Diversity of arbuscular mycorrhizal fungi (Glomeromycota) in adjacent areas of different land use in Nepal

Disturbances can affect the incidence of Arbuscular Mycorrhizal Fungi (AMF) in both agricultural and natural ecosystems. The present study is a first attempt for the qualitative assessment of AMF diversity in adjacent areas of a forest ecosystem with different land uses and assess levels of mycorrhizal colonization by these fungi. A total of five soil samples were taken randomly from each of the following areas situated within the same landscape: undisturbed coniferous forest (UF), degraded forest (DF) and cultivated land (CL). A total of 22 taxa of arbuscular mycorrhizal fungi belonging to eight genera were identified morphologically, Glomus and Acaulospora being the most common. Species richness ranged from 11-14 among land use areas, with 14 species in UF and 11 species in CL. Acaulospora mellea, Gigaspora sp. and two non-identified Glomus species were detected in all areas. While species richness did not differ significantly amongst areas, diversity at the family level was 43% less in CL than in UF. Mean mycorrhizal colonization was higher in DF (28%) than CL (20%). We concluded that land use mainly affected fungal diversity only at the family level and had no impact on mycorrhizal development in sampled roots. This work provides the first step to identify native AMF species in Nepal that might be cultured for further use by small farmers in a sustainable agriculture approach.