Synthesis, Characterizations, and Field Evaluation of Chitosan‐Polyethylene Glycol‐Zinc Oxide Nanocomposite Coatings for Improved Wheat Germination and Yield

ABSTRACT This study aimed to synthesize nano‐enhanced chitosan‐polyethylene glycol (Cs‐PEG) coatings incorporated with zinc oxide nanoparticles (ZnO NPs) for the biofortification of wheat seeds, improving germination, growth, and zinc uptake. ZnO NPs and Cs‐PEG ZnO nanocomposites were synthesized and characterized using scanning electron microscopy (SEM), energy dispersive x‐ray spectroscopy (EDX), x‐ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), confirming their hexagonal wurtzite crystalline structure (41 nm crystallite size), elemental composition (Zn and O peaks, minor C from Cs‐PEG matrix), and functional group interactions within the Cs‐PEG matrix, respectively. Field trials compared control, Cs‐Blank, Cs‐PEG, and Cs‐PEG‐ZnO (1%, 3%, 5%) treatments. Results showed improved germination percentage (up to 100%), reduced mean germination time (3.2 days), and enhanced growth parameters including shoot length (18.5 cm), root length (15.5 cm), tillers per plant (5.1), spike length (8.9 cm), grain yield (16.3 g), and 1000‐grain weight (43.7 g) in Cs‐PEG‐ZnO 5%. In vitro zinc release over 14 days revealed concentration‐dependent behavior, with cumulative release of 7.1, 19.8, and 40.0 ppb for 1%, 3%, and 5% ZnO, respectively. The coatings demonstrated controlled zinc delivery, reduced leaching, and enhanced agronomic performance. This work highlights Cs‐PEG‐ZnO coatings as an effective strategy for seed biofortification, improving crop productivity while ensuring sustainable micronutrient management.