Effets de l’application d’acide gibbérellique (GA3) sur la qualité de raisins et de vins produits en climat tropical au Nord-Est du Brésil

Pomace, stem, grapevine leaves, and vine shoots arise as so called winery by-products during the wine production process.

The elaboration of sparkling wine is a demanding process requiring technical as well as scientific skills. Uncovering the role of the terroir to the final product quality is of great importance for the wine market. Although the impact of the yeast strains and their metabolites on the final product quality is well documented, the action of bacteria still remains unknown. The malolactic fermentation (MLF) is carried out by the lactic acid bacteria after the alcoholic fermentation in order to ensure the microbial stability during the second fermentation that takes place in the bottle or in tanks. Oenococcus oeni is the only selected species to drive MLF that has been commercialized for sparkling wine elaboration and it is naturally present on grapes, in the cellar and also in the final product. However, whether the bacterial strain contributes to the sensory characteristics of sparkling wine is still questioned.

Micropropagation is an important alternative to conventional methods of plant propagation. The objective of this study was to optimize a protocol for in vitro micropropagation of selected grapevine hybrids (H19 and H20) that are included in our breeding program. For the sprouting initiation experiment, nodal cuttings with only one axillary bud from two hybrids were separated, disinfected, and cultivated in 50% Murashige Skoog nutrient medium (½ MS) and Woody Plant Medium (WPM), adding 4.4 µM benzyladenine (BA) in both mediums.

In recent years, Mediterranean regions are being affected by marked climate changes, primarily characterized by reduced precipitation, greater concurrence of temperature extremes and drought during the growing season, and increased inter-annual variability in temperatures and rainfall. Generally, high-quality red wines need moderate water deficit. Hence, irrigation may be needed to avoid severe vine water stress occurring in some vintages and soils with low holding capacity. The aim of this work was to evaluate the effects of soil recharge irrigation in pre-sprouting and summer irrigation every week (30 % ETO) from the pea size state until the end of ripening (RP) compared to exclusively summer irrigation every week (R) in the same way that RP, on must volatile composition at harvest.

The conceptual image of a wine related to the terroir has consequences in technical terms. Among factors affecting the typicality, producers put forward the environmental factors of the terroir system