Combination of NIR multispectral information acquired from a ground moving vehicle with AI methods to assess the vine water status in a Tempranillo (Vitis vinifera L.) commercial vineyard

Knowledge on the reflectance spectrum of soil is potentially useful since it carries information on soil chemical composition that can be used to the planning of agricultural practices. If compared with analytical methods such as conventional chemical analysis, reflectance measurement provides non-destructive, economic, near real-time data. This paper reports results from reflectance measurements performed by spectroradiometry on soils from two vineyards in south Brazil. The vineyards are close to each other, are on different geological formations, but were subjected to the same management. The objective was to detect spectral differences between the two areas, correlating these differences to variations in their chemical composition, to assess the technique’s potential to predict soil attributes from reflectance data.To that end, soil samples were collected from ten selected vine parcels. Chemical analysis yield data on concentration of twenty-one soil attributes, and spectroradiometry was performed on samples. Chemical differences significant to a 95% confidence level between the two studied areas were found for six soil attributes, and the average reflectance spectra were separated by this same level along most of the observed spectral domain. Correlations between soil reflectance and concentrations of soil attributes were looked for, and for ten soil traits it was possible to define wavelength domains were reflectance and concentrations are correlated to confidence levels from 95% to 99%. Partial Least Squares Regression (PLSR) analyses were performed comparing measured and predicted concentrations, and for fifteen out of 21 soil traits we found Pearson correlation coefficients r > 0.8. These preliminary results, which have to be validated, suggest that variations of concentration in the investigated soil attributes induce differences in reflectance that can be detected by spectroradiometry. Applications of these observations include the assessment of the chemical content of soils by spectroradiometry as a fast, low-cost alternative to chemical analytical methods.

The chemical composition of grape berries at harvest is one of the key aspects influencing wine quality and depends mainly on the ripeness level of grapes. Climate change affects this trait, unbalancing technological and phenolic ripeness, and this further raises the need for a fast determination of the grape maturity in order to quickly and efficiently determine the optimal time for harvesting. To this end, the characterization of variety-specific ripening curves and the development of new and rapid methods for determining grape ripeness are of key importance.

The sustainability and authenticity of grape juice production have gained increasing attention, particularly regarding the environmental impact and health benefits of organic practices.

[English version below]

On a étudié durant deux saisons de croissance (2002/2003 et 2003/2004) l’effet de l’orientation vertical des rameaux sur les paramètres physiologiques, végétatifs et reproductifs dans la région de Stellenbosch dans un vignoble du cépage Merlot sur 99 R conduite à espalier et taillé a cordon coursonné. Les vignes étaient espacées 2.7 x 1.5 m. L’irrigation a été appliquée quand la baie avait la dimension d’un pois et a la véraison.

Powdery mildew, caused by fungal pathogens, poses a significant threat to grapevines in the DOCa Rioja region. In efforts to improve control strategies while reducing reliance on conventional phytosanitary products, ozone could constitute a potential alternative. However, it has short persistence, thus requiring frequent treatments. This study aimed to assess the suitability of ozone as an active substance for controlling powdery mildew within a phytosanitary strategy aimed at reducing conventional phytosanitary product usage. The strategy integrating ozone with conventional products yielded powdery mildew levels comparable to conventional treatments in both disease incidence and severity.