Nanostructures are increasingly used to mitigate various abiotic stresses in recent years. This study investigated the effects of zinc oxide nanostructures, titanium oxide nanostructures (TiO2 nanostructures) and zeolite (Zeo)-supported ZnTiO3 nanostructures on ‘Zard’ fig (Ficus carica L.) seedlings in alleviating the adverse effects of salinity stress. Fig plants were treated with 10 mg L-1 ZnO nanostructures, 15 mg L-1 TiO2 nanostructures, and 15 mg L-1 Zeo-supported ZnTiO3 nanostructures under normal conditions and 75 mM NaCl stress. Salinity stress increased Na⁺ levels by 134%, hydrogen peroxide (H2O2) concentrations by 45%, and electrolyte leakage percentage (EL%) by 45%, while significantly reducing root growth parameters. In contrast, treatment with Zeo-supported ZnTiO3 nanostructures significantly increased root fresh weight by 53% and dry weight by 48%, improved the chlorophyll index; soil plant analysis development values by 12%, boosted superoxide dismutase activity by 25% and glutathione peroxidase activity approximately ~2.8-fold, while reducing EL% and H₂O₂ concentrations by 22% each, thereby contributing to the enhanced salinity tolerance in salt-stressed fig plants compared with nanostructure-untreated plants. Although ZnO nanostructures and TiO2 nanostructures also improved some root system architecture (RSA) parameters under salinity stress, the Zeo-supported ZnTiO3 nanostructures were more effective. The results indicate that the enhanced efficacy composite Zeo-supported ZnTiO₃ nanostructure is more effective than individual treatments in enhancing salinity tolerance in fig seedlings by modulating key physiological, biochemical, and RSA traits. Combined ZnTiO3 nanostructures with zeolite substrate showed significantly greater effect in improving salt stress tolerance than the separate application of ZnO or TiO2 nanoparticles, indicating enhanced efficacy benefits in their combined use. Therefore, future studies should focus on scaling up their application under saline field conditions, assessing long-term environmental safety, and exploring their integration with precision agriculture technologies to further improve sustainable fig production under salinity stress.
