Rhizosphere microbiome of forest trees is connected to their resistance to soil-borne pathogens

• Published in: Plant and soil Vol. 479; no. 1-2; pp. 143 - 158
• Main Authors: Yu, Li, Zi, Haiyun, Zhu, Hongguang, Liao, Yangwenke, Xu, Xia, Li, Xiaogang
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.10.2022; Springer; Springer Nature B.V
• Subjects: Agriculture; Analysis; Antagonism; Antibiosis; Biomedical and Life Sciences; Coniferous trees; Ecology; Exudates; Exudation; Forest ecosystems; Fungi; Gas chromatography; Life Sciences; Mass spectrometry; Mass spectroscopy; Methods; Microbial activity; Microbiomes; Microbiota; Microbiota (Symbiotic organisms); Microorganisms; Pathogens; Phylogeny; Plant Physiology; Plant resistance; Plant Sciences; Plant species; Research Article; Rhizosphere; Rhizosphere microorganisms; RNA sequencing; rRNA 16S; Soil resistance; Soil Science & Conservation; Soil stresses; Soils; Species; Steering; Terrestrial ecosystems; Trees; China; Forest health; Fungal pathogens; Bio-stress; Root exudates; Microbial community
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-022-05505-2

Background and aims The ability of plants to cope with environmental pressure and the interaction between rhizosphere microorganisms and host trees play an important role in the stability and function of forest ecosystems. Beneficial microbes recruited to the plant rhizosphere and stably associated with tree roots can potentially reduce biotic stress, but microbial interactions involved in coping with pathogen attack are not fully understood. Here, we hypothesized that the composition of the rhizosphere microbiota associated with different tree species can influence plant resistance to the stress from soil-borne pathogens, and investigated the roles of rhizosphere microbiota from four broad-leaved and three coniferous tree species involving in the suppression of soil-borne fungal pathogens. Methods We used two antagonism assays, with and without direct contact to soil-borne fungal pathogens, and assessed the differences in suppression of rhizosphere microbiota among seven tree species. Pyrosequencing of the V3-V4 region of the 16S rRNA gene was performed on rhizosphere microbiota, and root exudates of the trees were analyzed by gas chromatography-mass spectrometry (GC–MS). Results Rhizosphere microbial communities from all seven tree species effectively inhibited the fungal pathogens, nevertheless, there were significant differences in their effectiveness. The dissimilarities in rhizosphere bacterial communities were significantly correlated with phylogenetic distance of trees, accounting for the differences in pathogen suppression. Combined analysis of a random forest model and co-occurrence networks, revealed a potentially cooperative interactions between key groups that were positively associated with inhibition of fungal pathogens in the tree rhizosphere. This process was associated with higher concentration of specific compounds in rhizosphere soil. Conclusions In general, potent inhibitory effects of tree species rhizosphere on pathogens were relevant to the enrichment of such key microbes, as Phycisphaeraceae and Rokubacteria with modulation of the remainder taxa. Therefore, trees benefit steering of their rhizosphere microbiome for maintaining forest health.