Abiotic stress effects on grapevine (Vitis vinifera L.): Focus on abscisic acid-mediated consequences on secondary metabolism and berry quality.

This review deals with grapevine abscisic-acid (ABA) mediated responses to abiotic stress by addressing stress consequences mainly on berry quality. Accumulation of secondary metabolites as a plant defense strategy to abiotic stress is reviewed, together with perturbations of metabolite molecular pathways. The role of ABA is highlighted as a link between berry ripening process and grapevine response to stress. Abiotic stress (especially water scarcity, light and temperature) modifies growth and development of all plant organs. The response to abiotic stress at the berry level drives the accumulation in berry pulps, seeds and skins of secondary metabolites as a line of defense against cell damages. Viticultural practices can be managed to control stress plant response in order to influence berry secondary metabolite concentrations and profiles, reflecting on an enhancement of table grape and must quality and on their nutraceutical and health benefits, as grape berry secondary metabolites contribute to berry and wine taste and aroma, to the potential antioxidant capacity of fruit and wines, to wine stabilization and protection during ageing. Being stress response mainly ABA mediated, feeding of exogenous ABA to grapevine organs is reviewed as a tool to enhance grape quality and to control abiotic stress. Consequences in viticultural practices are discussed in relation to different abiotic stresses and global warming effects.