Effects of Nanoscale Silica Particles on Nitrogen, Phosphorus, and Potassium Content and Uptake in Rice

Abstract

Silica nanoparticles (SiNPs) are being examined as foliar inputs because silicon can influence plant growth, stress responses, and nutrient acquisition. This pot experiment evaluated the effects of foliar-applied SiNPs on nitrogen (N), phosphorus (P), and potassium (K) content and uptake in rice. The NLR 34449 rice variety was grown during the 2021 kharif season under ten treatments comprising a distilled-water control, the recommended dose of fertiliser (RDF), RDF with silicic acid at 4 mL L⁻¹, and RDF with SiNPs at 50, 100, 200, 400, 600, 800, or 1000 ppm. Foliar treatments were applied at 25 and 50 days after transplanting. Nutrient content and uptake were determined in straw and grain at harvest. The treatment comprising RDF with SiNPs at 200 ppm (T6) recorded the highest N, P, and K contents and uptake. In straw and grain, respectively, T6 recorded N contents of 0.62% and 1.36%, P contents of 0.16% and 0.34%, and K contents of 1.39% and 1.30%. Corresponding uptake values were 189.51 and 306.60 mg pot⁻¹ for N, 49.62 and 76.70 mg pot⁻¹ for P, and 424.72 and 293.41 mg pot⁻¹ for K. Under the conditions of this pot experiment, foliar application of SiNPs at 200 ppm with RDF was associated with improved macronutrient content and uptake in rice.