Bacterial Community Members Increase Bacillus subtilis Maintenance on the Roots of Arabidopsis thaliana

Journal Article · 31 December 2019 · Phytobiomes Journal

DOI: https://doi.org/10.1094/pbiomes-02-20-0019-r · OSTI ID:1802532

Eckshtain-Levi, Noam  ^[1]; Harris, Susanna Leigh ^[2]; Roscios, Reizo Quilat ^[2]; Shank, Elizabeth Anne  ^[3]

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1. Univ. of North Carolina, Chapel Hill, NC (United States); OSTI
2. Univ. of North Carolina, Chapel Hill, NC (United States)
3. Univ. of North Carolina, Chapel Hill, NC (United States); Univ. of Massachusetts Medical School, Worcester, MA (United States)

Plant-growth-promoting bacteria (PGPB) are used to improve plant health and promote crop production. However, because some PGPB (including Bacillus subtilis) do not maintain substantial colonization on plant roots over time, it is unclear how effective PGPB are throughout the plant growing cycle. A better understanding of the dynamics of plant root community assembly is needed to develop and harness the potential of PGPB. Although B. subtilis is often a member of the root microbiome, it does not efficiently monoassociate with plant roots. We hypothesized that B. subtilis may require other primary colonizers to efficiently associate with plant roots. We utilized a previously designed hydroponic system to add bacteria to Arabidopsis thaliana roots and monitor their attachment over time. We inoculated seedlings with B. subtilis and individual bacterial isolates from the native A. thaliana root microbiome either alone or together. We then measured how the coinoculum affected the ability of B. subtilis to colonize and maintain on A. thaliana roots. We screened 96 fully genome-sequenced strains and identified five bacterial strains that were able to significantly improve the maintenance of B. subtilis. Three of these rhizobacteria also increased the maintenance of two strains of B. amyloliquefaciens commonly used in commercially available bioadditives. These results not only illustrate the utility of this model system to address questions about plant–microbe interactions and how other bacteria affect the ability of PGPB to maintain their relationships with plant roots but also may help inform future agricultural interventions to increase crop yields.

• Research Organization: Univ. of North Carolina, Chapel Hill, NC (United States)
• Sponsoring Organization: National Institute of General Medical Sciences; USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0013887; SC0019012
• OSTI ID: 1802532
• Journal Information: Phytobiomes Journal, Journal Name: Phytobiomes Journal Journal Issue: 4 Vol. 4; ISSN 2471-2906
• Publisher: American Phytopathological Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English