Grant: Engage Grants Program

In white wines, the wine aroma plays a major role in determining wine quality and economic value. InGewürztraminer, the aroma makeup is built in the vineyard where key aromatics accumulate in the grapes.Irrigation strategies have been largely used as a tool to improve the composition of red grapes but very limitedinformation is available on the impact of these strategies on the accumulation of aromatics in Gewürztraminer.Andrew Peller Limited is one of the largest wineries in Canada and owns vineyards in both British Columbiaand Ontario. In Okanagan Valley BC, vineyards require frequent irrigation since limited rainfall during thegrowing season is not sufficient to sustain optimal grape production at a large-scale. In Okanagan Valley,Andrew Peller Limited owns about 40 acres of Gewürztraminer that are normally irrigated to sustain theproduction. Terpene compounds characterize the aroma of Gewürztraminer wine. Recent studies indicate thatsevere water deficit can promote the accumulation of terpenes - key wine aromatics - in grapes. However, thesestudies have indicated that not all the varieties respond in the same way and that the timing of the deficitapplication is critical for promoting the terpene production.Dr. Castellarin and Andrew Peller Limited will implement four irrigation regimes in a Gewürztraminervineyard. Andrew Peller Limited will establish the irrigation treatments in the vineyard accordingly to arandomized block design. Dr. Castellarin's group will perform physiological measurements in the vineyard(leaf water potential and leaf gas exchanges) and metabolite analyses in the laboratory (total sugars, titratableacidity, abscisic acid, and terpenes).This project aims to evaluate the effect of deficit irrigation strategies on the concentration of terpenes inGewürztraminer. The goal of the project is to identify the irrigation strategy that maximizes the level ofterpenes in this variety. This information will benefit the BC grape and wine industry that might adopt newstrategies for improving grape and wine quality in the vineyard and reducing the irrigation water usage.