基于ITS2序列的柴胡属植物种子的鉴定及遗传多样性分析

Identification and genetic diversity analysis of Bupleurum seed based on ITS2 Sequence

目的:本研究旨在对国家中药种质资源库收集的41份柴胡属植物种子进行分子鉴定,验证ITS2序列对柴胡属植物种子的鉴定能力,并分析柴胡属植物的遗传多样性。方法:应用ITS2序列测定样品种子的DNA序列,从分子角度鉴定柴胡属种子的物种,并构建系统聚类树,分析其遗传多样性。结果:鉴定出8种柴胡属植物的种子,2种非柴胡属植物的种子,测得的所有种子DNA序列的GC量在53.9%-57.0%,平均为55.7%,变异位点数202个,K2P遗传距离为0-1.460,构建出UPGMA聚类树。结论:基于ITS2序列的分子鉴定方法可成功鉴别柴胡属药用植物及其混淆品的种子,是一种操作方便,准确性高、鉴定效果好的鉴定方法。柴胡属植物物种内及物种间具有丰富的遗传多样性,相同物种间的遗传变异相对稳定,种质及生态环境对柴胡属药用植物的遗传变异有较大的影响。

Objective:The aim of this study was to identify 41 species of Bupleurum seeds from the state seed bank,verify the sequencing ability of ITS2 sequences on Bupleurum plants,and analyze the genetic diversity of Bupleurum plants.Method:The DNA sequence of sample seeds was detected by ITS2 sequence.The species of Bupleurum seeds were identified from molecular point of view,and the system clustering tree was constructed to analyze its genetic diversity.Result:The seeds of 8 species of Bupleurum and 2 seeds of non-Bupleurum plants were identified.The GC content of all seed DNA sequences was 53.9%-57.0%,with an average of 55.7%and 202 sites of variation.The K2P genetic distance was 0-1.460,and the UPGMA clustering tree was constructed.Conclusion:The molecular identification method based on ITS2 sequence can successfully identify the seeds of Bupleurum and its adulterants,which is a convenient,accurate and effective method.There are abundant genetic diversity within and among species of Bupleurum,and the genetic variation among the same species is relatively stable.Germplasm and ecological environment have great influence on genetic variation of Bupleurum plant.