目的 基于ITS1和ITS2序列，对来自四川、青海、甘肃和西藏不同地区的甘松属植物甘松Nardostachys chinensis、匙叶甘松N. jatamansi遗传多样性进行研究及分子鉴定。方法 通过PCR扩增获得甘松ITS1、ITS2序列，采用MEGA软件进行多重序列比对，用DNA EditSeq软件进行剪切、拼接和统计等分析，运用Kimura two-parameter（K2-P）模型进行遗传距离分析，运用DNASTAR软件进行同源性和差异性分析，利用邻接法（neighbor joining，NJ）构建系统发育树，采用DNAsp V5软件进行遗传多样性分析。结果 ITS1序列长度范围为687～689 bp，仅2 bp差异；ITS2序列长度高度保守，均为468 bp。ITS1与ITS2序列G/C含量均达66.00%以上。系统发育分析发现，ITS序列可将甘松属20个样本分为2支，甘松与匙叶甘松各自为一支，但二者亲缘关系很近。遗传多样性分析发现，匙叶甘松综合遗传多样性水平指标大于甘松。结论 据形态学及遗传学分析，甘松属应分为甘松与匙叶甘松2种，且遗传多样性较低，种内遗传变异相对稳定。ITS序列可用于甘松属品种的鉴定。研究结果可以为甘松属植物资源分类、评价、保护与可持续利用提供一定的理论基础。

Objective Based on the ITS1 and ITS2 sequences, we studied the genetic diversity and molecular identification of the Nardostachys chinensis and N. jatamansi from different regions of Sichuan, Qinghai, Gansu and Tibet. Methods ITS1 and ITS2 sequences of Nardostachys were obtained by PCR amplification; MEGA software was applied for multiple alignment; DNA EditSeq software was used for cutting, splicing and statistical analysis; Kimura two-parameter (K2-P) model was used for genetic distance analysis; DNASTAR software was used for homology and difference analysis; Neighbor joining (NJ) method was used to construct phylogenetic trees and DNAspV5 was used to analysed genetic diversity. Results The ITS1 sequences ranged from 687 to 689 bp, with only 2 bp difference; the ITS2 sequences were highly conserved with 468 bp length, and the G/C content of both ITS1 andITS2 sequences reached over 66.00%. Phylogenetic analysis revealed that the ITS sequences could divide the 20 samples of Nardostachys into two branches,N. chinensis and N. jatamansi, but they were closely related to each other. The genetic diversity analysis showed that the comprehensive genetic diversity index of N. jatamansi was higher than that of N. chinensis. Conclusion According to the morphological and genetic analysis, the Nardostachys should be divided into two species of N. chinensis and N. jatamansi, and the genetic diversity was low, and the intraspecific genetic variation was relatively stable. The ITS sequences can be used to identify the species of Nardostachys. The results of the study can provide a theoretical basis for the classification, evaluation, conservation and sustainable use of plant resources of the Nardostachys.

项目基金：国家重点研发计划（2018YFC1706101）；四川省自然科学基金项目（青年科学基金项目-2022NSFSC1588）； 2021年国家民委领军人才支持计划；西南民族大学双一流项目（CX2023053）