TY - JOUR T1 - Phenological Sensitivity of Cabernet Sauvignon to Water Stress: Vine Physiology and Berry Composition JF - American Journal of Enology and Viticulture JO - Am. J. Enol. Vitic. DO - 10.5344/ajev.2011.11003 SP - ajev.2011.11003 AU - Boris Basile AU - Jordi Marsal AU - Mercè Mata AU - Xavier Vallverdú AU - Joaquim Bellvert AU - Joan Girona Y1 - 2011/07/26 UR - http://www.ajevonline.org/content/early/2011/07/26/ajev.2011.11003.abstract N2 - Information is scant on the sensitivity of berry composition to early-season water stress and how this is compared to the effects of late-season stress. We aimed at quantifying the effects of water stress on berry growth and composition of Cabernet Sauvignon grapevine at the following phenological stages: anthesis to fruit set, fruit set to veraison, and veraison to harvest. We used potted vines to facilitate imposing water stress early in the season. Four irrigation levels (0%, 25%, 50%, and 100% of calculated crop evapotranspiration, ETc) were applied and midday leaf water potential and leaf gas exchange parameters measured. Berry composition was evaluated by measuring titratable acidity and concentrations of soluble solids, anthocyanins, and polyphenols. Water stress decreased net CO2 exchange rate and vine green leaf area. Berry composition significantly correlated with the vine water status but the nature of the relationship depended on the phenological stage and on the parameter measured. Berry composition (in terms of concentration of anthocyanins and polyphenols) was improved when: i) no water stress occurred from anthesis to fruit set (irrigation replacing 100% of ETc); ii) with mild water stress between fruit set and veraison (irrigation replacing 25% and 50% of ETc); and iii) with moderate to severe water stress in post-veraison (irrigation replacing 0% of ETc). ER -