PT  - JOURNAL ARTICLE
AU  - Benjamin Brachi
AU  - Daniele Filiault
AU  - Hannah Whitehurst
AU  - Paul Darme
AU  - Pierre Le Gars
AU  - Marine Le Mentec
AU  - Timothy C. Morton
AU  - Envel Kerdaffrec
AU  - Fernando Rabanal
AU  - Alison Anastasio
AU  - Mathew S. Box
AU  - Susan Duncan
AU  - Feng Huang
AU  - Riley Leff
AU  - Polina Novikova
AU  - Matthew Perisin
AU  - Takashi Tsuchimatsu
AU  - Roderick Woolley
AU  - Caroline Dean
AU  - Magnus Nordborg
AU  - Svante Holm
AU  - Joy Bergelson
TI  - Plant genetic effects on microbial hubs impact fitness across field trials
AID  - 10.1101/181198
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 181198
4099  - http://biorxiv.org/content/early/2021/05/11/181198.short
4100  - http://biorxiv.org/content/early/2021/05/11/181198.full
AB  - Although complex interactions between hosts and microbial associates are increasingly well documented, we still know little about how and why hosts shape microbial communities in nature. In addition, host genetic effects on microbial communities vary widely depending on the environment, obscuring conclusions about which microbes are impacted and which plant functions are important. We characterized the leaf microbiota of 200 A. thaliana genotypes in eight field experiments and detected consistent host effects on specific, broadly distributed microbial OTU’s. Host genetics disproportionately influenced hubs within the microbial communities, with their impact then percolating through the community, as evidenced by a decline in the heritability of particular OTUs with their distance to the nearest hub. By simultaneously measuring host performance, we found that host genetics associated with microbial hubs explained over 10% of the variation in lifetime seed production among host genotypes across sites and years. We successfully cultured one of these microbial hubs and demonstrated its growth-promoting effects on plants grown in sterile conditions. Finally, genome-wide association mapping identified many putatively causal genes with small effects on the relative abundance of microbial hubs across sites and years, and these genes were enriched for those involved in the synthesis of specialized metabolites, auxins and the immune system. Using untargeted metabolomics, we corroborate the consistent association of variation in specialized metabolites and microbial hubs across field sites. Together, our results reveal that host natural variation impacts the microbial communities in consistent ways across environments and that these effects contribute to fitness variation among host genotypes.Competing Interest StatementThe authors have declared no competing interest.