Can foliar nano-fertilization reduce conventional fertilizer requirements in rice?

Abstract

Improving nutrient use while reducing dependence on conventional fertilizers is important for sustaining rice productivity. A field experiment was conducted to evaluate the effect of integrating reduced rates of recommended fertilizer dose (RDF) with foliar nano urea and nano di-ammonium phosphate (DAP) on growth, yield, nutrient accumulation, grain quality and economic returns of rice. Nutrient management significantly influenced crop growth, yield and nutrient uptake. Application of 75% RDF + two foliar sprays each of nano urea and nano DAP produced the highest dry matter accumulation, panicle number, grain and straw yield, and outperformed 100% RDF. Grain yield under this treatment increased by 59.2% over the control and 12.6% over 100% RDF. Grain N, P and K concentrations increased by 8.00, 54.0 and 32.0%, respectively, over the control, while their corresponding uptakes increased by 78.0, 139 and 83.0%. Grain protein content also increased by about 11.0%, whereas amylose content was not significantly affected. Grain N content showed a strong positive relationship with protein content (R 2 = 0.94), while the relationship with grain P was comparatively weaker (R 2 = 0.58). The highest net return and return on investment were also obtained with 75% RDF + nano urea + nano DAP. The findings indicate that foliar nano-fertilization can complement reduced conventional fertilizer inputs and improve productivity, nutrient accumulation and economic returns in rice.