Elicitors application in two maturation stages of Vitis vinifera L. cv Monastrell: changes on the skin cell walls

Malolactic fermentation (MLF) is a desired process to decrease acidity in wine. This fermentation, carried out mostly by Oenococcus oeni, is sometimes challenging due to the wine stress factors affecting this lactic acid bacterium. Wine is a harsh environment for microbial survival due to the presence of ethanol and the low pH, and with limited nutrients that compromise O. oeni development. This may result in slow or stuck fermentations. After the alcoholic fermentation the nutrients that remain in the medium, mainly released by yeast, can be used in a beneficial way by O. oeni during MLF.

Wine-grapes in the Willamette Valley, Oregon, are grown on three major soil parent materials: volcanic, marine sediments, and loess/volcanic.

The northern vineyards produce wines with a high aromatic richness. The wines of Alsace are appreciated for the diversity of their aromas, the typicality of which was for a long time judged mainly according to the grape variety of origin. Alsatian winegrowers have however widely sensed the importance of the environment of the vine on the quality of the wines. Efforts are made to try to harmonize in a reasoned way the interaction between the natural environment and the plant material with a view to developing the character of the grape variety through the fine expression of the terroir and making the quality and typicality even more inimitable. wines produced in Alsace.

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 influence of two pre-veraison and post-veraison regulated deficit irrigation (RDI) strategies on yield and grape quality was analyzed during a two year period for mature grapevines (cv. Monastrell) in Southeastern of Spain