Assessing the grapevine crop water stress indicator over the flowering-veraison phase and the potential yield lose rate in important European wine regions

In Europe, most of vineyards are managed under rainfed conditions, where water deficit has become increasingly an issue. The flowering-veraison phenophase represents important period for vine response to stress, which is known depend on variety characteristics, soil and climate conditions. this paper, we have carried out a retrospective analysis European wine regions over 1986–2015, with objectives assess the mean Crop Water Stress Indicator (CWSI) during phase, potential Yield Lose Rate (YLR) due seasonal cumulative stress. Moreover, also investigate if advanced phase can lead alleviated CWSI recent-past thus contributing reduced YLR. A process-based grapevine model employed, been extensively calibrated simulating both flowering veraison stages using location-specific observations representing 10 different varieties. Subsequently, grid-based modelling implemented gridded datasets phenology parameters. findings suggest higher tend However, contrasting patterns found between in France-Germany-Luxembourg Italy-Portugal-Spain. former tends slight-to-moderate drought conditions (CWSI<0.5) along negligible-to-moderate YLR (<30%), whereas latter severe-to-extreme (CWSI>0.5) substantial (>40%). Wine prone high risk (CWSI>0.75) identified, concentrated southern Mediterranean Europe. Advanced could benefited from more spring precipitation cooler temperatures Italy-Portugal-Spain, leading For those France-Germany-Luxembourg, precipitation, but prevalent reductions found, possibly shifted towards growing-season evaporative demands. Our study demonstrates flowering-verasion critical yield, impacts Central Southern regions. This be warmer climate, having implications vineyards. overall outcome may provide new insights appropriate viticultural management deficits change.