Transmission of synthetic seed bacterial communities to radish seedlings: impact on microbiota assembly and plant phenotypeuse asterix (*) to get italics

Marie Simonin, Anne Preveaux, Coralie Marais, Tiffany Garin, Gontran Arnault, Alain Sarniguet, Matthieu BarretPlease use the format "First name initials family name" as in "Marie S. Curie, Niels H. D. Bohr, Albert Einstein, John R. R. Tolkien, Donna T. Strickland"

2023

<p style="text-align: justify;">Seed-borne microorganisms can be pioneer taxa during germination and seedling emergence. Still, the identity and phenotypic effects of these taxa that constitute a primary inoculum of plant microbiota is mostly unknown. Here, we studied the transmission of bacteria from radish seeds to seedlings using the inoculation of individual seed-borne strains and synthetic communities (SynComs) under in vitro conditions. The SynComs were composed of highly abundant and prevalent, sub-dominant or rare bacterial seed taxa. We monitored the transmission of each strain alone or in communities using gyrB gene amplicon sequencing and assessed their impacts on germination and seedling phenotype.</p> <p style="text-align: justify;">All strains and SynComs successfully colonized seedlings and we were able to reconstruct a richness gradient (6, 8 and 12 strains) on both seeds and seedlings. Stenotrophomonas rhizophila became dominant on seedlings of the three SynComs but most strains had variable transmission success (i.e increasing, stable or decreasing during seed to seedling transition) that also depended on the SynCom richness.</p> <p style="text-align: justify;">Most individual strains had no effect on seedling phenotypes, at the exception of <em>Pseudomonas viridiflava</em> and <em>Paenibacillus sp</em>. that had detrimental effects on germination and seedling development. Abnormal seedling morphologies were also observed with SynComs but their proportions decreased at the highest richness level. Interestingly, some bacterial strains previously identified as core taxa of radish seeds (<em>Pseudomonas viridiflava</em>, <em>Erwinia persicina</em>) were associated with detrimental effects on seedling phenotypes either in isolation or in SynComs. These results confirm that the plant core microbiome includes pathogenic and not only commensal or mutualistic taxa.</p> <p style="text-align: justify;">Altogether, these results show that SynCom inoculation can effectively manipulate seed and seedling microbiota diversity and thus represents a promising tool to better understand the early stages of plant microbiota assembly. This study also highlights strong differences between native seed-borne taxa in the colonization and survival on plant habitats.</p>

https://www.ebi.ac.uk/ena/browser/view/PRJEB58635You should fill this box only if you chose 'All or part of the results presented in this preprint are based on data'. URL must start with http:// or https://

https://github.com/marie-simonin/Radish_SynComYou should fill this box only if you chose 'Scripts were used to obtain or analyze the results'. URL must start with http:// or https://

Plant microbiota, Seed-borne bacteria, Core microbiota, Synthetic community, Phytobiome, Pathobiome

NonePlease indicate the methods that may require specialised expertise during the peer review process (use a comma to separate various required expertises).

Microbe-microbe and microbe-host interactions, Microbial ecology and environmental microbiology, Microbiomes

Itumeleng Moroenyane, Corinne Walsh corinne.walsh@colorado.edu No need for them to be recommenders of PCIMicrobiol. Please do not suggest reviewers for whom there might be a conflict of interest. Reviewers are not allowed to review preprints written by close colleagues (with whom they have published in the last four years, with whom they have received joint funding in the last four years, or with whom they are currently writing a manuscript, or submitting a grant proposal), or by family members, friends, or anyone for whom bias might affect the nature of the review - see the code of conduct

Gabriele Berge.g. John Doe [john@doe.com]

2023-02-15 10:27:26

Sebastien Massart