Beyond conventional: controlled-release fertilizers maintain yield, quality, and soil health with reduced environmental footprint

Optimizing nitrogen (N) management in viticulture is crucial for sustainable grape production, particularly amidst escalating environmental concerns and climate change. This study investigated the efficacy of a Controlled-Release Nitrogen (CRN) fertilizer as a sustainable alternative to conventional mineral NPK fertilization in grapevine, applying CRN at a total dose reduced by 25% compared to the conventional NPK treatment. We comprehensively evaluated vine agronomical responses (N status, yield, grape quality), alongside environmental impacts on water resources, soil properties, and microbial communities over multiple years. Results consistently showed that CRN maintained superior vine N status, as indicated by higher SPAD values, suggesting more consistent N availability throughout the season and improved plant resilience. Crucially, despite the reduced application dosage, CRN achieved grape yields and must quality parameters (e.g., TSS, pH, acidity, YAN) comparable to the conventional NPK treatment. Furthermore, the volatile aroma profile of the grapes remained unaffected by the CRN application. Environmentally, CRN reduced nitrate leaching, decreasing nitrate concentration in water, and sustained the metabolic activity and functional diversity of soil microbes. These findings underscore CRN as a valid solution for sustainable viticulture, offering comparable productivity and quality with reduced environmental footprint and enhanced ecosystem resilience to climate change challenges.