Radiation-associated effects on regulated deficit irrigation management in grapevine cv. Cabernet Sauvignon

The winegrowing sector consumes a lot of pesticides. Changes in vineyard are necessary in order to reduce or even stop using pesticides, and thus limit their harmful impacts on health and on environment. To answer these issues, the VITAE project (2021-2026) aims at designing pesticide free grapevine systems in France. For that, we take an interest in the vineyards using solutions to strongly reduce chemicals but also biopesticides. We assume that such vineyards exist and that they are implementing solutions that could inspire the design of free- pesticide system.

(-)-Rotundone, an oxygenated sesquiterpene, is a potent odorant molecule with a characteristic spicy aroma existing in various plants including grapes1. It is considered as a significant compound notably in wines and grapes because of its low sensory threshold (16 ng L-1 in red wine, 8 ng L-1 in water) and aroma properties. (-)-Rotundone was first identified in red wine made from the grape cultivar Syrah (regionally called Shiraz) in Australia1, and then it was found in several grape varieties such as Duras, Grüner Veltliner, Schioppettino and Vespolina from Europe2, 3. Several environmental factors affecting the accumulation of (-)-Rotundone during the grape maturation, were reported such as ambient temperature4, soil properties and topography5, soil moisture from irrigation and light exposure in the bunch zone by leaf removal2.

Falanghina, a typical wine from the Sannio (Campania region, Italy), hosts a complex fungal microbiota that significantly influences both fermentation dynamics and sensory characteristics.

Enzymatic browning (BE) of must is caused by polyphenol oxidases (PPOs), tyrosinase and laccase. Both PPOs can oxidize diphenols such as hydroxycinnamic acids (HA) to quinones, which can later polymerize to form melanins [1], which are responsible of BE in white wines and of oxidasic haze in red wines. SO₂ is the main tool used to protect must from BE thanks to its capacity to inhibit PPOs [2]. However, the current trend in winemaking is to reduce and even eliminate this unfriendly additive. Among the different possible alternatives for protecting must against BE, the inoculation with a selected Metschnikowia pulcherrima MP1 is without any doubt one of the most promising ones.

Gewürztraminer is a well-known wine famous for its aroma profile, which is characterized by rose petals, cloves, lychees, and other tropical fruit notes.