束花石斛种质资源的ISSR分析

Studies on germplasm resources of Dendrobium chrysanthum using ISSR marker

关键词:  束花石斛  种质资源  ISSR  遗传多样性  亲缘关系

Key words:  Dendrobium chrysanthum  germplasms resources  ISSR  genetic diversity  phylogenetic relationship

摘要:

采用ISSR分子标记技术对9个居群束花石斛的遗传多样性和亲缘关系进行分析。结果显示,从60条ISSR引物中共筛选出的5条有效引物,每个引物的扩增位点为9～13个,共56个位点,多态性位点49个(87.90%)。束花石斛种内遗传多态性水平较高,遗传变异较丰富,9个居群的总扩增条带为242个,平均每个居群为26.90个,其中多态性条带占179个(72.90%)。野生束花石斛种质资源减少的主要原因在于人为过度采收和其赖以生长的环境被破坏,聚类分析结果表明,云南思茅和文山居群的遗传距离最近,而云南景洪居群与其它居群之间的遗传距离相对较大,说明束花石斛种内亲缘关系的远近可能与其地理分布也有一定的联系。

Abstract:

Dendrobium chrysanthum is a traditional Chinese crude drug in China. We analyzed the genetic diversity and the genetic relationship of 9 population of D.chrysanthum by ISSR technique in this paper. The results showed that we sieved 5 utility primers from 60 ISSR primers and the amplified loci of every primers was 9～13,the total was 56,of which 49 were polymorphic(87.90% of all amplified loci). The level of genetic diversity in D.chrysanthum is higher,and the genetic variation is more abundance. A total of 242 bands with an average of 26.90 bands per population were amplified from 9 populations,in which 179 bands polymorphic(72.90%)of all amplified bands. The main endangered reasons of wild population of D.chrysanthum were the over-collecting and the environment which D.chrysanthum depended on was destoryed. Cluster analysis showed that the genetic distances of Yunnan Simao population and Wenshan population is closest,and it is farther between Yunnan Jinghong population and the others. This result indicated that the phylogenetic relationship of different population of D.chrysanthum is possibly relevant to their geographic distribution.