Foliar Spraying of Silicon and Titanium Nanoparticles: Biometrics and Mineral Nutrition of Maize

Purpose: Recent studies highlight the potential of silicon (Si) and titanium (Ti) nanoparticles (NPs) in agriculture, particularly for foliar application. This study aimed to evaluate the effects of foliar-applied Si and Ti NPs on biometric parameters, chlorophyll content, and nutrient uptake by maize. Methods: The experiment was conducted in a completely randomized design with four replications. Concentration of 0, 50, 100, and 200 mg L⁻¹ of Si and Ti were tested in both NP and bulk forms. Root length, root dry mass (RDM), shoot dry mass (SDM), SPAD index, and nutrient content in the SDM were determined. Results: The maximum root length (58 cm) was observed at the 24 mg L⁻¹ dose of TiO 2 NPs. Both SiO 2 and TiO 2 NPs increased shoot length and RDM, with optimal concentration ranging from 164 to 200 mg L⁻¹ for SiO 2 and from 50 to 86 mg L⁻¹ for TiO 2 . SPAD index increased with SiO 2 NPs up to 133 mg L⁻¹. TiO 2 NPs enhanced K content up to 120 mg L⁻¹ and increased P, Ca, Mg, Cu, and Zn concentrations. SiO 2 NPs raised P, Ca, and Mg contents but reduced Fe concentration up to 130 mg L⁻¹. Conclusions: Foliar-applied SiO 2 and TiO 2 NPs altered maize biometric and nutritional traits, indicating beneficial effects associated with both elemental composition and nanoscale properties.