Soil mycobiome under different land uses in the southern Amazon: a metataxonomic approach
agriculture, fungal diversity, Glomeromycota, ITS2/D2-LSU, next-generation sequencing (NGS).
Fungi represent a highly diverse and widely distributed taxonomic group, playing essential roles in ecosystems. Understanding fungal community structure across different land-use systems is crucial for elucidating their roles in environmental dynamics and their contributions to sectors such as agriculture. Although the Amazon harbors a rich diversity of plant species that support a wide diversity of soil fungi, it remains the least-studied Brazilian biome in terms of fungal diversity. In this study, we collected soil samples from a native forest area within Cristalino State Park, Mato Grosso, and from an adjacent area recently converted into an agricultural system. Our goal was to characterize fungal communities and ecological guilds using high-throughput sequencing (NGS), with a parallel focus on the identification of arbuscular mycorrhizal fungi (AMF). The ITS2 region was used to characterize general fungal communities, while the D2-LSU region targeted AMF assemblages, combined by morphological analysis of spores. A total of 4,191 OTUs belonging to eight phyla and 130 genera were identified, with Ascomycota and Fusarium predominating, in addition to 64 AMF OTUs from the LSU libraries, including potentially novel taxa, and 41 morphospecies. Although alpha diversity of the general fungal communities did not differ between areas, beta diversity differed markedly and was primarily influenced by soil pH, also reflecting functional reorganization between agricultural and forest soils. For AMF, both alpha and beta diversity varied between systems, with higher richness in agricultural soils mainly associated with increased pH. These results demonstrate that Amazonian soils harbor high fungal richness, including potential new species, and that land-use change promotes taxonomic and functional restructuring of soil communities.