Endophytic fungi of emersed halophytes in river deltas and tidal flats of the Korean Ramsar wetlands

This study aimed to obtain information on the diversity and distribution of the endophytic fungi in Ramsar wetlands. Vast salt marshes in Suncheon Bay, Korea, are formed by two types of ecotones (tidal flats and deltas) that are supported by the emersed halophytes Phragmites australis and Suaeda japonica. Overall, 324 endophytes were isolated from P. australis (six sampling points in the delta and five in the tidal flats) and S. japonica (six in tidal flats). Margalef’s, Menhinick’s, Shannon’s, and Simpson’s diversity indices significantly varied among the ecotones. In particular, higher variance in diversity value and unevenness was observed in the delta marsh compared with the tidal flat marsh. Further, morphological diversity in the delta salt marsh was 1.8 times higher than that of the tidal flat. Comprising several dominant genera (Aspergillus, Cladosporium, and Penicillium), Epicoccum, Paraconiothyrium, Septoriella, and Talaromyces were widely distributed regardless of the aquatic conditions or halophyte species. This study highlights the distinct distribution and diversity of marine endophytes in various ecotones that can physically protect the coastal areas. This data is of much value to secure a national culture collection for future restoration of the coastal wetlands and their ecosystems.