Influence of Biodegradable Polymer Coated Urea on Nitrogen Uptake and Utilization of Maize (Zea mays L)

Controlled release nitrogen fertilizers could be an excellent management approach for improving nitrogen fertilizer efficiency. The present study aimed to investigate the effect of coated urea fertilizers to increase nitrogen uptake and utilization of maize. The nitrogen use efficiency of maize from various biodegradable polymer-coated urea fertilizers, such as palm stearin coated urea (PSCU), pine oleoresin coated urea (POCU), and humic acid coated urea (HACU), was determined in a pot culture experiment conducted at the Department of Soil Science and Agricultural Chemistry, Tamil Nadu Agricultural University, Coimbatore, during 2021. The coating materials have been coated on urea with different coating thicknesses, viz., PSCU - 5, 10, 15%, POCU – 2, 4, 6%, and HACU - 5, 10, 15%. Among all the treatments, T11: HACU 15% produced highest grain yield (72.0g plant-1) followed by T7: POCU 4% (69.7 g plant-1) and T4: PSCU 10% (69.0g plant-1). In terms of dry matter production, T10: PSCU 10% produced maximum dry matter (186.5g plant-1), followed by T11: HACU 15% (186.2 g plant-1), and T7: POCU 4% (185.3g plant-1). The nitrogen uptake by the maize plant was higher in T7: POCU 4 % (1.62g plant-1), followed by T11: HACU 15% (1.59 g plant-1) and T4: PSCU 10% (1.59g plant-1). Irrespective of treatments, the highest nitrogen utilization by the maize crop was found in T7: POCU 4% (73.9%) followed by T4: PSCU 10% (71.1%) and T11: HACU 15% (70.9%) treatments. When compared to uncoated urea fertilizer, all coated urea fertilizers outperformed uncoated urea fertilizer in terms of grain yield, dry matter accumulation, and nitrogen uptake. To improve the nitrogen use efficiency, coated urea fertilizers prove to be a promising alternative to uncoated urea fertilizers.