated by POPGENE，indicated that C.japonica had higher level genetic diversity than many other insular plant species. The coefficient gene differentiation(Gst)was 02033，which showed more variation were from the individuals of the populations. According to Mantel Test（r=07989，P＜0.05）and UPGMA，insular geographical isolation have an important influence on genetic structure. In order to maintain genetic diversity and resource utilization of C.japonica that natural population should be protected in situ from human disturbance to facilitate its natural generation.