基于ITS2条形码的南药巴戟天真伪鉴别

本研究旨在建立基于ITS2条形码的巴戟天及其混伪品的真伪鉴别方法。采用试剂盒提取巴戟天植物样品的总DNA,以一对通用引物对其ITS2条形码进行PCR扩增并测序;从Genbank数据库获取巴戟天及其混伪品ITS2序列。采用DNAMAN、ClustalX软件拼接比对序列,以及利用MEGA5.1软件构建NJ树。获得的22条ITS2序列的长度范围为224~244 bp,GC含量范围为59.8%~70.1%。巴戟天与8种混伪品的ITS2序列存在155处变异,种间K2P遗传距离远大于种内K2P遗传距离。基于ITS2条形码的NJ聚类树能直观地区分巴戟天及其混伪品。因此,ITS2条形码适用于南药巴戟天及其混伪品的鉴别,可为其基原研究提供重要的分子鉴定证据。

IdentifyingMorinda officinalis and Its Adulterants Based on ITS2 Barcode

The study aimed to establish a novel identification method for Morinda officinalis and its adulterants based on ITS2 barcode. Genomic DNA was extracted from M. officinalis leaves kept in gel and ITS2 region was amplified and sequenced with a pair of universal primers. ITS2 sequences of M. officinalis and its adulterants acquired from plant materials and Genbank were assembled and aligned by DNAMAN and CLUSTALX, and the NJ tree was constructed using MEGA 5.1. Significant differences were observed in the ITS2 sequences between M. officinalis and its adulterants. The interspecific genetic distance was far more than the intraspecific distance. NJ tree based on ITS2 sequences can distinguish M. officinalis and its adulterants intuitively. Therefore, ITS2 barcode could be used to identify M. officinalis and its adulterants effectively, and provide important molecular evidence for the authentication of germplasm resources.