Terroir in Slovak viticulture area

«L’Observatoire Grenache» est un réseau de parcelles qui a été mis en place par l’Institut Rhodanien en Vallée du Rhône sur les millésimes de 1995 à 1999. Composé de 24 parcelles de Vitis vinifera L. cv Grenache noir, ce réseau vise à étudier l’influence du terroir (sol, climat et vigneron) sur la qualité des vins. Les parcelles ont été choisies afin de représenter différentes situations géographiques et géopédologiques de la vallée du Rhône. Le matériel végétal (clone, porte-greffe), la taille (cordon de Royat), la densité et l’âge de la parcelle ont été encadrées. Ainsi les conditions de milieu (sol, climat) et les pratiques du vigneron étaient les principales sources de variations.

Quercetin (Q), a phenolic compound released from grape skins during red wine maceration, has been identified as a source of instability in bottled wines, particularly Sangiovese, due to crystallisation. This phenomenon represents an economic challenge for producers and affects wine clarity and consumer perception.

Red grape pomace, a waste from wine production, can be valorised by extracting polyphenols, high-added value compounds used in cosmetics or oenology. For use at an industrial level, using green extraction techniques, pomace need to be stored before being processed. The aim of this study is to test various storage conditions in order to maintain high level of polyphenols over 180 days, while keeping storage cost economically interesting. In a first step, different storage conditions (ambient temperature or cooled (4°C) temperature, anaerobic (saturation with N2) or aerobic conditions, and addition of sulphur dioxide (SO2)) were compared on small samples (1 kg) packed in plastic pockets. The quality of storage was assessed by following the optical density of the pomace extract at 280 nm (DO 280 expressed as mg/l eq gallic acid), which is an indication of the amount of remaining extractable polyphenols.

Face à une concurrence de plus en plus rude entre pays producteurs, le vignoble de l’Anjou, déjà riche par sa diversité, souhaite renforcer sa logique de vins d’ A.O.C., notamment au travers de ses vins rouges.

Entomopathogenic nematodes (EPN) are well-known biological control agents combined with specific adjuvants that now allow their use against aerial pests. Lobesia botrana (Lepidoptera: Tortricidae) is one of the major harmful pests detected in worldwide vineyards. Previous studies demonstrated that the EPNs Steinernema feltiae and S. carpocapsae could control L. botrana. The hypothesis was that the best combination of EPN-adjuvant/timing (season/temperatures) will support the use of EPN in the vineyard against L. botrana with no impact on the grape performance.