目的：本研究应用ITS2序列鉴定区分络石藤及其习用品广东络石藤、地瓜藤、薜荔藤和扶芳藤。方法：提取以上5种中药基原植物基因组DNA，扩增不同样品的ITS2序列。采用隐马尔科夫模型HMMer进行序列注释，ClustalW法进行序列比对，K2P模型计算种内和种间遗传距离分析，邻接法和最大似然法构建进化树。结果：5个物种的ITS2序列长度各不相同，在220-243bp之间。遗传距离分析显示，5个物种的最大种内遗传距离为0.038，最小种间遗传距离为0.113，最大种内遗传距离大于最小种间遗传距离。同时5个物种可以在进化树上区分开来。结论：ITS2序列可以用于中药络石藤及其习用品的分子鉴定，为准确区分该类药材提供新的技术手段。

This study aimed to distinguish T.jasminoides from Psychotria serpens,Ficus tikoua,Ficus pumila and Euonymus fortune.In the study,DNAs from the original plants were extracted,and sequences of internal transcribed spacer 2(ITS2)were amplified.Hidden Markov model(HMMer)was adopted to annotate the sequences which were aligned with ClustalW method.Interspecific and intraspecific genetic distances were calculated based on K2P model.Finally,Neighbor-joining(NJ)and Maximumlikelihood(ML)phylogenetic trees were built.As a result,it was found that the sequence length of ITS2 varied from 220bp to 243bp.The longest interspecific genetic distance was 0.038,while the shortest intraspecific genetic distance 0.113.The five species were distinguishable in the evolutionary tree.In conclusion,ITS2 barcoding,a new technique for the identification of the five Chinese materia medica was provided,promoting its application in the field of Chinese traditional medicine with strategic significance.

国家自然基金委青年科学基金项目（81402887）基于组合质谱技术与代谢组学方法的中药何首乌体内物质作用组群与肝毒性研究，负责人：徐文；广东省科技厅社会发展领域科技计划（2013B021800236）基于代谢组学的附子毒性研究，负责人：徐文；广东省中医院院内专项（2015KT1817）：岭南中草药DNA条形码分子鉴定和生态适宜性研究，负责人：黄志海。