Variation in the bacteriome of the tropical liverwort, Marchantia inflexa, between the sexes and across habitats

Plant-microbe interactions impact ecosystem function through nutrient cycling, community interactions, and individual costs/benefits to the organisms involved. However, information on the establishment, diversity, and function of plant-microbe interactions remains limited, especially for non-vascular plants. We hypothesized that variation in the environment and sex of a host plant, impact the composition and diversity of associated microbial communities. To test this hypothesis, we characterized the bacteriome of the non-vascular plant, Marchantia inflexa, in both males and females across multiple habitats by targeted sequencing of the bacterial 16S rRNA gene. We describe the bacteriome for M. inflexa, and find that it is abundant and diverse, showing some similarities with other non-vascular plant lineages. Using these data, we detected a habitat specific component of the bacteriome, and sex differences in the bacteriome under common garden conditions. On the basis of known microbial functions, our analyses suggest that the specific taxonomic assemblages of bacteria detected in particular habitat types may serve functional roles; allowing plants to better acclimate to their local environment, and that sex differences in the bacteriome may correspond to subtle differences in the physiology and morphology of the sexes. Our initial characterization of variation in bacteriome composition of this tropical liverwort lineage provides valuable information for better understanding the patterns of plant-microbe interactions across land plants.