【摘要】 运用随机扩增多态DNA(RAPD)技术,对峨眉含笑(Michelia wilsonii)自然分布区的5个自然种群的遗传多样性进行了研究。从100个随机引物中筛选出能产生清晰、稳定的多态性标记引物18个,共检测出107个位点,其中多态性位点为93个,占86.92%,在物种水平上,等位基因的有效数目、Nei’s的基因多样性系数(He)和Shannon表型多样性指数(I)分别为1.740 4、0.4175和0.597 4;总的遗传变异量(Ht)为0.339 3,其中居群内遗传变异量(Hs)为0.259 1,各居群间的遗传分化系数(Gst)达到0.321 9。应用UPGMA法对遗传距离进行聚类分析构建树系图,结果表明,峨眉含笑自然种群具有较高的遗传多样性;其种群间的遗传差异与其地理分布有关。更多还原

【Abstract】 The genetic variations within and between five natural populations of Michelia wilsonii from different distribution regions were investigated at the DNA level by employing RAPD.Out of 100 random primers,eighteen random primers were screened which could generate highly reproducible and clear RAPD fragments for further population analysis.With these primers,a total of 107 discernible DNA fragments were obtained and 93(86.92%) were polymorphic.At species level,the effective number of allele(He) was 1.7404.Nei’s gene diversity was 0.417 5 and Shannon index was 0.5974.Total genetic diversity(Ht) was 0.339 3,and the genetic diversity within populations(Hs) was 0.259 1.The coefficient of gene differentiation(Gst) among populations was 0.321 9.UPGMA map were made according to the genetic similarity and distance of the five populations calculated.The results showed that M.wilsonii had a high genetic diversity.The genetic diversity of M.wilsonii among the five natural populations was primarily related to its geographic distribution.更多还原