Impact of titanium nanoparticles on germination and early growth of faba bean (Vicia faba L.)

This study explores the potential of biosynthesized titanium dioxide nanoparticles (TiO₂NPs), capped with phytochemicals from Zygophyllum simplex extract, in enhancing seed germination and related indices of faba bean (Vicia faba L.), aiming to support sustainable and biocompatible approaches in nano-agriculture. Specifically, the study assessed the impact of biogenic TiO₂NPs (average size ≈ 12.8 nm) on seed germination, early plant growth parameters such as root and shoot length, and germination percentage, as well as the activity of selected antioxidant and hydrolytic enzymes in faba bean. Seeds were soaked for 6 h in an aerated solution containing six concentrations of TiO₂NPs (1, 5, 10, 25, 50, and 100 µM), alongside a control group. Germination was conducted in dark at 25 ± 0.5 °C for six days. The results demonstrated that TiO₂NPs at concentrations up to 25 µM significantly enhanced germination percentage, seedling growth parameters, and increased the activities of antioxidant enzymes; catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD), as well as α-amylase and protease enzymes, total soluble sugar and protein content, in comparison with non-treated seeds. However, TiO₂NPs at a concentration of 50, and 100 µM significantly reduced germination rates, inhibited seedling growth, and decreased enzyme activities relative to the control. These findings suggest that nano-titanium, particularly at a concentration of 10 µM, effectively enhances germination potential, subsequent seedling growth, and enzyme activity in Faba beans. Further research on the impact of these nanoparticles on vegetative growth and yield could provide valuable insights based on the positive effects observed during germination and early seedling development.