铁皮石斛及其混伪品的rDNA ITS序列分析与鉴别

目的]从分子水平上实现对铁皮石斛及其混淆品快速准确的鉴别。方法]通过对铁皮石斛及其混淆品的rDNA ITS区序列进行分析,计算遗传距离,并采用邻接法构建NJ系统树。结果]8个来自不同产区的铁皮石斛rDNA ITS区序列全长636 bp;铁皮石斛及其6个常见混淆品药材ITS序列长度范围为636～641 bp,其中ITS区(不包括5.8S)片段长度为483 bp,含信息位点60个(12.4%),变异位点185个(38.3%);各样品间遗传距离范围为1.108%～2.594%,NJ系统树也表明铁皮石斛与其混淆品的亲缘关系较远。结论]ITS序列可对铁皮石斛及其混淆品进行快速简便的鉴别。

The Genuine and Adulterants Identification of Dendrobium officinale by rDNA ITS Sequences Analysis

Objective] To accurately identify D.officinale and its adulterants on the molecular level.Method] Through the analysis of rDNA ITS sequences of D.officinale and its adulterants,the genetic distance was calculated,and a NJ systematic tree was established by the neighbor-joining method.Result] The results showed that the full length of rDNA ITS regions of 8 D.officinale samples from different producing areas was 650 bp,the length of ITS sequences(not including 5.8 s) of D.officinale and its 6 adulterants varied from 598 bp to 601 bp.Of 483 total sites in ITS1and ITS2,60 were informative sites(12.4%),185 were mutable sites(12.4%).The distance between D.officinale and its adulterants was 1.108% to 2.594%.The NJ trees also indicates the relationship and differences of D.officinale and its adulterants.Conclusion] It was concluded that ITS sequence can be used to discriminate between D.officinale and its adulterants rapidly and accurately.