我国不同地区天门冬核DNAITS序列分析

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.