Analysis of Cabernet Sauvignon and Aglianico winegrape (V. vinifera L.) responses to different pedo-climatic environments in southern Italy

Water deficit is one of the most important effects of climate change able to affect agricultural sectors. In general, it determines a reduction in biomass production, and for some plants, as in the case of grapevine, it can endorse fruit quality. The monitoring and management of plant water stress in the vineyard is critical as well as the knowledge of how each specific cultivars react to it. A multidisciplinary study was carried out to compare the Cabernet Sauvignon and Aglianico grapevine responses to different pedoclimatic conditions of southern Italy, in three areas devoted to high-quality wine production of Campania, Molise, and Sicilia regions. This study reports the preliminary results of the Italian National project “Influence of agro-climatic conditions on the microbiome and genetic expression of grapevines for the production of red wines: a multidisciplinary approach (ADAPT)”. In each site, the environmental characteristics were described and the soils characterized through a pedological survey. During 2020-2021, soil water content and the principal weather variables (e.g., temperature, rainfall, solar radiation, etc.) have been monitored by means of in situ stations, while plant responses collected by means of field campaigns (LAI, LWP, grapes composition). The agro-hydrological model SWAP was used to solve the soil water balance in each site and to determine the Crop Water Stress Index (CWSI) from April to October in the years 2020 and 2021. The obtained CWSI index was compared with data collected on plant status (e.g., LWP) and correlated to grapes quality (e.g., sugar content, acidity) in each site. Finally, the potential CWSI of each experimental site was determined on reference and future IPCC climate scenarios RCP 4.5 and RCP 8.5 to classify the attitude to produce plant water stress of each site and the expected future evolution.