Host-microbes interactions play crucial roles in organisms' biological and ecological function, thus organisms are better considered as a complex functional unit composed by the host and the associated microorganisms, including bacteria, called holobiont.
Seagrasses are marine flowering plants and harbor different epiphytic microbial communities on their aboveground and belowground compartments and potentially within their roots tissues with which they may establish symbiotic relationships.
Microbes enhance the availability of the nutrients, which can limit seagrass growth and primary production, protect seagrass detoxifying the surrounding environment, and seagrasses, in turn, constitute diverse chemical microenvironments and an organic carbon enriched habitat for the epiphytic microbes.
Despite the important role of the seagrass-microbes interactions in the seagrass ecology,
many aspects of this relationship have not been clarified yet, including those related to the establishment of the symbiosis, to the driving factors that shape the microbial community, whereas the contribution of the environmental conditions rather than the host species. In this work, the epiphytic microbial community associated with two different seagrass species under the same environmental conditions was investigated. Specifically, the comparison is between the endemic and climax species Posidonia oceanica and the invasive and ephemeral Lessepsian migrant Halophila stipulacea.
Within the Mediterranean Sea, the two species can be found growing side by side, thus, exposed to the same environmental pressures, to which they might respond differently according to their ecological capabilities.
Contrasting the environmental and the epiphytic microbial communities associated with the two seagrass species, it is evaluated whether the host species and, even more, their characteristics (i.e., the plant structure or its chemical properties) rather than the environmental conditions shape the microbial epiphytic community.
Moreover, the comparison between the two seagrass species aims to evaluate whether the epiphytic microbial communities may enhance the seagrass adaptation to the environment and potentially, enhance the invasive capabilities of Halophila stipulacea.
Understanding how the seagrass holobiont changes in natural conditions it is pivotal to unrevealing what shapes and regulates these interactions. This knowledge may help to enhance seagrass monitoring, conservation, and the related ecosystem process. Less...