title: Rhizosphere Microbiomes of European + Seagrasses Are Selected by the Plant, But Are Not Species Specific.
abstract: Seagrasses are marine flowering plants growing in soft-body sediments of intertidal and shallow sub-tidal zones. They play an important role in coastal ecosystems by stabilizing sediments, providing food and shelter for animals, and recycling nutrients. Like other plants, seagrasses live intimately with both beneficial and unfavorable microorganisms. Although much is known about the microbiomes of terrestrial plants, little is known about the microbiomes of seagrasses. Here we present the results of a detailed study on the rhizosphere microbiome of seagrass species across the North-eastern Atlantic Ocean: Zostera marina, Zostera noltii, and Cymodocea nodosa. High-resolution amplicon sequencing of 16S rRNA genes showed that the rhizobiomes were significantly different from the bacterial communities of surrounding bulk sediment and seawater. Although we found no significant differences between the rhizobiomes of different seagrass species within the same region, those of seagrasses in different geographical locations differed strongly. These results strongly suggest that the seagrass rhizobiomes are shaped by plant metabolism, but not coevolved with their host. The core rhizobiome of seagrasses includes mostly bacteria involved in the sulfur cycle, thereby highlighting the importance of sulfur-related processes in seagrass ecosystems.
authors.affiliation: Microbial Systems Ecology, Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam Amsterdam, Netherlands.
authors.forename: Catarina
authors.initials: C
authors.lastname: Cúcio
authors.affiliation: Marine Ecology and Evolution Research Group, Centro de Ciencias do Mar, Universidade do Algarve Faro, Portugal.
authors.forename: Aschwin H
authors.initials: AH
authors.lastname: Engelen
authors.affiliation: Microbial Ecology and Evolution Research Group, Centro de Ciencias do Mar, Universidade do Algarve Faro, Portugal.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Costa
authors.affiliation: Microbial Systems Ecology, Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam Amsterdam, Netherlands.
authors.forename: Gerard
authors.initials: G
authors.lastname: Muyzer
keywords: 16S rRNA; amplicon sequencing; marine bacteria; plant–microbe interactions; rhizosphere; seagrass microbiome; sulfur bacteria; sulfur cycle