High-resolution aerial thermography for water stress estimation in grapevines

Berry shriveling (BS) in vineyards are caused by numerous factors such as sunburn, dehydration, stem necrosis. Climate change results in an increase in day and night temperatures, rainfall throughout the year, changes in the timing and quantities, long dry summers and a combination of climatic variability such as floods, droughts and heatwaves). Grape development and its composition at harvest is influenced by the latter as grape metabolites are sensitive to the environmental conditions. The grape berry experiences water loss and an increase in flavour development as a result of the BS. An increased sugar content in grapes will result in higher alcohol wines and concentration of grape aromas which may be detrimental to the final wine quality.

The protein haze formation in white and rosé wines during storage, shipping and commercialization has always been an important issue for winemakers. Among the various solutions industrially proposed, the use of bentonite is certainly the most widespread. However, the harmful effects of this treatment are known either in terms of wine volume loss and wine flavour and aroma.

A part, at least, of the fruity aroma of red wines is the consequence of perceptive interactions between various aromatic compounds, particularly ethyl esters and acetates, which may contribute to the perception of fruity aromas, specifically thanks to synergistic effects.1,2 The question of the indirect impact of non-fruity compounds on this particular aromatic expression has not yet been widely investigated. Among these compounds higher alcohols (HA) represent the main group, from a quantitative standpoint, of volatiles in many alcoholic beverages. Moreover, some bibliographic data suggested their contribution to the aromatic complexity by either increasing or masking flavors of wine, depending of their concentrations.

Context and purpose of the study. The growing need for sustainable solutions in viticulture has led to increased interest in biostimulants that can enhance plant resilience to both abiotic and biotic stresses.

Un grand nombre d’études ont été consacrées à l’évaluation quantitative des effets de climat sur la qualité des vignes, dans différents contextes climatiques. Généralement, la vocation viticole d’un terroire peut être étudiée par des approches mono ou multidisciplinaires.