基于ITS序列的DNA条形码技术鉴定红豆杉属植物

Identification of Species of Taxus by DNA Barcoding Based on ITS Sequence

DNA条形码技术是一种快速、简便、准确的物种鉴定方法。本研究利用DNA条形码技术对南方红豆杉Taxus wallichiana var.maire样品H1,H2,H3,H4;东北红豆杉T.cuspidata样品D1,D2和欧洲红豆杉T.baccata样品EU1,EU2八个样品的ITS1-18S序列进行PCR扩增和测序,将测序结果与GenBank中的同源序列进行比对分析。结果表明,H1,H2,H3,H4与南方红豆杉的序列相似性最高,D1,D2与东北红豆杉T.cuspidata的序列相似性最高,EU1,EU2与欧洲红豆杉T.baccata的序列相似性最高。用邻接法(NJ)构建ITS1-18S序列的系统进化树(boostrap1000次重复),结果表明,H1,H2,H3,H4和南方红豆杉聚为一枝;D1,D2与东北红豆杉聚为一枝;EU1,EU2与欧洲红豆杉聚为一枝。上述分析结果表明:H1,H2,H3,H4为南方红豆杉;D1,D2为东北红豆杉;EU1,EU2为欧洲红豆杉,与采集地样品信息完全一致。故可以利用引物ITS1-18S从分子水平区分红豆杉属Taxus植物。

Fresh branches of Taxus were collected from 8 trees in Shanghai,Zhejiang and Jiangsu in March 2017.They were PCR amplified and sequenced by DNA barcoding,and the results were compared with the homologous sequences in GenBank.The results showed that 4 samples had the highest sequence similarity with T.wallichiana var.mairei.Two samples had the highest sequence similarity with T.cuspidata,and the other 2 samples with T.baccata.Phylogenetic tree established by neighbor-joining method based on ITS1-18S sequences indicated that 4 samples gathered with T.wallichiana var.mairei,2 samples with T.cuspidat,and 2 samples with T.baccata.Analysis resulted that 4 samples were T.wallichiana var.mairei,2 samples T.cuspidate and 2 samples T.baccata,which were completely consistent with the actual sampling tree species.