Genetic diversity of yeasts isolated from Eurasian populations of Vitis vinifera ssp Sylvestris (Gmelin) Hegi

Abstract

Vitis vinifera L. ssp. Sylvestris (Gmelin) Hegi is recognized as the dioecious parental generation of today’s cultivars. Climatic change and the arrival in Europe of pathogens and pests have led it to be included on the IUCN Red List of Threatened Species in 1997. At best of our knowledge, no studies on microbial populations of grape-berry surfaces have been done. The present work has been focused on the study of yeast occurrence and diversity on grape-berries collected from wild vines. Final outputs have allowed: i)to obtain precise information about yeast communities; ii) to provide an objective framework for the classification of the broadest range of species according to their extinction risk; iii) to select attractive yeast strains for their biotechnological potential, offering new opportunities to winemakers. Sampling plan was performed in Azerbaijan, Georgia, Italy, Romania and Spain. In all, 3180 yeast colonies were isolated and identified as belonging to 50 species, including Saccharomyces cerevisiae, by 26S rDNA D1/D2 domains and ITS region sequencing. Isolates of S. cerevisiae were also analysed by SSR-PCR obtaining 163 different genotypes. This study highlights the biodiversity potential of pristine environments that still represent a fascinating source to face common problems in winemaking.