白杨派,青杨派和黑杨派的DNA多态性及系统进化研究

收集了杨属三个派内２０个种的２８个无性系，筛选７个引物进行ＲＡＰＤ分析。共产生５４条有效谱带，其中４３条（７９．６３％）表现多态性。任意两无性系间的遗传距离（Ｄ）为０．９３０￣０．０３１，相应其相似性为０．５１８￣０．９７０。以Ｄ值为基础研究三个派的系统进化关系，聚类结果表明三个派明显独立，且青杨派与黑杨派关系较近，而与白杨派则相对较远，结合其它研究成果推测白杨派较早从杨属中分离出来，而青杨派和黑

STUDY ON DNA POLYMORPHISMS AND PHYLOGENETICS OF POPULUS: AIGEIROS, TACAMAHACA AND LEUCE SECTION

Twenty-eight Poplar(Populus) clones belonging to 20 species covering three section were screened for polymorphic RAPD(Randon Amplified Polymorphic DNA) markers with 7 arbitrary primers (5 20-mer and 2 10-mer Oligonucleotide). With these total of 54 different DNA bands were reproducibly obtained, 79. 63% of which were polymorphic. The genetic distance (D) between these clones ranged from 0. 930 to 0. 031, corre- spending to the similarity from 0. 518 to 0. 970. RAPD fingersprints were used to estimate the taxonomic and phylogenetic relationship. The dendrogram showed the species or clones belonging to the same section were clustered into a same group, i. e. there were three groups on behalf of sect. Leuce, Aigeiros and Tacamahaca, respectively. They also showed that the relationship between Aigeiros and Tacamahaca was closer than that between Aigeiros or Tacamahaca and Leuce. It was presumed that sect. Leuce was separated from genus Populus prior to the other two sections.