Cumulative effects of repeated drought stress on berry composition, and phenolic profile: Field experiment insights

La brise de mer est un facteur climatique important pour le zonage viticole des régions viticoles côtières car l’accélération du vent qui lui est associée l’après midi ainsi que l’augmentation de l’humidité relative et la réduction de la température concomitantes sont significatives pour le fonctionnement de la vigne et, par conséquent, la qualité du raisin et du vin

Probably one of the most counterintuitive impacts of climate change on vine is the increased frequency of late frost. Champagne, due to its septentrional position is historically and regularly affected by this meteorological hazard. Champagne has therefore developed a strong experience in frost protection with first experiments dating from the end of 19th century. Frost protection can be divided in two parts: passive and active. Passive protection includes all the methods that do not seek to modify the vine’s environment or resistance at the time of frost. The most iconic passive protection in Champagne is the establishment of the individual reserve. This reserve allows to stock a certain quantity of clear wine during a surplus year to compensate a meteorological hazard like frost during the following years. Other common passive methods are the control of planting area (walls, bushes, topography), the choice of grape variety, late pruning, or the impact of grass cover and tillage. Active frost protection is also divided in two parts. Most of the existing techniques tend to modify vine’s environment. Most of the time they provide warmth (candles, heaters, windmills, heating cables…), or stabilise bud’s temperature above a lethal threshold (water sprinkling). The other way to actively fight is to enhance the resistance of buds to frost (elicitors). The Comité Champagne evaluates frost protection methods following three main axes: the efficiency, the profitability, and the environmental impact through a lifecycle assessment. This study will present the results on both passive and active protection following these three axes.

The introduction into the Italian wine supply chain of the latest generation of fungi-resistant grapevine varieties, endowed with a greater or lesser strong resistance to downy and powdery mildews, represents a valid tool of making viticulture more sustainable, particularly in northern regions of the peninsula, where climatic conditions accentuate the pressure of fungal diseases. However, the affirmation of resistant varieties is a function of their agronomic value, as well as of their oenological and sensorial value. The purpose of this study was to evaluate in detail the sensory potential of the new resistant varieties, in order to understand their real possibility of inclusion in the modern global enological context.

Field irrigation experiments were performed on young « Nonpareil » almond trees, mature « Bartlett » pear trees and mature « Pinot Noir » grapevines, to determine the relation of a number of alternative measures of plant water status (predawn and midday stem and leaf water potential), to a number of indices of plant physiological activity (leaf conductance, vegetative growth and fruit growth and composition).

The goal of this work was to determine the spatial variability of terroir using the isotope composition of wine. Carbon (δ13C) and oxygen (δ18O) stable isotope composition was measured in wines from Tempranillo (Vitis vinifera L.) vineyard, located in Rioja Appellation (Spain). Stable isotope composition, leaf area, vigour, yield components, grape and wine composition were determined in a grid of 85 geo-referenced points, that was drawn across the 5 ha vineyard area