本文对药材藁本及其常见混伪品的rDNA ITS2进行了PCR扩增、测序,并运用MEGA软件对该区进行序列分析,比较了ITS2碱基序列的差异及其规律,同时为药材藁本及混伪品的指纹图谱鉴别提供分子标记。结果显示辽藁本的种内差异较小,而与其主要混伪品间存在较大的变异,差异性范围为5.7%~35.3%。根据ITS2序列特征构建的系统树,药材藁本的样品紧密的聚在一起,和其混伪品可以明确区分,支持率为100%。此外,ITS2的二级结构可作为鉴定药材藁本及混伪品种的一个方法,具有一定的系统学及分类学意义。本研究表明rDNA ITS2序列分析可作为药材藁本与混伪品的一种有效的分子鉴定方法,具有重要的应用价值。

This study aimed to compare the rDNA ITS2 differentiation and its regulation between Ligustici rhizoma et radix and its adulterants in order to provide DNA molecular markers for the fingerprint identification between them.In this study,the rDNA ITS2 regions of Ligustici Rhizoma et Radix and its adulterants were amplified and sequenced,and then analyzed by using MEGA software.The results showed that ITS2 sequences of Ligustici Rhizoma et Radix have proper intra-/inter-specific divergence,the range of diversity among Ligustici Rhizoma et Radix and its adulterants was 5.7%-35.3% based on ITS2.Phylogenetic tree based on ITS2 sequence data indicated samples of Ligustici Rhizoma et Radix clustered to form a independent branch,which was supported by high bootstrap value(100%).Therefore,the rDNA ITS2 sequence is a powerful molecular marker for the identification of Ligustici Rhizoma et Radix and its adulterants.

卫生部卫生行业科研专项(200802043):药用植物DNA barcoding(条形码)鉴定研究,负责人:陈士林