Diversity of arbuscular mycorrhizal fungi in restinga and dunes areas in Brazilian Northeast

Abstract

Strong anthropogenic pressure, mainly mineral extraction, is one of the main factors leading to degradation of the Brazilian coastal environment. Strategies to recover these areas include replanting native plant species, and symbiotic fungi from the neighboring area might be important for the establishment of the new vegetation. Species richness, diversity and community composition of arbuscular mycorrhizal fungi (AMF) were investigated in NE Brazil in two natural areas, ‘restinga’ forest and seaside ‘restinga’, and in two areas of revegetated dunes after mining activity 20 and 8 years ago. Soil samples were collected during the dry (March) and wet (September) seasons of 2009 in Mataraca, Paraiba State, Brazil. Based on glomerospore morphology, 34 species of AMF were recorded, of which 29 were identified in field samples and five after trap culturing, with the greatest diversity and richness found in the dune revegetated 8 years ago. The sampling effort allowed an assessment of between 70 and 80 % of the species estimated for the areas by the first-order Jackknife index. Among the generalist species Gigaspora margarita was the only one found in all areas and during both collection periods. The similarity of AMF species between the revegetated areas and the seaside ‘restinga’ was >60 %, supporting the hypothesis that this area represents a source of propagules, but the substrate used for seedling production may also bring other species, enabling the recovery of the AMF community in the mined and revegetated dunes.