From genes to vineyards: system biology and new breeding technologies for water stress tolerance in grapevines

 The manipulation of the genetic basis controlling grapevine adaptation and phenotypic plasticity can be performed either by classical genetics or biotechnologies.

Phenolic compounds are secondary metabolites of grapes. Plants produce a wide variety of this type of metabolites through diverse biosynthesis pathways and their production is sometimes a response to external stimuli, either environmental or biotic stresses. Some of them may act as chemical defenses against pathogens or herbivores and their synthesis is increased when the attack exists. However, it is remarkable that the synthesis of these interesting compounds can be activated even when the stimulus is not present, with the use of elicitors. These are substances that when applied exogenously trigger the biosynthetic pathways conducting to the synthesis of these defense compounds.

Aerial thermography has emerged as a promising tool for water stress detection in grapevines, but there are still challenges associated with this technology, particularly concerning the methodology employed to extract reliable canopy temperature values. This consideration is relevant especially in vertically trained vineyards, due to the presence of multiple surfaces which are captured by drone thermal cameras with high-resolution. To test the technology and the data analysis required, a field study was conducted during the 2022-2023 season in a model vineyard with multiple scions-rootstock combinations trained on a vertical shoot-positioning (VSP) system. Additionally, three irrigation regimes were implemented to introduce variability in water stress levels.

In 2008 the anthocyanin, flavonol and hydroxycinnamate (HCT) contents of the skins of five coloured berry cultivars (‘Escursac’, ‘Esperó de Gall’, ‘Galmeter’, ‘Valent negre’ and ‘Vinater negre’), of two white cultivars (‘Argamussa’ and ‘Prensal blanc’) and of one weakly rose cultivar (‘Giró ros’), native from Balearic Islands, were characterized.

The wine industry works to minimize pesticides and adapt to climate change. Breeding programs have developed disease-resistant grape varieties, particularly against downy and powdery mildew, to minimize pesticide applications [1]. However, their enological potential remains underexplored.