Phylogenetic diversity of endophyte assemblages associated with the tropical seagrass Enhalus acoroides in Thailand

Seagrasses are flowering plants inhabiting coastal and marine environments, with a worldwide distribution. They serve as feeding, breeding and nursery grounds for economically important marine organisms including endangered species. The tropical seagrass Enhalus acoroides was collected from Had Khanom-Mu Ko Thale Tai National Park, southern Thailand. The objectives of this study were to investigate for the presence of endophyte assemblages in E. acoroides , as well as to describe the diversity of endophytes based on LSU, ITS1, 2, 5.8S rDNA sequence analyses. Forty-two fungal assemblages were isolated and identified through molecular data. This resulted in a diversity of fungal groups of Ascomycota (98%) and Basidiomycota (2%). Three major Ascomycota classes including the Sordariomycetes (36%), Eurotiomycetes (33%) and Dothideomycetes (24%) were determined. The predominant ascomycete orders were the Hypocreales, followed by the Eurotiales and the Capnodiales , respectively. Additionally one taxon belonged to the Russulales , Basidiomycota and was possibly mycorrhiza. This study confirms that E. acoroides harbors a wide diversity of fungal endophytes, and provides a baseline for further studies on fungal-host plant interactions.