基于条形码ITS2序列的何首乌及其近缘种和混淆品的分子鉴别

目的:通过内转录间隔区2(internal transcribed spacer 2,ITS2)序列分析,探究鉴别何首乌与其近缘种和混淆品的新方法。方法:何首乌与其近缘种和混淆品的ITS2序列进行扩增、纯化、测序,运用Seqman软件进行序列拼接,通过MEGA6.0软件进行序列的分析并构建kimura 2-parameter(K2P)模型的neighbor-joinin(NJ)系统聚类树。结果:何首乌与其近缘种和混淆品ITS2序列间存在明显差异,种内遗传距离小于种间遗传距离。齿叶蓼与何首乌种间遗传距离较大,却与翼蓼非常接近,二者的遗传距离仅0.029。NJ系统聚类树显示不同产地的何首乌聚为一支,与其近缘种和混淆品可很好地区分。结论:ITS2序列可有效地鉴别何首乌与其近缘种和混淆品,为何首乌的用药安全性提供技术保障。

Molecular Identification of Fallopia multiflora from Its Closely Related Species and Adulterants Based on Internal Transcribed Spacer 2 Barcode

Objective: To explore a new method for identifying Fallopia multiflorum from its closely related species and adulterants by internal transcribed spacer 2 (ITS2) regions. Method: ITS2 regions of F. multiflora and its closely related species,adulterants were amplified,purified and sequenced.Sequences were assembled by Seqman and analysed by MEGA6.0,neighbor-joining (NJ) phylogenetic tree was constructed based on Kimura 2-parameter (K2P) model. Result: ITS2 regions of F. multiflorumexhibited obvious differences with its closely related species and adulterants.Intraspecific variation was less than interspecific genetic distance.All samples of F. multiflorum showed monophyletic on NJ tree,they could be distinguished from its closely related species and adulterants. Conclusion: ITS2 can be used as a effective marker for identifying F. multiflorum from its closely related species and adulterants,it can provide technical support for drug safety of F. multiflorum.