目的 采用ITS2 DNA条形码技术，研究雷公藤属3种药用植物的遗传特性，揭示其地理分布格局的形成原因。方法 收集雷公藤属植物28个居群223份样本，提取基因组DNA，扩增ITS2基因序列并测序，并进行遗传多样性分析，绘制失配分布曲线检测群居历史动态变化情况，估算雷公藤属种间、种内群体间和群体内的差异及遗传分化系数。结果 雷公藤属28个居群223份样本共检测到12个碱基突变位点，构成10个单倍型。昆明山海棠Tripterygium hypoglaucum共有7个单倍型，H2～H7为特有单倍型；雷公藤Tripterygium wilfordii共有4个单倍型，H8为特有单倍型；东北雷公藤Tripterygium regelii共有3个单倍型，无特有单倍型；H1为3个物种间的共有单倍型，H9和H10为雷公藤和东北雷公藤共有单倍型。群体遗传多样性分析显示，雷公藤属具有较高的单倍型多态性（H_d＝0.615±0.024）和核苷酸多态性[P_i＝（9.47±0.58）×10⁻³]。群体遗传结构分析显示，雷公藤属的变异主要存在于物种之间（76.14%），种内群体间和群体内的变异分别为11.42%、12.44%。群体动态历史分析表明，雷公藤属、雷公藤和东北雷公藤曾经历过扩张，而昆明山海棠未经历过扩张。结论 雷公藤属及其属下的昆明山海棠和雷公藤的遗传多样性水平较高，而东北雷公藤遗传多样性水平较低。雷公藤属植物在第4纪冰期时，将中国西南、华中和华东的部分地区作为冰期避难所，冰期后以冰期避难所为中心向四周扩散，形成当前雷公藤属植物的分布格局。

Objective To study the genetic characteristics and geographical distribution of three species of the genus Tripterygium by ITS2 DNA barcoding technique. Methods A total of 223 samples from 28 populations of Tripterygium were collected. The genomic DNA extraction and ITS2 gene amplification and sequencing were performed on the above samples. Genetic diversity was analyzed by calculating haplotype diversity and nucleotide diversity. The dynamic change of social history was detected by drawing the curve of mismatch distribution. Based on the above data analysis, the differences among species, populations and populations, and the coefficient of genetic differentiation between species and populations were estimated. Results A total of 12 base mutation sites were detected in 223 samples from 28 populations of Tripterygium, which constituted 10 haplotypes. There were seven haplotypes in Tripterygium. hypoglaucum, and H2—H7 were unique haplotypes. There were four haplotypes in T. wilfordii, and H8 was a unique haplotype. There were three haplotypes in T. regelii. Among the three species, H1 is the haplotype of three species, H9 and H10 are the haplotypes of T. wilfordii and T. regelii. The analysis of population genetic diversity showed that Tripterygium had high haplotype and nucleotide polymorphism[H_d=0.615 ±0.024, P_i=(9.47 ±0.58)×10⁻³]. The analysis of population genetic structure showed that the variation of Tripterygium mainly existed among species (76.14%), and the variation of intraspecies and intrapopulation was 11.42% and 12.44%, respectively. The population dynamic analysis showed that Tripterygium, T. wilfordii and T. regelii had experienced expansion, but T. hypoglaucum had not. Conclusion The genetic diversity level of Tripterygium, T. hypoglaucum and T. wilfordii are higher than that of T. regelii. Tripterygium used parts of Southwest China, Central China, and East China as refuges during the Quaternary ice age. After the ice age, Tripterygium spread around the refuge, forming the current distribution pattern.

R282.12

国家重大新药创制科技专项（2017ZX09101002）；重庆市基础科学与前沿技术研究项目（cstc2017jcyjAX0001，cstc2018jcyjAX0142）；重庆市社会事业与民生保障科技创新专项（cstc2017shms-zdyfX00012）