Page 178 - 《广西植物》2026年第1期
P. 178
1 7 4 广 西 植 物 46 卷
( 1. Dalaoling Nature Reserve Administration of Yichang Three Gorgesꎬ Yichang 443000ꎬ Hubeiꎬ Chinaꎻ
2. Three Gorges Botanical Garden Management Officeꎬ Yichang 443000ꎬ Hubeiꎬ China )
Abstract: To investigate the characteristics and functional patterns of rhizosphere and root endophytic microbial
communities in different provenances of Davidia involucrataꎬ this study took rhizosphere soil and root tissues as research
materialsꎬ systematically examined community compositionꎬ diversityꎬ physicochemical factor correlationsꎬ co ̄
occurrence networksꎬ and curried out the function prediction through 16S rRNA gene and ITS sequence amplicon
sequencing technology. The results were as follows: (1) No significant α diversity differences were observedꎬ but
distinct β diversity patterns existed between provenances across compartments. ( 2) The dominant bacterial phyla
included Proteobacteriaꎬ Acidobacteriotaꎬ and Actinobacteriotaꎬ while the dominant fungal phyla were Ascomycota and
Basidiomycotaꎻ genus ̄level analysis revealed provenance ̄specific enrichment patterns. ( 3) Co ̄occurrence network
analysis revealed bacterial communities exhibited greater interaction complexity compared to fungiꎬ as evidenced by a
higher average degree and modularity in network topologyꎬ reflecting the greater ecological conservatism of fungal
communities. (4) LEfSe analysis identified 39 bacterial and 30 fungal taxa that demonstrated significant provenance ̄
driven differentiation. (5) Physicochemical factor and microbial community correlation analysis indicated that soil
organic carbon significantly positively correlated with the dominant bacterial communities in rhizosphere soilꎬ while soil
available potassium was significantly positively correlated with endophytic fungal communities within rootsꎬ with no other
physicochemical factor and microbial community correlations observed. ( 6) Functional prediction indicated that
dominant bacteria in the rhizosphere and roots endosphere primarily engage in functions such as metabolismꎬ while fungi
were predominantly saprotrophic. The rhizosphere bacterial communities from the two provenances exhibited significant
differences in 11 functionsꎬ including the biosynthesis of other secondary metabolitesꎬ transcriptionꎬ foldingꎬ sorting and
degradation. For rhizosphere fungiꎬ only the function of lichen symbiotic fungi showed significant differences. In
conclusionꎬ provenance can affect the composition and interactions of microorganismsꎬ and shape differentiated functions
which may influence the ecological adaptability of D. involucrataꎬ thereforeꎬ the findings of this study can provide
theoretical support at the microbiome level for the ex ̄situ conservation of the endangered plant D. involucrata.
Key words: Davidia involucrataꎬ rhizosphereꎬ endophytesꎬ community structureꎬ co ̄occurrence networkꎬ
functional prediction
珙 桐 ( Davidia involucrata) ꎬ 隶 属 于 珙 桐 科 作为植物与土壤的生物媒介ꎬ参与养分循环、抑制
( Davidiaceae) ꎬ珙桐属( Davidia) ꎬ是第三纪古热 病原菌的生长及增强植物抗逆性(Philippot et al.ꎬ
带植物区系的孑遗物种ꎬ天然分布于湖北、湖南、 2009ꎻ Ling et al.ꎬ 2022)ꎮ 植物内生菌则是定殖于
四川、重庆、贵州、云南、陕西和甘肃等地ꎬ主要集 植物组织内部ꎬ通过与宿主互惠共生ꎬ促进植物生
中在海拔 600 ~ 3 200 m 的山地生境ꎬ呈现间断性 长( Benson & Silvesterꎬ 1993ꎻ Luo et al.ꎬ 2011ꎻ
零星分布( 黎云样ꎬ2003) ꎮ 珙桐迁地保育主要依 Khan et al.ꎬ 2012ꎻ Hamilton & Bauerleꎬ 2012 )ꎮ
赖种子萌发和扦插繁殖ꎬ而引种环境适应性问题 因此ꎬ解析植物微生物组成与功能是理解其环境
成为关键制约因素( 张清华等ꎬ2000) ꎮ 目前ꎬ关 适应机制的关键ꎮ 近年来ꎬ组学技术的革新为濒
于珙桐的 研 究 主 要 集 中 在 群 落 分 布 ( 张 燕 等ꎬ 危植物的微生物群落解析提供了新视角ꎮ 阿拉坦
2024ꎻ杨永军等ꎬ2024) 、繁育技术体系( 董嘉明ꎬ 存布尔等(2024)通过研究进一步明确了濒危药用
2024) 、形态特征解剖( 张家勋等ꎬ1994) 及生理 植物掌裂兰根部内生和根际真菌群落组成ꎮ 有研
遗传特性( 关萍等ꎬ2015ꎻ令狐高 曼 等ꎬ2024) 等 究表明ꎬ濒危植物大别山五针松根际微生物与根
方面ꎬ关于植物种源对微生物组影响的研究仍是 内生菌在菌群丰富度、群落结构组成及功能多样
空白ꎮ 性上 均 存 在 差 异 ( 石 水 琴 等ꎬ 2022ꎻ 项 小 燕 等ꎬ
植物根际与内生微生物群落在植物健康与适 2025)ꎮ 此外ꎬYang Y Z 等(2024) 对青海云杉、白
应性中扮演着至关重要的角色ꎮ 植物根际微生物 桦、油茶 3 种林木微生物组学的研究进一步阐释

