Effect of source and time of nitrogen application on growth parameters, phenology and yield of Zero-tillage wheat (Triticum aestivum L.)

The biggest challenges in current world agriculture are low nutrient use efficiency (NUE) (≤ 40%) and environmental pollution due to improper fertilizer management and heavy tillage. To address these challenges, a field experiment was conducted during the Rabi seasons of 2022-23 and 2023-24 in CCS Haryana Agricultural University, Hisar (India). The two factor’s experiment laid out in split plot design with three replications consisted of 20 treatment combinations comprising five different N doses viz., 50% RDN through Urea + 50% RDN through Nano Urea; 62.5% RDN through Urea + 37.5% RDN through Nano Urea; 75% RDN through Urea + 25% RDN through Nano Urea; 100% RDN through Urea and Control in the main plots and four different N application times viz., 1/2 as basal application + 1/2 after 1st irrigation; 1/2 after 1st irrigation + 1/2 after 2nd irrigation; 1/3 as basal + 1/3 after 1st irrigation + 1/3 after 2nd irrigation; 1/3 as basal + 1/3 before 1st irrigation + 1/3 before 2nd irrigation in the sub plots. The result revealed that application of 100% RDN through urea not only delayed wheat flowering and maturity but also it significantly increased the growth parameters (plant height, dry matter accumulation, number of tillers) and grain yield of wheat which was followed by application of 75% RDN through Urea + 25% RDN through Nano Urea. Among time of N application three split doses viz., 1/3 as basal + 1/3 after 1st irrigation + 1/3 after 2nd irrigation recorded significantly higher growth parameters and yields of wheat as compared to two split doses i.e., 1/2 as basal application + 1/2 after 1st irrigation during both consecutive years.