福建省桫椤科植物的分子分类学研究

桫椤科科下等级设立长期以来存在一定的争议，以福建省内5种桫椤科植物刺桫椤（Alsophila spinulosa(Hook,)Tryon）、黑桫椤（Gymnosphaera podophylla(Hook.)Copel.）、针毛桫椤（G.metteniana (Hance)Tagawa）、粗桫椤（G.hancokii (Copel,)Ching）、牛姆林桫椤（G.niumulinensis Li,Chen et Deng）（新拟）为材料，采用改进的CTAB法获得了纯度较高，得率高，片段完整（片段大小均大于23kb）的基因组DNA，并运用RAPD技术对这5种桫椤进行了遗传多样性分析，从40个10－mer随机引物中筛选30个有效引物，产利用这30个有效引物共扩增出1073条DNA带，利用UPGA法以桫椤科的5个种的种间亲缘关系进行聚类分析，得出5个种的DNA分子分类系统图。结果表明，可以分为毛桫椤、棘桫椤和黑桫椤3组，平均遗传距离为0．61，符合属间的关系，从而确定了RAPD技术用于桫椤植物分子分类研究的可行性。结合前人在形态解剖学方面的工作，提出这5种桫椤科植物可以分为3个类群，即刺桫椤类、黑桫椤类和针毛桫椤类，并提供了3个类群的检索表。

Study on Molecular Taxonomy of 5 Species of Cyatheaceae in Fujian

The classification of the species of Cyatheaceae has been disputative for a long time. Genetic method of RAPD was used to analyse the genetic distance of 5 species of Cyatheaceae in Fujian Province. Their DNAs were extracted by the CTAB method. 30 effective primers were screened from 40 arbitrary primers, and 1 073 DNA bands were amplified. Based on UPGA cluster analysis on DNA bands amplified by 30 primers, a DNA molecular dendrogram was established. The 5 species of Cyatheaceae can be divided into 3 groups. Group A, B, C consist of Gymnosphaera metteniana and G. hancockii, Alsophila spinulosa , and G. podophylla and G. niumulinensis , respectively. The 3 groups of Cyatheaceas plants have been posed from the 5 species combining our molecular analysis with reported morphological and anatomical results.