Enhancing sweet cherry quality: magnesium and potassium applications increase bioactive compounds and antioxidant activity.

BACKGROUND

Sweet cherry is highly valued around the world for its sensory qualities. Bioactive properties play significant roles in sweet cherry quality and consumer acceptance due to its health benefits. Plant nutrition through balanced fertilizer application helps in abiotic stresses mitigation, enhancing the biosynthesis of bioactive substances. For three consecutive years, magnesium (Mg) and potassium (K) were applied as foliar sprays to sweet cherry trees of the Burlat cultivar, with the aim to improve phytochemical composition. Fruits from each treatment were harvested at the commercial ripening stage to evaluate cherry bioactive composition and antioxidant activity.

RESULTS

Overall, the phytochemical composition and antioxidant activity increased over the three trial years, reaching their highest values in 2021, highlighting the effects of continuous fertilization with Mg and K. The Mg treatments (especially Mg250 in 2019 and Mg125 in 2020) enhanced the phytochemical composition of sweet cherries by increasing total phenolics, flavonoids, ortho-diphenols, and anthocyanin contents, as well as boosting antioxidant activity. In contrast, K treatments (mainly K50) led to a decrease in all bioactive compounds and antioxidant activity. The levels of individual phenolic compounds varied across treatments; however, catechin, epicatechin, chlorogenic acid, and quercetin-3-O-rutinoside contents declined over the 3 years, while neochlorogenic acid and cyanidin-3-O-rutinoside levels increased, stabilizing in 2020 and 2021.

CONCLUSIONS

These findings offer valuable insights for enhancing sweet cherry bioactive properties. © 2025 Society of Chemical Industry.