Location: Integrated Cropping Systems ResearchTitle: Synthetic microbial consortia derived from rhizosphere soil protect wheat against a soilborne fungal pathogen
Submitted to: Frontiers in Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/11/2022
Publication Date: 8/31/2022
Citation: Yin, C., Hagerty, C., Paulitz, T.C. 2022. Synthetic microbial consortia derived from rhizosphere soil protect wheat against a soilborne fungal pathogen. Frontiers in Microbiology. 13. Article 908981. https://doi.org/10.3389/fmicb.2022.908981.
Interpretive Summary: Microbial communities play vital roles in building soil and influencing plant growth and development. Specific microorganisms have been shown to promote plant growth, protect plants from pathogen infection, or provide nutrition for plants. There is interest in adding select microbes or mixtures of microbes to the soil to provide these benefits. However, more information is needed regarding the activity and stability of these microorganisms in soils and plants before this approach can be developed for practical application. In this study, we characterized a collection of bacteria previously isolated from the root zone of wheat and evaluated their activity against fungal pathogens in the soil. We found that four combinations of different compositions of these bacteria enhanced the resistance of wheat to fungal pathogens. We also characterized the biochemical mechanisms by which these bacteria affected plant health. These results can be used by researchers to further evaluate the use of microbial inoculants to enhance crop resiliency against disease and other stresses.
Technical Abstract: Synthetic microbial communities (SynComs) could potentially replace some functions of the plant microbiome and emerge as a promising inoculant for improving crop performance. Here, we characterized a collection of bacteria, previously isolated from the wheat rhizosphere, for antifungal activity against soilborne fungal pathogens. Fourteen isolated rhizobacteria displayed antifungal activities against Rhizoctonia solani AG8 (AG8) in vitro and/or in vivo. Subsequently, ten SynComs with different compositions from fourteen bacterial strains were created. Four of them significantly enhanced wheat performance upon AG8 infection, compared to the corresponding individual bacteria. Further, the mechanisms of interaction of the tested bacteria with each other and plants were explored. We found that nine individuals and nine SynComs impacted the root architecture of Arabidopsis by producing indole acetic acid (IAA). Nine individuals and six SynComs significantly inhibited the growth of AG8 via producing volatiles. The cell-free supernatants from six individuals inhibited the growth of AG8. Together, this study provided the potential for improving crop resilience by designing SynComs.