|dc.description.abstract||The effects induced by climatic changes have become more and more evident in wine regions located in mountain areas during the last years. The trend toward an increasing warming of the temperature is determining new ripening dynamics of grape berries that often lead to excessive sugar accumulation in fruits and alcohol development in wines. This fact somehow conflicts with the actual trend of wine markets that is increasingly asking for fresh, easy-to-drink, low alcohol wines. Moreover, other important quality traits of grapes and wines such as color, aroma, acidity and pH are detrimentally affected by ripening processes that occur largely during the hottest period of the season. Against this background, we aimed with this work to investigate the potentiality of different canopy management techniques to control and postpone the ripening process of Sauvignon blanc grapes.
Grapevine canopies were managed differently starting from the veraison phenological phase and, in detail, treatments were the follows: i) defoliation (partial leaves removal around the bunches); ii) antitraspirant application; iii) sprays with a photosynthesis inhibitor; iv) untreated control. The main biometric and physiological parameters were measured during the vegetative season, including the evolution of the berry quality traits in the period from veraison to harvest.
Results obtained at the end of the first year of the trial were interesting. Both the antitranspirant application and the defoliation approach were able to postpone by 5 to 10 days the achievement of the threshold fixed for the harvest (21.5 °Brix). Differently, the inhibition of the photosynthesis was of short duration and quickly recovered by the vines, leading to no significant effect on the ripening dynamic of grapes. As regarding to the final grape quality there were minor differences in the main traits, pH being the only parameter affected by the leaf pulling treatment (high pH average value). To conclude, first results of our trial show that a temporary and calibrated energy source limitation obtained throughout different canopy management approaches are able to slow down the ripening process and to postpone fruit harvest. More research is needed to test these methods under different seasonal conditions and to further clarify their implementation in the vineyard in terms of time of application, number of treatments and way of application,||en_US