Estrutura da comunidade de fungos micorrízicos arbusculares em florestas de Araucaria angustifolia (Pinales: Araucariaceae)

Abstract

Araucaria angustifolia, native and with ecological and economic value, is listed as critically endangered. This species has an intrinsic symbiotic relationship with arbuscular mycorrhizal fungi (AMF), microorganisms responsible for the acquisition of essential nutrients and tolerance to abiotic stresses, however, the presence or absence of these AMF can be influenced by environmental variables of the local landscape. The objective of this study was to verify the behavior of the community structure of arbuscular mycorrhizal fungi (AMF) in A. angustifolia forests with different landscape characteristics using Bayesian modeling. AMF abundance was verified by counting spores, richness by morphological identification’ spores located in the rhizosphere and litter and analysis carried out by Bayesian inference and Monte Carlo simulation via Markov chains (MCMC). Richness reached the plateau of the species accumulation curve and changed with the predictive variables evaluated. Distance from the edge, soil phosphorus and herbaceous stratum cover were negatively correlated with soil and litter richness, while total vegetation cover and litter content were positively related to richness. Some taxa had variable behavior in relation to the predictive variables and Acaulospora mellea was more related to degraded environments. These findings suggest that local environmental variables influenced the assessed AMF diversity parameters