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The main phenological stages (budburst, flowering, veraison, and ripeness) of 53 Spanish minority varieties were studied to determine their potential to help winegrowers adapt to climate change conditions. In total, 43 varieties were studied in the same location in Spain (Alcalá de Henares, in the Madrid region) and 10 varieties in 5 other regions (Galicia, Navarre, Catalonia, Extremadura, and Andalusia). Other traits of agronomic and oenological interest, such as yield and acidity, were also monitored. The results allow for the grouping of the varieties into several clusters according to the time of ripeness (very early—only for red varieties—and early, intermediate, and late, for both red and white varieties) and yield (high, medium, and low). The total acidity in the grape juice ranged from 3 to 11 g of tartaric acid/L. The average temperatures were higher (up to 3–4 °C during summer) compared to historical averages during the 1957–2021 time period. Advanced phenology phases and reduced acidity are regarded as negative effects of climate change for winegrowing practices. Since some minority varieties showed late or intermediate ripening, high acidity, and high (1 Kg/shoot) or medium (0.5 Kg/shoot) yield, our findings suggest that they may be cultivated in the coming years by winegrowers as an approach to mitigate climate change effects.

Wine phenolics are of considerable interest due to their implication in the organoleptic appreciation of wines and due to their bioactive functions as antioxidants. In this work, the effects of sustainable strategies in the vineyard, regulated deficit irrigation treatments (RDI) and crop load level (CL) on Tempranillo grape phenolics over two seasons was studied. Rainfed (T), early (EDI) and late (LDI) regulated deficit irrigation was applied. Cluster thinning (TH) and control (C) without cluster removal were also applied under each irrigation treatment. The effect of CL remained independent of RDI for all compounds, except for phenolic acids. The RDI influence on the grape skin phenolic profile was higher than CL in the dry season (2009); however, in 2010, the effect of CL was greater. In 2009, a tendency to increase anthocyanin and hydroxycinnamic acid content in grape skins was registered in EDI with respect to T. However, significant decreases in hydroxycinnamic and flavanol compounds were found in LDI. In 2010, the wettest year, CL increased all phenolic families’ content. Thus, it can be concluded that the effects of RDI and cluster thinning treatments depend on the family of compounds considered and the meteorological conditions of the year.

“Crop-forcing” is an effective technique to delay grape maturation to a period of lower temperatures, and in this way, improve grape quality. Because of the aggressiveness of this technique (removal of leaves and fruit to reinitiate a second vegetative cycle), it may affect the level of reserves and could provoke progressive vine exhaustion. The aim of the present work is to evaluate the short- and medium-term evolution of carbohydrate reserves in different plant organs and the effect of “crop-forcing” under different irrigation regimes on seasonal biomass production and its distribution. The study was carried out over a four years period (2017–2020), applying “crop-forcing” in three consecutive years (2017–2019) to the same vines on two different dates and using two irrigation strategies. The application of “crop-forcing” did not decrease root reserve levels in either the year of application or the following year, but did modify starch and soluble sugar levels in shoots and leaves in some moments of the vegetative cycle during the years of “crop-forcing” application. Total biomass production in terms of grams per vine was lower in the “crop-forcing” treatments and continued to be so when “crop-forcing” was no longer applied. The percentage of biomass in vegetative organs increased at the expense of productive organs.