Unraveling the complexity of high-temperature tolerance by characterizing key players of heat stress response in grapevine

The main phenological stages (budburst, flowering, veraison, and ripeness) and the fruit composition of 34 Spanish minority varieties were studied to determine their cultivation potential and help winegrowers adapt their production systems to climate change conditions. In total, 4 control cultivars, and 30 minority varieties from central Spain were studied during a period of 3 campaigns, in the ampelographic collection “El Encín”, in Alcalá de Henares, Madrid. Agronomic and oenological characteristics such as yield, and total soluble solids concentration have been monitored.

Reducing sugar accumulation in grape (Vitis vinifera L.) berries may be a way to mitigate the effect of climate change. Managing canopy and crop load is an effective way to do so, however, reducing canopy size has been demonstrated to induce undesirable effects on anthocyanins. The aim of this study was to test if an application of exogenous ABA on the grape berries of defoliated vines (⅔ of the leaves removed) can result in slower sugar accumulation while maintaining grape and wine quality. An experiment with defoliation and exogenous ABA application on directly on clusters (factorial design 2×2) was performed with ‘Tempranillo’ fruit-bearing cuttings.

The utilization of non-Saccharomyces yeasts in the wine industry has increased significantly in recent years. Alternative species need commonly be employed in combination with Saccharomyces cerevisiae to avoid stuck fermentation, or microbial spoilage. The employment of more than one yeast starter can lead to interactions between different species with an impact on the outcome of wine fermentation. Previous studies[1] demonstrated that S. cerevisiae elicits transcriptional responses with both shared and species-specific features in co-culture with other yeast species.

Nitrogen (N) is quite important nutrient in grapevine development and must quality, but under Mediterranean climatic conditions, available soil water (ASW) during grapevine development can also influence vigour and must quality. The aim was to determine the influence of soil nitrate (NO3-) availability on N foliar, yield, and must quality in vineyards with similar available water holding capacity (AWC). For this purpose, four cv. Tempranillo (Vitis vinifera L.) vineyards were selected. All of them are placed in Uruñuela municipality (La Rioja, Spain), separated less than 2.5 km and in a slope <1 %, in soils with similar soil chemistry properties and with similar rooting depth (ranging between 105 cm and 110 cm).

Climate change will increase the frequency of water deficit situation in some European regions, by the increase of the evapotranspiration and the reduction of rainfalls during the growing cycle. This requires finding ways of adaptation, including the use of plant material which is more tolerant to drought. In addition to the varieties used as scions that result in the typicality of wines, rootstocks constitute a relevant way of adaptation to more stressful environmental conditions.