Towards a sustainable viticulture: The combination of deficit irrigation strategies and agroecological practices in Mediterranean vineyards. A review and update

In this study we review the state of the art of different physiologically-based water-saving irrigation strategies and methods used to improve productive water use efficiency (WUE_yield) and berry and wine quality in vineyards. We also show how these irrigation practices, combined with more sustainable soil management and other agroecological practices, can help to mitigate the negative effects of climate change on wine grapes cultivation and make irrigated Mediterranean vineyards more resilient and sustainable. We analyse the deficit irrigation (DI) strategies used most often for different varieties and edaphoclimatic conditions. We review the latest advances in the application of regulated deficit irrigation (RDI) and partial root zone drying irrigation (PRI) strategies in grapevines (red and white grapes), as well as other irrigation methods used less frequently in vineyards to improve WUE_yield, berry quality and irrigation efficiency, such as subsurface drip irrigation. We also analyze recent findings concerning the physiological response of the vine to water stress with more holistic approaches such as, hydraulic safety marging and stress distance, and discuss how to translate these physiological approaches into the practical application of RDI management in field conditions, according to the genotypic characteristics and degree of drought tolerance of the variety/rootstock combination. We review optimum vine water status ranges and the thresholds proposed for better deficit irrigation scheduling in vineyards. In addition, we consider sustainable soil management practices - such as cover crops, mulching, composting, reduced tillage, mutualistic plant-microorganisms interactions, and agroforestry - and their potential as beneficial agroecological practices to improve WUE, soil/vine performance, and other ecological services in RDI vineyards within a more sustainable farming system (organic farming). The idea is to design sustainable and climate-change-resilient agricultural systems (e.g. vineyards) in Mediterranean semi-arid areas.