Abstract: Random amplified polymorphic DNA (RAPD) technique was applied to assess six Fagus species in China. Fifty-six of eighty tested arbitrary primers generated obvious bands with size ranging from 250 to 3050bp. An index of genetic similarity(F)was calculated and the value of (1-F) was used to evaluate genetic distances between species to construct dendrogram. The result suggested that three species，F.pashanica, F.hayaatae and F.hayatae var.zhejiangensis, had closer relationship and should be clustered into a single species. This was in good agreement with our morphological work. Based on RAPD markers,we suggested that Chinese beech species should be divided into four species, F.longipetiolata, F.engleriana, F.lucida and F.hayaatae (including F. pashanica and F.hayatae var.zhejiangensis).

Key words: Fagus, RAPD technique, genetic distance

摘要： 应用随机引物扩增多态性DNA(RAPD)方法，对我国水青冈属(Fagus L.)6种植物，即巴山水青冈(F.pashanicaF.longi petiolata)、米心水青冈(F.engleriana)、亮叶水青冈(F.lucida)、台湾水青冈(F.hayatae)和浙江水青冈(F.hayatae var.zhejiangensis)进行基因组多态性分析，选用80个随机引物进行扩增，其中56个引物扩增出清晰可重复的条带，片段大小在250～3050bp之间。 采用UPGMA法对求出的遗传片段进行聚类分析。结果显示：台湾水青冈、巴山水青冈和浙江水青冈的遗传距离较近，表明它们可归并为一种。这与我国水青冈属的生态解剖学研究结果完全一致。根据结果将我国水青冈植物归并分为4种：长柄水青冈、米心水青冈、亮叶水青冈、台湾水青冈(包括巴山水青冈和浙江水青冈)。

关键词: 水青冈, RAPD技术, 遗传距离