Postharvest ozone treatment in grapevine white cultivars: Effects on grape volatile composition

Varietal Riesling aroma relies strongly on the formation and liberation of bound aroma compounds. Floral monoterpenes, green C6-alcohols, fruity C13-norisoprenoids and spicy volatile phenols are predominantly bound to disaccharides, which are produced and stored in the grape berry during berry maturation.

Erysiphe necator Schwein is a fungus that causes grapevine powdery mildew. It is one of the most problematic pathogens attacking Vitis vinifera L. The pathogen infects all green parts of the plant and reduces grape yield and quality. The suppression on mildew-susceptible cultivars requires intensive use of fungicides against pathogen, which has negative impact on the environment and human health.

The characterization of « the soil effect » in vine growing is often limited to the description of the physical components of the terroir. Many works were done in this direction and corresponded to geological, pedological or agronomical approaches. However, if the physical environment influences the vine and its grapes, its effect becomes limited at the scale of exploitation. Thus, it could be important to consider how the viticulturist « translated » the potential.

The Valpolicella area (Veneto Region, Italy) is famous for its high quality wines: Amarone and Recioto, both obtained from partial post-harvest dehydrated red grapes. The main cultivars used for these wines are Corvina and Corvinone. In this Region hundreds of years ago a particular training system (Pergola, cordon/cane with horizontal shoot-positioning) was developed. In the last 20 years the Guyot have been introduced in the area; now Pergola and Guyot are equally widespread in the Valpolicella area. In two different environmental conditions (hill and floodplain) two vineyards, one for each type of training system, were studied along two years (2011-2012).

Un travail sur les A.O.C. du piémont pyrénéen occidental permet de construire une hiérarchie de paramètres climatiques, géo-pédologiques, morphologiques, de saisir leurs niveaux d’interaction et d’élaborer une méthodologie pour proposer un zonage