Study Of Foliar Application Of Nano Urea On Growth And Yield Of Mustard (Brassica Juncea L.) Under Timely And Late Sown Condition

Abstract

A field experiment was conducted during the Rabi season of 2022–23 at the Instructional Farm, IIAST, Integral University, Lucknow, to investigate the impact of foliar-applied nano urea on the growth, yield, and quality performance of mustard  under timely and late sowing conditions. The experiment was laid out in a split plot design with two sowing times (timely and late) in the main plots and five nitrogen management treatments in the subplots, using the RH-749 mustard variety. The nitrogen treatments included 100% recommended dose of nitrogen (RDN) through conventional urea, 100% RDN via nano urea, and various urea–nano urea combinations. Timely sowing significantly improved all measured parameters, including plant height, biomass accumulation, siliquae per plant, and seed yield. Among nitrogen treatments, 100% RDN through conventional urea yielded the highest values for growth and productivity indicators, with seed yield reaching 15.75 q/ha. A 25% substitution of urea with nano urea performed comparably, indicating enhanced nitrogen use efficiency. However, increasing nano urea beyond 50% adversely affected yield and oil content. The results suggest that partial integration of nano urea (up to 25%) with conventional nitrogen sources under timely sowing conditions is a promising approach for optimizing mustard production and sustaining nitrogen efficiency.