生物技术通报 ›› 2026, Vol. 42 ›› Issue (5): 158-173.doi: 10.13560/j.cnki.biotech.bull.1985.2025-0823

• 微生物组学专题 • 上一篇    

不同树龄珙桐根际和根内微生物的群落特征及构建机制

王宇1(), 王毅敏2, 高晗2, 陈邦清1, 彭刚志1, 谭艳1, 郑思怡1, 高本旺1()   

  1. 1.宜昌三峡大老岭自然保护区管理局,宜昌 443000
    2.三峡植物园管理处,宜昌 443000
  • 收稿日期:2025-07-30 出版日期:2026-05-26 发布日期:2026-06-10
  • 通讯作者: 高本旺,男,正高级工程师,研究方向:林木育种及种质资源保护;E-mail: 953146673@qq.com
  • 作者简介:王宇,男,硕士,研究方向:资源利用与植物保护;E-mail: 864336034@qq.com
  • 基金资助:
    2023年中央林业草原生态保护恢复项目(10000017Z175070050001);2024年湖北省林业生态文明建设项目(第三批)(42000021816T300000130)

Characteristics and Assembly Mechanisms of Rhizosphere and Root Endosphere Microbial Communities in Davidia involucrata of Different Ages

WANG Yu1(), WANG Yi-min2, GAO Han2, CHEN Bang-qing1, PENG Gang-zhi1, TAN Yan1, ZHENG Si-yi1, GAO Ben-wang1()   

  1. 1.Dalaoling Nature Reserve Administration of Yichang Three Gorges, Yichang 443000
    2.Three Gorges Botanical Garden Management Office, Yichang 443000
  • Received:2025-07-30 Published:2026-05-26 Online:2026-06-10

摘要:

目的 揭示不同树龄珙桐(Davidia involucrata)根际与根内微生物群落组成、代谢功能及组装机制的动态变化规律。 方法 基于16S rRNA基因和ITS序列扩增子测序技术,分析了不同树龄珙桐(树龄小于50年、50-100年及100年以上)根际和根内微生物群落组成、多样性、与土壤理化因子的相关性、代谢功能特点及群落组成机制。 结果 不同树龄珙桐根际和根内微生物群落α多样性均不存在显著性差异,但根际和根内细菌群落β多样性存在显著性差异。通过LEfSe分析,确定了芽单胞菌门(Gemmatimonadota)、疣微菌门(Verrucomicrobiota)、拟锁瑚菌属(Clavulinopsis)、湿伞属(Gliophorus)、纺锤孢属(Atractospora)等标志性分类单元。不同树龄珙桐根际和根内微生物群落存在一定差异,但优势细菌类群主要为变形菌门(Proteobacteria)、放线菌门(Actinobacteriota),真菌则以子囊菌门(Ascomycota)和担子菌门(Basidiomycota)为主。功能预测表明,细菌核心功能集中于新陈代谢和遗传信息处理,真菌群落则以腐生营养型为主。在二级功能中,根际细菌在异源物质代谢、脂代谢存在显著性差异,根内细菌仅糖链的生物合成与代谢存在显著性差异;根际真菌在植物病原菌和叶腐生菌功能类群差异显著,根内真菌无显著性差异。Mantel test显示,土壤理化因子与微生物群落整体无显著相关性,但酸杆菌门(Acidobacteriota)、绿弯菌门(Chloroflexi)等优势类群与理化因子显著相关。PLS-PM揭示树龄对根内微生物群落的多样性影响更强。群落组装分析证实,根际细菌群落由随机性过程主导,根内细菌群落以确定性过程为主,根际与根内真菌群落均受确定性过程支配。 结论 树龄会对珙桐根际和根内微生物群落及功能产生一定影响,且群落的组装机制会随着树龄的增加呈现动态变化。

关键词: 珙桐, 根际, 内生菌, 群落结构, 功能预测, 群落组装

Abstract:

Objective To elucidate the dynamic changes in composition, metabolic functions, and assembly mechanisms of rhizosphere and root endosphere microbial communities associated with Davidia involucrata across distinct ontogenetic stages. Method Utilizing 16S rRNA gene and ITS amplicon sequencing, we characterized the composition, diversity, functional profiles, assembly mechanisms, and associations with soil physicochemical properties of rhizosphere and root endosphere microbial communities in D. involucrata stratified by age: near-mature forest (tree age <50 years), mature forest (tree age=50–100 years), and ancient forest (tree age >100 years). Result No significant age-dependent differences were detected in microbial alpha diversity within either the rhizosphere or root endosphere. However, bacterial beta diversity presented significant compartmentalization. LEfSe analysis identified several biomarker taxa, including Gemmatimonadota, Verrucomicrobiota, Clavulinopsis, Gliophorus, Atractospora, etc. Although microbial community composition showed variations across age groups, Proteobacteria and Actinobacteriota consistently dominated the bacterial phyla, while Ascomycota and Basidiomycota prevailed among fungi. Core bacterial functional potential was centered on metabolism and genetic information processing, whereas fungal communities were predominantly saprotrophic. Secondary functional analysis revealed significant age-related differences in rhizosphere bacteria for xenobiotic metabolism and lipid metabolism, while root endosphere bacteria differed significantly only in glycan biosynthesis and metabolism. Rhizosphere fungal functional guilds exhibited significant variation, particularly for plant pathogens and leaf saprotrophs, whereas root endosphere fungi showed no significant functional shifts. Mantel tests indicated no overarching correlation between the total microbial community and soil physicochemical factors, although dominant phyla including Acidobacteriota and Chloroflexi demonstrated significant associations. Partial Least Squares Path Modeling (PLS-PM) indicated tree age exerted a stronger influence on root endosphere microbial diversity than on rhizosphere diversity. Community assembly analysis demonstrated that stochastic processes governed rhizosphere bacterial assembly, whereas deterministic processes dominated the assembly of both rhizosphere and root endosphere fungal communities. Conclusion Tree age exerts a discernible influence on the microbial communities and their functions within the rhizosphere and root endosphere of D. involucrata. Furthermore, the mechanisms governing microbial community assembly present dynamic shifts with tree age.

Key words: Davidia involucrata, rhizosphere, root endosphere, community structure, functional prediction, community assembly