Natural mycorrhizal association of two tropical N-fixing monospecific plantations Southeastern Brazil

Abstract

Forest association with arbuscular mycorrhizal fungi (AMF) can improve the uptake of nutrients and hence the growth of host plants and it exerts a crucial role in tropical nutrient-poor soils. Our work aimed to verify if there is natural mycorrhizal colonization in Plathymenia reticulata and Dalbergia nigra monospecific plantations. Soil sampling was collected in the vicinity of the trees and fine roots were selected. The fine roots were washed, clarified and then stained. The spore isolation and identification were assessed by the wet sieving and sucrose density centrifugation. Both P. reticulata and D. nigra roots have fungal structures (vesicles and hyphae). The species Glomus macrocarpum and Ambispora leptoticha were identified in the soil under P. reticulata and Glomus macrocarpum, Glomus agregatum, and Claroideoglomus etunicatum in the soil under D. nigra. Both species can naturally be associated with AMF and we can suggest that different fungi are colonizing the roots of each species.