This influence of various rootstocks on the yield and grape composition of Sauvignon Blanc was examined. The yield on rootstock 41B/72 was 1 kg/vine or more higher than on rootstocks SO4 cl. 31, Riparia cl. 1 and Kober 5BB. The vines grafted on the Börner rootstock gave the highest weight of 100 berries (241 g). The highest seed weight of 100 berries (6.9 g) was found on rootstock 196/17 Cl, while the lowest one was on the Riparia cl. 1 (5.6 g). There was a strong, positive correlation (r = 0.91) between the berry and seed weights of vines on rootstock 41B/72 (2003). The total acidity content and the relationship between tartaric and malic acids were affected more by the weather conditions than by the rootstock. Relatively strong correlations between the grape yield and total soluble solids (r = -0.89), and between grape yield and total acidity (r = 0.76) were found in the grape juice on rootstock 41B/72 (in 2002).

In order to realize the goals of the EU Farm to Fork strategy, grape growers are introducing new grape-growing technologies. Among the new trends, “0-pesticide residue” protection is quite a promising one. Field trials were carried out in vineyards located in the Mediterranean part of Slovenia in 2021 and 2022 to test the “0-pesticide residue” (ZPR) grape protection system with the goal of producing wine without pesticide residues above the limit of 0.001 mg kg−1. The standard integrated grape protection program (IP) was compared to the ZPR program. The level of infection of leaves and grapes by fungal pathogens did not significantly increase due to the implementation of the ZPR spray program. The amount of yield and quality of yield were not decreased significantly, but a small financial loss of EUR 70–400 ha−1 appeared at ZPR grape production when compared to the IP production system. The ZPR system enabled a significant decrease in pesticide residue concentration in wine at a rate of 27 applied pesticide active substances in a rage from 20% to 99%. The goal of producing wine without pesticide residues above the limit concentration of 0.001 mg kg−1 was not completely achieved in these experiments, but we came very close to it with the tested spraying programs. Further finetuning of pesticide positioning and alternative plant protection products in 0-pesticide residue systems is needed.

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