Rising global air temperatures will lead to an increased evapotranspiration and altered precipitation pattern. In many regions this may result in a negative water balance during the vegetative cycle, which can augment the risk of drought and will require mitigation strategies. These strategies, ultimately, will mean the installation of irrigation systems in some winegrowing regions where vines were cultivated historically under rain-fed conditions and growers do not have many years of experience with vine water management.This review aims to provide a state-of-the-art summary of the recent and most important literature on vine water assessment for monitoring and adapting vineyard management strategies to production goals in view of global warming. Plant, soil and atmospheric methods are reviewed, and their advantages and drawbacks are discussed. Recent advances in plant water status measurement reveal the limitation of traditional techniques such as water potential, particularly in the context of drought and high vapor pressure deficit and the discoveries regarding hydraulic and stomatal regulation. New technologies can integrate heterogeneous sources of information collected in the vineyard at different spatial and temporal resolutions. Such new approaches offer new synergies to overcome limitations inherent to plant water status measurement techniques obtained directly or indirectly from proxy measurements.

The increasing risk of water deficit stress due to global warming subjects winegrowers of traditional rain fed viticulture regions to new challenges regarding vine water status assessment and possible drought mitigation strategies, such as irrigation.This review summarizes the most recent studies on the impact of water deficit stress on vine and berry physiology; it discusses the latest scientific advances regarding hormonal and hydraulic regulation and segmentation and addresses the current debate on iso/an-isohydricity within vine cultivars. Latest literature on irrigation frequency, water stress memory and the impact of abiotic factors such as VPD (Vapor Pressure Deficit), radiation, temperature and canopy architecture on vine physiology and water use, raise important questions on water status assessment and the implementation of irrigation strategies. Practical consequences regarding the effects of vine water regime on vine water regulatory mechanisms are discussed. Recent technical and scientific advances shed new light on how site specific irrigation strategies matching production objectives could improve vineyard water use.

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Airborne multispectral image data were compared with intercepted photosynthetic photon flux (PPF) in commercial winegrape (Vitis vinifera) vineyards of Napa Valley, Calif. An empirically based calibration was applied to transform raw image pixel values to surface reflectance. Reflectance data from the red and near-infrared spectral regions were combined into a normalized difference vegetation index. Strong linear response was observed between the vegetation index and PPF interception ranging from 0.15 to 0.50. Study results suggest the possibility of using optical remote sensing to monitor and map vineyard shaded area, thus providing spatially explicit input to water budget models that invoke evapotranspiration crop coefficient based calculations.

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