Occurrence and species richness of mycorrhizal fungi in soil under different land use

Abstract

This study aimed to assess the impact of different land uses on the spore density and richness of arbus- cular mycorrhizal fungi (AMF) in a Red Latosol of a tropical savanna biome in Brazil (“Cerrado”). Ten soil samples and roots were obtained from a riparian forest, a pasture, an annual crop production system with no tillage, and a coffee plantation in dry and wet seasons. Spores were extracted, counted, and identified from field soils, and roots were stained to assess mycorrhizal colonization. A total of 42 AMF species were detected in all four land uses. The genus Acaulospora had the largest number of species (18), followed by Glomus (6) and Gigaspora (5). Gigaspora decipiens and Gigaspora margarita were present in all areas, regardless of the sample period. Gigaspora decipiens was the species most frequently recovered and contributed to the majority of spores in coffee plantations and riparian forest. Cetraspora pellucida was dominant in the area of no tillage and Acaulospora tuberculata in the pasture. Low species richness was detected in soils under the coffee plantation, with AMF communities dominated almost exclusively by members of Gigasporaceae. We conclude that the area under the coffee plantation caused a reduction in the richness of AMF species and promoted a dominance of a single family AMF compared with the pasture area.