A highly conserved core bacterial microbiota with nitrogen-fixation capacity inhabits the xylem sap in maize plants (Nature Comms)

Plants and microorganisms build complex associations that are essential for plant homeostasis. Studies have suggested that there is a ‘core microbiota’ that is particular to specific crops and that is inherited through generations. Targeted manipulation of crop microbiomes with the inoculation of synthetic communities (SynCom) seems to be a promising tool to develop sustainable crop production in the future. In this work, Zhang et al. determined that maize has different core microbiomes in different compartments, with the one from the xylem being most conserved. 25 Operational Taxonomic Units (OTUs) were found in all the xylem sap samples and the culturable ones were able to fix nitrogen (Biological N-fixation, BNF). This finding was verified by the use of GFP-tagged strains for the colonization of the xylem sap and stem and by the use of the ¹⁵N isotopic dilution method. In conclusion, maize xylem sap core microbiota is conserved across genotypes and environmental conditions and it contributes to plant N-nutrition through BNF. Understanding core microbiota is a promising tool to enhance crop performance in sustainable agriculture. (Summary by Eva Maria Gomez Alvarez, @eva_ga96) Nature Comms. 10.1038/s41467-022-31113-w