基于GenBank核酸数据库ITS2序列鉴定一枝蒿与其混淆品种

目的:利用GenBank核酸数据库中ITS2序列鉴定维吾尔传统药材一枝蒿与其混淆品种。方法:提取一枝蒿药材基因组DNA、扩增ITS2序列并测序,采用CodonCode Aligner V3.0对测序峰图进行校对拼接,并提交至GenBank核酸数据库;运用分析相似性搜索法(BLASTI)进行序列鉴定,下载易混淆品种的ITS2序列,再应用MEGA5.0软件计算种内种间(K2P)遗传距离和构建邻接(NJ)系统聚类树。结果:一枝蒿与其混淆品种之间的K2P遗传距离分布于0.019⁰.254之间,远大于一枝蒿种内遗传距离(0.008);NJ系统聚类树结果表明能将一枝蒿与其混淆品种区分开来,单独聚为一类。结论:ITS2序列适用于维吾尔药材一枝蒿与其混淆品种的鉴别,可为一枝蒿的质量和用药安全提供鉴定依据。

Identification ofArtemisia rupestris and Its Confusable Species Based on GenBank Nucleotide Database ITS2 Sequence

OBJECTIVE： To identify Artemisia rupestris and its confusable species by using GenBank nucleicacid database ITS2 sequence. METHODS： Total genomic DNA was isolated from A. rupestris, and nuclear DNA ITS2 sequences were amplified; DNA sequencing were collated and matched by using CodonCode Aligner V3.0 and submitied to GenBank nucleicacid database. Identification analysis was performed with BLASTI, and ITS2 sequences of confusable species were downloaded. K2P Distances were calculated using MEGA 5.0 software and neighbor-ioining （NJ） phylogenetic tree was established. RESULTS： K2P genetic distance between A. rupestris and confusable species ranged from 0.019 to 0.254, which was far more than intraspecific genetic distance ofA. rupestris（0.008）. Results of NJ phylogenetic tree showed that A. rupestris can be separated from its confusable species and classified into a separate one. CONCLUSIONS： DNA ITS2 sequence is suitable for the identification ofA. rupestris and its confusable species and provides reference for quality and safety identification ofA. rupestris.