Ecology of cultivable yeasts in pristine forests in North-Patagonia (Argentina) influenced by different environmental factors

M. CECILIA MESTRE; SONIA B. FONTENLA; CARLOS A. ROSA

CANADIAN JOURNAL OF MICROBIOLOGY

NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS

Lugar: Otawa; Año: 2014 p. 1 - 12

0008-4166

The environmental factors driving yeast occurrence and their community structure in soil are not clearly stated for forests. There are few studies dedicated to Southern Hemisphere soil yeasts populations and even fewer focused on temperate forests influence by volcanic activity. The present work aimed to study the ecology of soil yeasts communities from pristine forests influenced by different environmental factors (precipitation, physico-chemical properties of soil, tree species, soil region and season). The survey was performed in four North Patagonian forests, two dominated by Nothofagus pumilio and two by N.antarctica. Yeast communities were described with ecological indices and species accumulation curves, and their association with environmental characteristics was assessed using multivariate analysis. Each forest site showed a particular arrangement of species as a result of environmental characteristics such as dominant plant species, nutrient availability and climatic characteristics. Cryptococcus podzolicus was most frequently isolated in nutrient-rich soils; Trichosporon porosum dominated cold mountain forests with low nutrient and water availability in soil; capsulated yeasts such as Crytococcus phenolicus dominated forest sites with low precipitation. The present work suggests that environmental factors affecting yeast communities may not be the current soil characteristics, but the result of complex interactions of factors including natural disturbances like volcanic activity.