Fungal communities associated with the seagrass Enhalus acoroides

Marine fungal biodiversity remains vastly understudied, and even less is known known of their biogeography and the process that are responsible for creating these patterns in marine environments. We investigated the fungal communities associated with the seagrass Enhalus acoroides collected from Singapore and Peninsular Malaysia to test the null hypothesis that fungal communities are homogeneous throughout the study area. Collected seagrasses were separated into different structures (leaves, roots, and rhizome) and a sediment sample was collected in close proximity to all plant samples. Amplicon sequencing of the fungal internal transcribed spacer 1 (ITS1) and subsequent analysis revealed significant differences in fungal communities collected from different locations and different structures. We show a significant pattern of distance decay with samples collected close to each other having more similar fungal communities in comparison to those that are more distant, this suggests dispersal limitations along with differences in habitat type are likely contributing to the biogeographic patterns we observe. Our work has implications for seagrass management and restoration initiatives, we recommend that fungal community composition is a consideration when undertaking and designing any seagrass transplant or restoration or programme. Work such as this adds to our understanding of the seagrass ecosystem in an area of the world that is the global epicenter of seagrass diversity, yet is still one of the most understudied from a seagrass perspective.