As part of the IRRIGAVIT project, researchers from the Agricultural Institute of Slovenia, in collaboration with the University of Udine, tested various irrigation protocols in three terraced experimental and demonstrative vineyards cultivating pinela, chardonnay, and merlot varieties in two Slovenian areas: Šmarje and Planina in the Vipava Valley and Neblo in Goriška Brda. The water status of the plants has been monitored from April 2024 and will continue until the end of the project in September 2025.
The calibration of the Decision Support System (DSS Vintel) for monitoring pre-dawn water potential (Ψpd) is being conducted in relation to different treatments (from fruit set to harvest: -0.50 MPa, from fruit set to harvest: -0.30 MPa).
Vine drought stress, measured with the assistance of colleagues from KGZS Nova Gorica and RRA Severne Primorske d.o.o. Nova Gorica using the Scholander pressure chamber, was compared with the DSS Vintel algorithm. The DSS Vintel receives climatic data from Weenat weather stations (three separate units for measuring temperature, air humidity, wind direction and speed, and solar radiation at each location).
In the last week of August, the pinela variety was harvested in the flysch terraces of Šmarje where we studied three vineyard scenarios through three theses with different irrigation regimes: Moderate water stress (73 liters of water per vine added), Medium-to-strong water stress (44 liters of water per vine added), and No water stress (164 liters of water per vine added). The zelen variety was harvested in Planina, while merlot was harvested in the vineyards in Goriška Brda.
The results will assist winemakers in planning and implementing irrigation with the aim of optimizing water use and improving grape and wine quality. The harvested grapes were weighed and brought to the Agricultural Institute of Slovenia for winemaking and analysis. Grape sampling also continued during the harvest period.