Partial rootzone drying (PRD): strategic irrigation management as viticultural tool affecting plant physiology and berry quality

Les paysages participent à l’identité des vins de l’Hérault, avec une grande richesse de diversité. Leur observation, au travers des quatre saisons, s’appuie sur deux dimensions primordiales : la genèse de leur construction par l’homme et l’esthétique. L’hiver est la saison la plus favorable au décryptage de ce vignoble étagé, du littoral méditerranéen aux premières pentes du Massif Central; il permet de lire l’histoire des stratégies viticoles des vignerons. Les autres saisons sensibilisent plus à la beauté de vignobles dans des écrins de végétation typiquement méditerranéenne. La multiplicité des pratiques culturales et des cépages contribue à cet attrait. L’incitation au parcours, en toute saison, est très forte grâce au réseau des routes et des chemins de vigne.

The brown marmorated stink bug (BMSB, Halyomorpha halys Stal) is an invasive pentatomid native to eastern Asia that is spreading rapidly worldwide, notably through human-mediated activities. Globally, it was reported in the USA, Canada, Italy, Hungary, and other European countries. BMSB has a broad host range that includes over 170 plants, many of agricultural importance, including various fruit, vegetables, row crops, and ornamentals. When present in the vineyard, the pest can affect yield and quality by directly feeding on berries resulting in fruit collapse and necrosis. Additional damage occurs when BMSB are carried into the winery within the grape clusters. The presence of BMSB during wine processing can affect juice and wine quality through the release of volatile compounds produced as a stress response. The major secretes compounds are tridecane and trans-2-decenal. Tridecane is an odorless compound and its effect on wine quality is currently unknown. Trans-2-decenal is an unsaturated aldehyde considered to be the main component of BMSB taint with strong green, coriander, and musty-like aromas. Its threshold value in wine was estimated at about 5 µg/L.

Wine is the result of a complex biochemical process. From a microbiological point of view, the grape berry is characterised by a heterogeneous microbiota composed of different microorganisms (yeasts, bacteria and filamentous fungi) which will play a predominant role in the quality of the final product. At this level, yeasts play a predominant role in the chemistry of wine, as they

Quantity and quality of flavonoïds in grape berries are important parts of their global quality. Several studies had shown that tannins are responsible for some major flavour properties of red wines such as colour, bitterness and astringency. Nevertheless, their synthesis and properties are still misunderstood. Some studies had suggested that the tannic pool was set before veraison. Thus, the comprehension of the relations between environment and setting of this tannic pool, up to the harvest, is not sufficient.

La délimitation et la caractérisation des zones viticoles posent en Espagne des problèmes spécifiques non seulement dus aux caractéristiques propres au territoire mais aussi à la dimension, la distribution et l’indice d’occupation viticole dans les appellations d’origine.