Hyperspectral imaging and machine learning for monitoring grapevine physiology

A gradual decline in vineyards has been observed over the past twenty years worldwide. This might be explained by the climate change, practices change or the increase of dieback diseases. To increase the longevity of vines, we studied the impact of different pruning strategies in four adult and four young vineyards located in France and Spain. In France, vineyards were planted with Cabernet franc on 3309C while Spanish trials were planted with Tempranillo grafted on 110R. Vegetative expression, yield, quality of berries and wood vessels conductivity were measured. The distribution of vegetative expression, yield and berry composition between primary and secondary vegetation were quantified. Finally, tomography was used to evaluate the implication of the treatments on sap flows.
First results show that i) the respectful pruning leads to an increase of 30 to 50% more secondary shoots than the aggressive pruning in France and between 15 and 20% in Spain, ii) there is no major effect on the yield over the first two years following the implementation of the new pruning practices, although the proportion of clusters from suckers is higher on the respectful pruning method. On young vines, the development of the trunk according to a respectful pruning leads to a loss of harvest 2 years after planting. This is due to the removal, on the future trunk, of the green suckers which carrying bunches. This operation carried out in spring rather than during winter pruning, would promote a better leaf / fruit balance when the plant comes into production, and could lead to better hydraulic conduction in the vessels of the trunk. Maintaining these trials for several years will provide more robust data to assess the impact of these practices on the vines over the long term.

Stable isotopes of carbon (δ¹³C) and nitrogen (δ¹⁵N) provide valuable integrative indicators of grapevine water status (Gaudillère et al., 2002; van Leeuwen et al., 2023) and nitrogen metabolism (Santesteban et al., 2015, (Santesteban et al., 2024).

Grapevine is subject to multiple stresses, either biotic or abiotic, frequently in combination. These stresses may negatively impact the health status of plants and reduce yields. For biotic stress, grapevine is affected by numerous pest and diseases such as downy and powdery mildews, grey mold, black rot, grapevine fanleaf virus and trunk diseases (namely GTDs). The interaction between grapevine and pathogens is relatively complex and linked to various pathogenicity factors including cell-wall-degrading enzymes (especially CAZymes) and phytotoxic secondary metabolites, growth regulators, effectors proteins, and fungal viruses.

La Franciacorta è una piccola regione collinare della provincia di Brescia. Il territorio è molto eterogeneo sia dal punto di vista geologico, che geomorfologico e pedologico. Circa 1.000 ettari sono destinati alla produzione di uve Chardonnay, Pinot bianco e Pinot nero per il vino Franciacorta ottenuto unicamente utilizzando la lunga fermentazione naturale in bottiglia.

The table grape export business in Argentina had its boom in the last 2000s, when in 2008 it reached a little more than US $ 88,000,000. Since that time, the volume exported has been systematically reduced, which reduced the cultivated area and / or modified its destiny to wine or raisin production.