中药盘龙参ITS的序列分子鉴定研究

Identification of Spiranthes sinensis (Pers) Ames by rDNA ITS Sequences

为研究盘龙参DNA分子鉴定方法,采用改良CTAB法提取盘龙参总DNA,根据rDNA ITS基因片段(AB 740176)设计引物,对样本进行PCR扩增,扩增产物克隆并测序,MEGA 5.2软件分析。结果表明:扩增得到的rDNA ITS片段总长为667 bp,ITS变异位点比率为17.10%,信息化位点比率为6.56%;通过ITS序列构建系统树进行聚类分析表明,ITS序列在绶草属种内是保守的,可作为中药盘龙参分子鉴定标记,而绶草属的系统发生关系尚需进一步研究。

To identify Spiranthes sinensis （Pers） Ames by ITS. The total DNA of the sample was extracted by modified CTAB, designed a pair of primers based on rDNA ITS sequence（ AB 740176）, amplified cloned and sequenced, analyzed by MEGA 5.2. The Results showed that ： The length of rDNA ITS fragment from sample was 667 bp,ratio of the variable sites was 17.10% and the singleton site 6.56%. The genetic distance and the phylogenetic tree based on ITS data were set up. The ITS gene fragments were highly conservative at intraspecific level in Spiranthes, Hence, the sequence of this fragment was a good molecular marker for authentication of the S. sinensis （Pers）. But further study was necessary for the phylogenetic of Spiranthes.