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Synthesized TiO2 nanoparticles mitigating salinity stress in okra plants via foliar application
Mehmood Khan
Bilal Ahmad
Ikram Ullah
Muhammad Ayub Khan
Sara Begum
Sara Bibi
Attaullah Khan
Mohsin Ali
Shahab Khan
Noor Ul Islam
Journal of Polymer Science and Engineering 2026, 9(1), 026100004; https://doi.org/10.24294/jpse026100004
Submitted:08 Mar 2026
Accepted:11 Jun 2026
Published:30 Jun 2026
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Cite This Article
Abstract

Titanium dioxide nanoparticles (TiO₂ NPs) are increasingly recognized for their potential to enhance plant growth under abiotic stress conditions. In this study, TiO₂ NPs were synthesized via a modified sol–gel method. The successful formation of anatase TiO₂-NPs with uniformly quasi-spherical morphology was confirmed using multiple characterization techniques, including X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Raman spectroscopy. Furthermore, we investigated the effects of foliar application of prepared TiO₂ NPs at 100 and 150 ppm on okra (Abelmoschus esculentus) grown under salt stress (100 ppm NaCl). The target variables evaluated included plant height, number of leaves, fresh and dry biomass, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, sugar content, and proline accumulation to determine the role of TiO2 NPs in salt stress mitigation. Salinity negatively affected all measured agronomic and physiological traits; however, treatment with TiO₂ NPs mitigated these adverse effects. Treated plants exhibited improved plant growth and yield-related characteristics, alongside higher concentrations of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids. Among the tested concentrations, 150 ppm TiO2 NPs showed the most pronounced improvement in growth, photosynthetic pigments, and yield performance under saline conditions. These findings indicate that foliar application of TiO2 NPs, particularly at 150 ppm, may play an important role in alleviating the detrimental effects of salinity stress on okra. Statistical analysis was performed using two-way ANOVA to assess the effects of variety, treatment, and their interaction, followed by Tukey’s HSD test for mean separation at p ≤ 0.05 using IBM SPSS Statistics.

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