[关键词]
[摘要]
目的 研究我国不同地区天门冬核DNA ITS序列差异及其与地理位置的关系,为不同居群天门冬的鉴定和道地产区的确定提供理论依据。方法 运用PCR法对25个地区的75个样本ITS序列扩增后双向测序,用软件DNAMAN和MEGA 4分析测序结果。结果 每个地区的3个样本的ITS序列基本相同,不同地区样本间的ITS全序列存在一定差异,ITS2片段变异高于ITS1。贵州产天门冬遗传分化度较大,变异位点和信息位点较多。ITS序列构建的系统树表明,同一个地区的3个样本优先聚类,然后是同省的样本聚类,位于北纬24.6°~36.6°和22.2°~24.4°的样本分别聚为1大支;第1大支中包括青海、湖南和贵州省的样本,第2大支则包括浙江、广东、云南和广西4省的样本。结论 ITS序列可鉴定不同产地的天门冬,贵州省是天门冬药材道地产区之一,不同地区天门冬的亲缘聚类主要与纬度相关,与经度关系不大。
[Key word]
[Abstract]
Objective The nuclear DNA ITS sequence variation and its correlation to geographical distribution of Asparagus cochinchinensis from different populations in China were studied, the aims were to reveal the difference among different populations and determine the genuineness of A. cochinchinensis. Methods The ITS fragments of 75 samples from 25 populations were amplified and bidirectional sequenced. And they were analyzed using the software of DNAMAN and MEGA 4. Results ITS sequences of three samples from the same areas were almost the same and ITS sequence of 25 populations were different from each other. The variation of ITS2 sequences was bigger than that of ITS1sequences. ITS sequences of Guizhou Province had bigger genetic differentiation and more variable sites and information sites than other provinces had. Clustering results based ITS sequences showed three samples from the same area firstly clustered and then populations from a province clustered. All populations were divided into two branches based on North latitude of 24.6°—36.6°and 22.2°—24.4°, the first branch included the populations of Qinghai, Hunan, and Guizhou Provinces, the second branch included the populations of Zhejiang, Guangdong, Yunnan and Guangxi Province. Conclusion ITS sequences could identify the different populations of A. cochinchinensis. Guizhou Province is the place of genuineness of A. cochinchinensis. Clustering the different populations of A. cochinchinensis primarily relates to the latitude while has little relationship with the longitude.
[中图分类号]
[基金项目]
湖南省高校创新平台开放基金项目(09K106);湖南省科技计划重点项目(2009FJ2008)