A titanium dioxide (TiO₂)-embedded sodium alginate–chitosan nanocomposite coating was developed to enhance wheat seed germination and early growth under abiotic stress. The coating improved structural stability, antibacterial activity, and stress tolerance. Germination trials confirmed significant improvements in the agronomic performance, highlighting its potential as a sustainable strategy for resilient seed performance.

Abstract

This research aimed to develop and evaluate titanium dioxide-embedded sodium alginate/chitosan-based active coatings for wheat seeds to enhance seed germination and early seedling growth. For this purpose, Alg-Cs-TiO₂ nanocomposite coatings were synthesized and applied to wheat seeds to improve germination, seedling growth, and resistance against abiotic stress. Chitosan (Cs) beads were initially reinforced with TiO₂ nanoparticles, and the beads were further coated with sodium alginate (Alg) to form Alg-Cs-TiO₂ beads. Characterization techniques, including scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and thermogravimetric analysis (TGA), confirmed the successful incorporation of TiO₂ into the Alg-Cs matrix, improving crystallinity, thermal stability, and structural integrity. Antibacterial activity assays demonstrated enhanced inhibition of Escherichia coli and Staphylococcus aureus, with Alg-Cs-TiO₂ beads exhibiting the highest antibacterial effectiveness. Seed germination trials showed that Alg-Cs-TiO₂ coatings significantly improved seedling length by 0.524 cm, coleoptile length by 3.19 cm, shoot length by 28.887 cm, root length by 17.8 cm, and root weight by 0.129 g compared to uncoated seeds. The TiO₂ nanoparticles facilitated UV absorption, stress tolerance, and pathogen resistance, contributing to enhanced plant growth. This study highlighted Alg-Cs-TiO₂ coatings as a sustainable and effective biopolymer-based approach for the improvement of wheat seed performance in challenging environmental conditions.