Effect of alternative fungicides and inoculation strategy on yeast biodiversity and dynamics from the vineyard to the winery

Fungi and oomycetes found in vineyards cause diseases such as powdery and downy mildew. Consequently,conventional and alternative agronomical practices are widely used prior to harvest to protect grapes. Alternativeproducts are considered more eco-friendly and environmentally sustainable in comparison to conventionalchemical products. However, the effect of these alternative products on yeast ecology, from the vineyard to thewinery, is poorly understood. This study compared the effect of alternative and conventional chemical antifungalcompounds (copper and sulphur based) on grapes' mycobiota in the vineyard and during subsequent wineryfermentation using culture-dependent and -independent approaches. Culture-dependent data indicated atreatment-dependent effect on the load and diversity of yeast populations on grapes. It was found that thepopulation of Hanseniaspora uvarum was higher on grapes previously treated with laminarin and copper,compared to the other levels registered on grapes previously treated with the rest of antifungal products tested inthis study (including the untreated and conventional treatment controls). Concerning, wine quality, the chemicalcomposition was not correlated to the application of antifungal treatment in the vineyard. Understanding theeffect of different antifungal products on grape and wine microbial communities may help in setting upguidelines for wine grape production. These guidelines, can be used to guarantee quality in the pursuit of asustainable competitive advantage in the market."