Growth Performance of Maize (Zea mays L.) as Influenced by Foliar Application of Nano Urea under Field Conditions

Abstract

A field experiment was conducted during the kharif season of 2025 at Instructional Farm-1, GIET University, Gunupur, Odisha, to investigate the influence of foliar application of IFFCO nano urea on the pre-harvest growth parameters of maize (Zea mays L.) hybrid 'Virat'. The experiment was laid out in a Randomised Block Design with eight treatments and three replications. Treatments comprised four levels of the recommended dose of nitrogen (0%, 33%, 66% and 100% RDN) supplied through conventional urea, each with and without foliar spray of nano urea @ 4 ml L⁻¹ at the peak vegetative stage (knee-high to pre-tasselling), against a recommended dose of 120:60:60 kg N:P₂O₅:K₂O ha⁻¹. Growth parameters, including plant height, number of leaves per plant, dry matter accumulation, crop growth rate (CGR), relative growth rate (RGR), relative leaf water content (RLWC), days to 50% tasselling, days to 50% silking and days to physiological maturity, were recorded at various stages. Differences among treatments were non-significant at 30 DAS for most parameters, indicating uniform initial crop establishment. Significant differences emerged from 60 DAS onwards. Treatment T₈ (100% RDN + nano urea @ 4 ml L⁻¹) recorded significantly higher plant height (198.73 cm), dry matter accumulation (260.41 g plant⁻¹), number of leaves (14.46 per plant) and CGR (17.05 g m⁻² day⁻¹ during 60–90 DAS) at harvest; these values were statistically at par with those of T₄ (100% RDN through urea alone). Phenological parameters, including days to tasselling (58), silking (61) and maturity (82), were also highest under T₈, indicating a prolonged vegetative phase. RLWC remained non-significant across all growth stages. The results indicate that combined application of the recommended nitrogen dose with nano urea foliar spray is an agronomically effective strategy for enhancing vegetative growth and biomass accumulation in kharif maize. This manuscript provides field-based evidence on the interactive effects of conventional urea and nano urea in maize under the agro-ecological conditions of southern Odisha. It contributes to the growing evidence on nanotechnology applications in agriculture by demonstrating potential improvements in nitrogen use efficiency and vegetative growth parameters. The findings offer practical insights for sustainable nutrient management, which may help reduce environmental impacts associated with excessive fertiliser use while maintaining or enhancing crop productivity. Furthermore, the detailed growth analysis, including CGR, RGR and phenological responses, provides data for modelling crop responses to nano-fertilisers in tropical environments.