连作对白花泡桐生长及根内外微生物群落的影响  

Effects of continuous cropping on the growth and endophyte and rhizosphere microbial community structure of Paulownia fortunei

作　　者：赵振利[1] 李慧珂 李烜桢[1] 范国强[1] ZHAO Zhenli;LI Huike;LI Xuanzhen;FAN Guoqiang(College of Forestry,Henan Agricultural University,Zhengzhou,Henan 450046,China)

机构地区：[1]河南农业大学林学院,河南郑州450046

出　　处：《森林与环境学报》2023年第4期407-415,共9页Journal of Forest and Environment

基　　金：国家重点研发计划项目“高效农桐复合经营技术研究”(2017YFD060050604)。

摘　　要：为了弄清连作对白花泡桐生长的影响及其根内和根际微生物群落的变化情况,以连续种植1~3 a的白花泡桐为研究对象,基于16S rRNA和内源转录间隔区(ITS)高通量测序技术,分析不同连作条件下根内和根际微生物群落的结构变化。结果表明:连作显著影响了白花泡桐的生长,尤其表现在株高的降低,其次还导致了白花泡桐叶片数的减少和叶片的变窄。不同树龄的白花泡桐根内细菌主要为变形菌门(Proteobacteria)和厚壁菌门(Firmicutes)细菌,根内真菌主要为子囊菌门(Ascomycota)和担子菌门(Basidiomycota)真菌,根际细菌主要为放线菌门(Actinobacteriota)、变形菌门、酸杆菌门(Acidobacteriota)和绿屈挠菌门(Chloroflexi)细菌,根际真菌主要为子囊菌门、被孢菌门(Mortierellomycota)和担子菌门真菌。连作降低了白花泡桐根内细菌和真菌的Chao1指数,改变了根内和根际细菌和真菌的群落结构。此外,白花泡桐连作提高了根内真菌病理-腐生营养型、病理-腐生-共生营养型和腐生营养型等功能的相对丰度,降低了根内和根际共生营养型相对丰度。细菌-真菌共存网络分析发现,白花泡桐存在一个根际核心微生物群落,其中,植物病原菌镰刀菌(Fusarium)的相对丰度随树龄的增加而提高,植物有益菌假单胞菌属(Pseudomonas)的相对丰度随树龄的增加而呈先升高后降低的趋势。综上,白花泡桐连作引起了根内细菌和真菌的多样性降低、根内和根际细菌和真菌的群落结构功能改变、根际镰刀菌大量增殖,这可能是造成白花泡桐连作障碍的主要原因。To understand the effects of continuous cropping on the growth of Paulownia paulownia and microbial community changes of its roots and rhizosphere,P.fortunei saplings that were cultivated using continuous cropping for 1-3 years were analyzed using 16S rRNA and ITS gene high⁃throughput sequencing technology to examine the community structure of bacteria and fungi communities in the root and rhizosphere of the selected plants.The analysis indicated that,for all the selected P.fortunei plants,Proteobacteria and Firmicutes were the main bacteria in the root,while Ascomycota and Basidiomycota were the main fungi.The main rhizosphere bacteria were Actinobacteriota,Proteobacteria,Acidobacteriota,and Chloroflexi,whereas the main rhizosphere fungi were Ascomycota,Mortierellomycota,and Basidiomycota.Continuous cropping decreased the Chao1 index of the bacteria and fungi in the roots and altered the community structure of the rhizosphere microbial community.In addition,continuous cropping increased the abundances of the pathotroph⁃saprotrophic,pathotroph⁃saprotroph⁃symbiotrophic,and saprotrophic fungi in the roots,and decreased the abundances of symbiotrophic fungi in roots and rhizosphere.Notably,the analysis of bacteria⁃fungi coexistence network revealed a core rhizosphere microbial community,in which the abundance of the plant pathogen,Fusarium,increased as the trees aged.Alternatively,the abundance of plant beneficial bacteria,Pseudomonas,increased initially,but subsequently decreased as the trees grew older.Collectively,continuous cropping can cause growth disorders in P.fortunei,alters the structure and function of the bacterial and fungal communities in the tree′s root and rhizosphere,and allows for the proliferation of Fusarium in the rhizosphere;thereby,negatively affecting the cultivation of P.fortunei.

关 键 词：白花泡桐 连作障碍 植物病原菌 16S rRNA 高通量测序 根际 微生物群落 

分 类 号：S763[农业科学—森林保护学]