EFFECTS OF ZINC OXIDE NANOPARTICLES ON YIELD, NUTRACEUTICAL QUALITY, AND ANTIOXIDANT ACTIVITY IN JALAPEÑO PEPPER

Abstract

Nanotechnology has emerged as a promising tool in modern agriculture, particularly through the use of metallic nanoparticles with biostimulant and biofortifying properties. This field study evaluated the effects of foliar application of zinc oxide nanoparticles (ZnO-NPs) on jalapeño pepper (Capsicum annuum L.). Treatments consisted of five foliar concentrations (0, 50, 100, 150, and 200 mg L?¹), and the assessed variables included morphophysiological traits, yield components, biophysical fruit characteristics, nutraceutical quality, antioxidant activity, and zinc bioaccumulation. ZnO-NPs significantly enhanced yield-related traits, increasing total yield (48.34%), fruit length (13.91%), firmness (25.18%), and chlorophyll content (35.33%). Improvements in nutraceutical quality were also observed, including protein content (225%), flavonoids (82.19%), total phenols (118.41%), vitamin C (27.77%), capsaicin (80.21%), and total antioxidant capacity (12.12%). Catalase and peroxidase activities increased by 12.12% and 13.52%, respectively. Zinc concentration in the fruit increased by 55%, confirming a biofortifying effect. Overall, foliar application of ZnO-NPs modulated physiological, yield, and nutraceutical responses in jalapeño pepper plants. Concentrations between 100 and 150 mg L?¹ were identified as the optimal range for practical foliar application under field conditions.