目的:对龙葵及其近缘种进行ITS2分子鉴定,确保药材质量和临床安全用药。方法:收集各产区的不同基原龙葵及其近缘种共61份样品,采用DNA试剂盒提取方法,提取DNA,经PCR扩增后测序,采用Codon Code Aligner V5.1.2对测序序列进行峰图质量分析,基于MEGA5.1中的K2P模型计算龙葵及其近缘种的种内、种间遗传距离及构建系统聚类树。结果:龙葵及近缘种的DNA提取率为100%,龙葵两个基原的ITS2序列长度均为210 bp,ITS2序列变异较小。龙葵与少花龙葵的ITS2序列与其近缘种的最大种内距离均小于与其近缘种的最小种间距离。基于ITS2序列构建NJ树,龙葵、少花龙葵各自聚为一支,并且与其他近缘种明显分开。同时基于条形码鉴定标准操作流程成功将药材市场购买的龙葵药材进行鉴定,购买的22份龙葵药材样品中只有2份鉴定为龙葵,2份鉴定为少花龙葵,其余均为红果龙葵。结论:药材市场上龙葵药材掺伪情况严重,基于ITS2序列能够准确鉴定龙葵及其近缘种,确保临床安全用药。 Objective: To identify ITS2 of Solanum nigrum and its related species to ensure the quality of medicinal materials and clinical safety. Methods: Totally 61 samples of different Solanum nigrum and its related species were collected from different producing areas. The DNA was extracted by DNA kit. The DNA was extracted and sequenced by PCR amplification. The sequences were sequenced by Codon Code Aligner V5.1.2 Based on the K2P model in MEGA5.1, the intraspecific and interspecific genetic distances of Solanum nigrum and its related species were calculated and the phylogenetic tree was constructed. Results: The DNA extraction rate was 100% for Solanum nigricifera and its related species. The lengths of ITS2 sequences of two somatic bases of Solanum nigrum were both 210 bp and the variations of ITS2 sequences were small. The maximum intraspecific distance between ITS2 sequences of Solanum nigrum and its relatives was less than that between its closest species. NJ tree was constructed based on ITS2 sequence, and Solanum nigrum and Solanum nigrum were clustered into one and separated from other related species. At the same time, based on the standard operation procedure of barcode identification, the Solanum nigricans medicinal herbs purchased from the medicinal herbs market were successfully identified. Only 2 of the 22 sojae samples purchased were identified as Solanum nigrum, 2 were identified as Solanum nigrum, sunflower. Conclusion: Solanum nigrum is adulterated in the medicinal herbs market. Based on ITS2 sequence, the identification of Solanum nigrum and its related species can be accurately identified to ensure clinical safety.