Composition and diversity of soil fungi in Dipterocarpaceae-dominated seasonal tropical forests in Thailand

Although fungi play essential roles for ecosystems and have variety of interactions with many other organisms, little is known about the spatial patterns of the diversity of tropical fungi, including mycorrhizal fungi which form symbiotic relationships with plant roots. We elucidated the composition and diversity of soil fungi of seasonal tropical forests in northeast Thailand, to explore the effects of forest types (dry deciduous vs. dry evergreen forests). Fungal community in 350 soil samples from 7 forest plots divided into 3 forest types (three dry deciduous forest plots [DDF], three dry evergreen forest plots [DEF] and one fire-protected dry deciduous forest plot [FPDDF]) were investigated by pyrosequencing. In total, 830 fungal operational taxonomic units (OTUs) were detected among 32,492 reads obtained from 289 soil samples. Soil fungi belonging to 511 (71.4%) of orders of Ascomycota and 234 (21.5%) of orders of Basidiomycota, were detected. Although species richness of soil fungi did not significantly varied among the forest plots, the number of tree species was higher in FPDDF than in DEF, and DDF. The community structure of soil fungi was differentiated among the three forest types examined.