Delaying irrigation initiation linearly reduces yield with little impact on maturity in Pinot noir

The ongoing climate change implies an increasing mean air temperature, which is signified by weather extremes or sudden changes between drought and local heavy rainfalls. These changing conditions are especially challenging for the established grapevine varieties growing under cool climate conditions due to an increased risk for fungal diseases like downy mildew (DM) and Botrytis bunch rot (BBR) as well as for grape sunburn. To meet that demand, the scope of most grapevine breeding programs is the selection of mildew fungus-resistant and climatic adapted grapevines with balanced, healthy yield and outstanding wine quality.

Sono stati presi in considerazione alcuni dati agrometeorologici dell’Oltrepò Pavese (temperature e piovosità degli ultimi 80 anni) e gli studi delle curve di maturazione condotti in zona sul Pinot nero da spumante negli anni (1988-1991, 1999-2000, 2006-2008), si nota che l’aumento progressivo negli anni delle temperature attive (indice di Winkler) ha determinato un anticipo dell’invaiatura, definita dal parametro “punto di incrocio” (intersezione delle funzioni di zuccheri ed acidità nel tempo), con conseguente anticipo della data di vendemmia di circa 12-15 gg.

This study aims to create an updated, agile viticultural climate index (similar to the Winkler Index) by performing in-depth analyses of current and historical data from industry partners in several major winegrowing regions. The Winkler Index was developed in the early twentieth century based on analysis of various grape-growing regions in California. The index uses heat accumulation (i.e. Growing Degree Days) throughout the growing season to determine which grape varieties are best suited to each region. As viticultural regions are increasingly subject to the complexity and uncertainty of a changing climate, a more rigorous, agile model is needed to aid grape growers in determining which cultivars to plant where. For the first phase of this study, 21 industry partners throughout Napa Valley shared historical phenology, harvest, viticultural practice, and weather data related to their Cabernet sauvignon vineyard blocks. To complement this data, berry samples were collected throughout the 2021 growing season from 50 vineyard blocks located throughout 16 American Viticultural Areas that were then analyzed for basic berry chemistry and phenolics. These blocks have been mapped using a Geographic Information System (GIS), enabling analysis of altitude, vineyard row orientation, slope, and remotely sensed climate data. Sampling sites were also chosen based on their proximity to a weather station. By analyzing historical data from industry partners and data specifically collected for this study, it is possible to identify key parameters for further analysis. Initial results indicate extreme variability at a high spatial resolution not currently accounted for in modern viticultural climate indices and suggest that viticultural practices play a major role. Using the structure of data collection and analyses developed for the first phase, this project will soon be expanded to other wine regions globally, while continuing data collection in Napa Valley.

The capture and valorization of fermentative CO2 have been developed for several years by the company w platform for internal uses, notably in the cellars: inerting, cooling, reduction of water consumption, extraction, with aroma valorization. In a context of climatic warming during the vegetative cycle, grapes are currently harvested with a significant sugar concentration, a phenomenon that is expected to intensify in the coming decades. The high alcohol content of the resulting wines goes against the demand of customers who are seeking high-quality wines with less alcohol.

The Mediterranean basin is one of the most vulnerable regions to Climate Change effects. According to unanimous forecasts, the vineyards of Castilla-La Mancha will be among the most adversely affected by rising temperatures and water scarcity during the vine’s vegetative period. One potential strategy to mitigate the negative impacts of these changes involves the identification of grapevine varieties with superior water use efficiency, while ensuring satisfactory yields and grape quality.