Application of a citrus-derived biostimulant during grape ripening: effects in cell cultures and under field conditions

Abstract

Climate change is increasingly disrupting grape ripening, particularly by decoupling technological and phenolic maturity. This study assessed naringenin and naringin – abundant compounds in citrus peel – as stimulators of anthocyanin biosynthesis and evaluated a citrus-waste-derived biostimulant under field conditions. In grape cell cultures, 1.5 mM naringenin and naringin were applied separately and jointly. Anthocyanin content, callus viability and untargeted transcriptomic responses were evaluated. In the vineyard, treated and control Grenache and Tempranillo grapes were harvested when controls reached 21 °Brix. Grapes and resulting wines were analysed for classical oenological parameters and sensory characteristics. The flavonoids were not toxic to callus cultures, and their combined application increased anthocyanin content and modified gene expression. Under field conditions, however, the biostimulant did not increase anthocyanins or the total polyphenol index in grapes or wines, although it reduced wine ethanol content. While further research is required, citrus-derived biostimulants may offer a circular-economy strategy for addressing the imbalance between technological and phenolic maturity caused by global warming.

References

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2. Moro, L; Da Ros, A; Da Mota; R. V.; Purgatto, E.; Mattivi, F.; Arapitsas, P; (2020). LC–MS untargeted approach showed that methyl jasmonate application on Vitis labrusca L. grapes increases phenolics at subtropical Brazilian regions. Metabolomics, 16 (2).
3. Ontañón, I. Application of a Citrus-Derived Biostimulant during Grape Ripening: Effects in Cell Cultures and under Field Conditions. Recording of the presentation delivered at Enoforum Spain 2026, Zaragoza, 20–21 May 2026. Available soon on Infowine Premium: https://vinidea.it/es/brand/infowine/

Acknowledgements

Project EFA102/01 CLIMAROMA was 65% co-funded by the European Union through the Interreg VI-A Spain–France–Andorra Programme (POCTEFA 2021–2027), which aims to strengthen the economic and social integration of the cross-border area.