目的 发掘与柴胡皂苷含量显著关联的关键细菌类群。方法 分别采集北柴胡Bupleurum chinense、三岛柴胡B. falcatum和狭叶柴胡B. scorzonerifolium的根际和根表土壤样本及根系样本，提取总DNA后进行宏基因组分析，采用UPLC-MS测定3种柴胡根部柴胡皂苷A（saikosaponin A，SSA）、柴胡皂苷B₂（saikosaponin B₂，SSB₂）、柴胡皂苷B₄（saikosaponin B₄，SSB₄）、柴胡皂苷C（saikosaponin C，SSC）、柴胡皂苷D（saikosaponin D，SSD）、柴胡皂苷E（saikosaponin E，SSE）和柴胡皂苷F（saikosaponin F，SSF）的含量，利用Pearson识别柴胡药效成分与优势菌种之间的显著关系。结果 柴胡皂苷D在7种柴胡皂苷中含量最高，其平均含量在北柴胡、三岛柴胡和狭叶柴胡中分别为217.5、116.75、139.7 μg/g。柴胡皂苷E和SSF在三岛柴胡中含量最低。宏基因组测序共鉴定出5 440个细菌OTUs。北柴胡的根表、根际和内生部位特有OTUs数量依次为127、126和110；三岛柴胡分别为91、74和69；狭叶柴胡为43、137和126。固氮菌属Azotobacter chroococcum在北柴胡和狭叶柴胡的根际为优势菌，链孢菌属Streptomyces为三岛柴胡根际核心类群。克雷伯氏菌属Klebsiella sp.与假单胞菌属Pseudomonas分别在北柴胡和三岛柴胡的根表及内生部位显著富集。相关性网络鉴定出克雷伯氏菌、纤维单胞菌Cellulomonas sp.和圆褐固氮菌与SSA、SSB₂、SSB₄和SSD的含量呈极显著正相关。结论 阐明柴胡基因型可能通过生态位构建塑造特异性细菌群落，进而促进柴胡皂苷积累。

Objective To identify key bacterial taxa associated with saikosaponins content. Methods Rhizosphere soil, root surface soil, and root samples of Bupleurum chinense, B. falcatum, and B. scorzonerifolium were collected. Total DNA was extracted for metagenomic analysis, and UPLC-MS was used to determine the contents of saikosaponin A (SSA), saikosaponin B₂(SSB₂), saikosaponin B₄ (SSB₄), saikosaponin C (SSC), saikosaponin D (SSD), saikosaponin E (SSE), and saikosaponin F (SSF) in the roots. Pearson correlation analysis was then employed to identify significant relationships between these medicinal components and the dominant bacterial species. Results SSD exhibited the highest content among the seven saikosaponins analyzed, with average concentrations of 217.5 μg/g in B. chinense, 116.75 μg/g in B. falcatum, and 139.7 μg/g in B. scorzonerifolium. B. falcatum had the lowest content of SSE and SSF. Metagenomic sequencing identified a total of 5 440 bacterial OTUs. The numbers of unique OTUs in the root surface, rhizosphere, and endophytic compartments were 127, 126, and 110 for B. chinense; 91, 74, and 69 for B. falcatum; and 43, 137, and 126 for B. scorzonerifolium, respectively. Azotobacter chroococcum was dominant in the rhizosphere of B. chinense and B. scorzonerifolium, whereas Streptomyces was the core taxon in the rhizosphere of B. falcatum. Klebsiella sp. and Pseudomonas were significantly enriched in the root surface and endophytic niches of B. chinense and B. falcatum, respectively. The Klebsiella sp., Cellulomonas sp., and Azotobacter chroococcum were also a highly significant positive correlated with the contents of SSA, SSB₂, SSB₄, and SSD, among the correlation network analysis. Conclusion This study revealed that Bupleurum genotype might drive saikosaponins accumulation by niche construction of specific microbial communities.

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西藏自治区重点研发计划（XZ202401ZY0020）；药用植物种质资源库建设（2021-I2M-1-032）；国家岗位产业体系专家项目（CARS-21）；四川省区域创新合作项目（2026YFHZ0163）