Journal of the Science of Food and Agriculture, 2026 (SCI-Expanded, Scopus)
Background: Fullerenol (C60(OH)12–42), a water-soluble carbon-based fullerene derivative, is recognized for its stress-mitigating potential; however, systematic and comparable evidence regarding its dose- and application-dependent effects on plant growth and development remains limited. In this study, fullerenol was first characterized, and its antifungal activity against five phytopathogenic fungi was assessed. Subsequently, increasing fullerenol concentrations were administered to safflower plants through foliar spraying and root nutrient solutions, and physiological responses were evaluated after 7 days. Results: Fullerenol showed effective functionalization and solvent-dependent absorption properties, while zeta potential and dynamic light scattering analyses confirmed moderate colloidal stability. Strong, concentration-dependent antifungal activity was detected, particularly against Fusarium oxysporum and Sclerotinia sclerotiorum, highlighting its promise as a selective antifungal agent. High concentrations administered via nutrient solution markedly inhibited plant growth and relative water content, increased ion leakage, and reduced pigment levels, including carotenoids. These doses also slightly impaired photosystem II (PSII) structural and functional integrity and restricted electron transport, with high-dose foliar applications producing even stronger negative effects. In contrast, low-dose foliar treatments enhanced plant growth by increasing shoot length and significantly improved photosynthetic performance by strengthening exciton energy capture, oxygen-evolving complex activation, and electron transport. OJIP chlorophyll a fluorescence kinetics and JIP test parameters demonstrated that these benefits were most pronounced at 10 mg L−1 fullerenol. Conclusion: Overall, the results reveal that low-concentration foliar fullerenol application enhances photosynthetic efficiency and promotes plant development, supporting its potential as a biostimulant for agricultural use. © 2026 Society of Chemical Industry.