Spores and Legumes: Building Edaphic Alliances in the Cerrado–Pantanal

Abstract

Arbuscular mycorrhizal fungi (AMF) are fundamental to the soil fertility of the Cerrado–Pantanal region, as they form symbiotic associations with plant roots, enhancing nutrient absorption and resistance to adverse conditions. The study evaluated six forage species (four legumes and two grasses) to identify the AMF community associated with their roots and rhizospheric soils.  The results showed that the family Acaulosporaceae was the most abundant (8.92 spores/g of soil), followed by Glomeraceae (5.46) and Gigasporaceae (2.92). The legumes exhibited greater diversity and affinity with the fungi: Stylosanthes showed a high association with Acaulosporaceae, while Arachis pintoi stood out for its strong relationship with Gigasporaceae. The grasses (Pennisetum purpureum cvs. Kurumi and Pioneiro) showed greater affinity with Glomeraceae. Acaulosporaceae presented the highest spore density, averaging 8.92 spores per gram of soil, significantly differing from the other families. This dominance indicates a higher adaptation to the edaphic conditions of the Cerrado–Pantanal, possibly reflecting a broader capacity to associate with diverse host species. Glomeraceae showed an intermediate mean (5.46 spores/g), while Gigasporaceae was the least abundant (2.92 spores/g), suggesting greater environmental sensitivity or a requirement for specific hosts.

It is concluded that legumes play an essential role in maintaining and enhancing AMF community diversity, forming edaphic alliances that increase nutrient availability and promote the sustainability of pastures in the Cerrado–Pantanal region.