Which potential for Near Infrared Spectroscopy to characterize rootstock effects on grapevines?

Ozone is a potent oxidizing compound that quickly decomposes into oxygen without residues. Previous works reported that ozone is not only a disinfectant that directly harms the pathogens of the vine but also activates systemic defense systems in the plant by activating oxidative stress. We assume these systemic defense mechanisms are essential to the vines’ resistance to downy and powdery mildew (Plasmopara viticola & Erysiphe necator, respectively). The goals of the research are to examine the effect of spraying with ozone water on the plant’s resistance against the mentioned pathogens as well as to characterize the metabolic profile of the plants treated with ozone as well as physiological characteristics in the vines such as the level of Photosynthesis and crop yield. Vines in the vineyard sprayed with ozone water at concentrations of 2 and 4 PPM weekly and biweekly, untreated control & conventional spray. Leaves were taken from vines 2,4,7,9 and 11 days after exposure to ozone and inoculated with the pathogens.

The aim of the present work was to investigate Sauternes wines aromas. The flavor profiles of two wines (vintages 2002 and 2003) were investigated. Key-odorants have been determined by AEDA applied to Amberlite XAD-2 resin extracts. Various complementary techniques were used to identify the compounds (pHMB extraction, chemical synthesis of non-commercial standards, co-injections on two capillary columns, odor description at the sniffing port, GC-MS and GC-PFPD).

– Several practices can be applied to vineyards in order to ensure good healthy for grapevines, adequate yield and fruit quality. Among them, the use of cover crops is a relevant option for soil management. It increases the organic matter, improves water infiltration, reduces risks of soil erosion and greenhouse gas emissions, in addition improving biodiversity in the vineyard.

Uruguay is known for the production of Tannat wines, which is a neutral variety from an aroma point of view, but capable of providing aromatic precursors that are of interest in the production of wines for ageing. The main aromatic precursors present are glycosidic compounds and carotenoids. The contribution of carotenoid degradation by-products such as norisoprenoids to wine aroma is fundamental, as they are associated with pleasant aroma descriptors and very low olfactory perception thresholds. Several factors have been shown to influence carotenoid concentrations in grapes, such as cultivar, climatic conditions, viticultural region, plant water status, exposure to sunlight and ripening stage.

Over the past two decades, climate change has contributed to an increase in sugar content in grape must, and consequently, in the ethanol levels of wines.