Saccharomyces cerevisiae biodiversity in vineyards and its relationship with effluents and residues management in winery

DIAZ QUIROZ C.; FALCONI P.; STURM M.E.; COMBINA M.; MERCADO, L.

Mendoza

Congreso; 37° Congreso Mundial de la Vid y el Vino; 2014

Organizacion Internacional de la Vid y el Vino (OIV)

The ?Zona Alta del Río Mendoza? (ZARM) region constitutes the main viticulture region of Argentina where Malbec grapes, the emblematic variety of Argentinean winemaking, are cultivated. Previous studies in vineyards of this region have demonstrated the presence of different, and polymorphic, Saccharomyces cerevisiae populations. The close genetic relationship among these populations, with important differences related to their participation in wine production at cellar, was observed. Moreover, the impact on S.cerevisiae biodiversity of the distance from winery was demonstrated. The objective of the present work was to evaluate the biodiversity of S.cerevisiae in ZARM vineyards located a different distance from winery and with different irrigation strategies. Two Cabernet sauvignon vineyards belonging to the same winery and located in Agrelo, Luján de Cuyo, were study. Vineyard G is located far from the winery (400 m) and has a pressurized dripping irrigation system; while vineyard AR, is located near the winery (100 m) and irrigated with treated reused water. Samples of grapes and soil from both plots were analyzed. Additionally, samples of water from the effluents treatment pond and organic residues (pomace) deposited outside the winery and near treatment ponds, were evaluated. Samples were processed by direct seeding over plates and by self-enrichment to allow developing of S.cerevisiae yeasts. Intraspecific molecular characterization was made by interdelta PCR. The analysis of commercial ADY (active dry yeasts) used in vinifications in this region were included with the aim of evaluate their dissemination in the vineyards. Finally, molecular patterns were evaluated by constructing dendrograms with the UPGMA method. According to the results obtained, the impact on yeasts vineyard populations by irrigation method and distance to winery was observed. S.cerevisiae yeast from soils of vineyard G, located far from winery, could not been isolated. On the other hand, higher diversity of S.cerevisiae strains was observed in grapes from vineyard AR, irrigated with treated effluents. Patterns corresponding to ADY were found in both vineyards grapes, this indicated that there is no direct relation among dissemination of commercial strains and irrigation with the residual water or distance from winery. Patterns of isolated from effluent and pomace were found in the AR vineyard, which indicated the importance of irrigation water in the dissemination of S.cerevisiae in vineyards. Since during winemaking process large water quantities are used, mainly to cleaning, large volumes of effluents are generated. Nowadays, the wine industry is devoted to minimize the negative impact over environment; a sustainable alternative is the utilization of treated winery effluents to vineyard irrigation. We have observed that this practice modify yeats populations in vineyards, but it would not have a negative impact over them.