旋覆花属8种药用植物ITS2序列分析

ITS2 sequence analysis of eight medicinal plants in Inula L.

目的对旋覆花属8种药用植物进行ITS2序列分析，为其分子鉴定提供依据。方法对4种旋覆花属药用植物的8个样本ITS2序列进行PCR扩增和测序，同时从GenBank下载13个样本。用MEGA5．0计算其种间、种内的K2P距离，及各序列变异位点并进行聚类分析。结果旋覆花属8种药用植物ITS2的长度为210-212bp，变异位点为60个；旋覆花药材2种不同来源药用植物有3个变异位点，与其他同属6种植物有13-43个变异位点；构建的系统发育树显示旋覆花药材的不同基原样本各聚为一支，能很好与其他6种植物区分；旋覆花Inula japonica、欧亚旋覆花I.britannica、总状土木香I.racemosa、土木香I.helenium4个物种的遗传距离值远小于其与羊耳菊I.cappa、赤茎羊耳菊I.rubricaulis、显脉旋覆花I.nervosa、泽兰羊耳菊I.eupatoerioides4个物种的遗传距离值。结论ITS2序列能够为旋覆花属8种药用植物的鉴定和Flora of China对羊耳菊、赤茎羊耳菊、显脉旋覆花、泽兰羊耳菊分类修订提供一定的分子证据。

Objective To provide evidence for the molecular identification of eight medicinal plants in Inula L. Methods Eight ITS2 sequence samples of four species in Inula L. were PCR amplified and sequenced, and 13 samples from the GenBank were downloaded. The intra-specific and inter-specific K-2P distances were calculated, and duster analysis was constructed by MEGA 5.0. Results The length of ITS2 region varied from 210--212 bp with 60 variable sites. Inulae Flos from two different sources had three variable sites and its sibling species had 13--43 ones. Different samples of Inula japonica and I. britannica were gathered together and could be distinguished from its six sibling species by UPGMA tree. The genetic distances of four species among I. japonica, L britannica, L helenium, and L racemosa were far less than those of four other species among L cappa, L rubricaulis, Lnervosa, and Leupatoerioides.Conclusion The ITS2 sequence provides the molecular evidence for the identification of eight species of medicinal plants in Inula L. and taxonomic revision of I. cappa, I. rubricaulis, I. nervosa, and I. eupatoerioides in Flora of China.