青阳参及其近缘种的RAPD研究

RAPD Analysis on Cynanchum Otophyllum and Its Closely Related Species

关键词:  青阳参  隔山消  昆明杯冠藤  RAPD  遗传多样性

Key words:  Cynanchum. Otophyllum Schneid  C．Wilfordii (Maxim.)Hemsl.  C. wallichii Wight  RAPD  genetic diversity

摘要:

目的 针对青阳参Cynanchum otophyllum Schneid.存在混淆种类和种内变异较大的情况，对青阳参和与其相混淆的隔山消C．Wilfordii (Maxim.) Hemsl.和昆明杯冠藤C. wallichii Wight进行种间鉴别，并对青阳参的4个居群进行遗传多样性分析。方法 运用随机扩增多态性DNA(RAPD)技术进行分析，用Shannon指数和Nei指数评价青阳参的遗传多样性，用UPGMA类平均法进行聚类分析亲缘关系。结果 利用筛选出的10个随机引物对供试材料DNA进行随机扩增，共得到72条带，其中多态性带有70条，多态性百分率为97.22%。由Shannon指数计算青阳参4个居群内的遗传多样性比率为68.52％，高于居群间的31.48%；同时由Nei指数估计青阳参4个居群中有69.44％的遗传变异来自居群内，高于居群间的30.56％。采用UPGMA聚类法得出反映各种间亲缘关系的树状图。结论 运用RAPD方法可以进行青阳参和隔山消两个种同昆明杯冠藤的种间鉴别；虽然居群间已有较高分化，但青阳参遗传变异主要分布在居群内。

Abstract:

OBJECTIVE There are confused species on Cynanchum otophyllum Schneid. And distinct intraspecies variation，interspecific indentification has been done among C. otophyllum，C．Wilfordii (Maxim.) Hemsl. And C. wallichii Wight；Genetic diversity of 4 populations of C. otophyllum have been analyzed. METHODS Random amplified polymorphic DNA(RAPD) technique has been used to analyze. Genetic diversity of C. otophyllum has been evaluated by using Nei's gene diversity and Shannon's information index. The dendrogram has been constructed by UPGMA. RESULTS Ten RAPD primers have been selected to apply for random amplification. A total of 72 DNA bands are amplified among which 70(97.22%) are polymorphic. Shannon's information index is 68.52% within the populations of C. otophyllum, more than 31.48% among 4 populations of C.otophyllum; the index Gst is 30.56% among 4 populations of C. otophyllum, less than 68.44% within the populations of C.otophyllum. The dendrogram of genetic relationship among three species has been constructed by using UPGMA. CONCLUSION RAPD is amplified to distinguish C. wallichii form C. otophyllum and C．Wilfordii. Although there is distinct differentiation among populations of C. otophyllum, the great genetic variation happened within populations.