Comparative Evaluation of Conventional and Nano Urea for Growth and Yield Performance of Sprouting Broccoli (Brassica oleracea L. var. italica Plenck)

Abstract

A field investigation was conducted during the rabi seasons of 2023-24 and 2024-25 at the Vegetable Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, to evaluate the comparative efficacy of conventional and nano urea on growth and yield performance of sprouting broccoli (Brassica oleracea L. var. italica Plenck). The experiment was laid out in a two-factor factorial randomised complete block design comprising three levels of soil-applied nitrogen (100%, 75% and 50% of the recommended dose of nitrogen [RDN]) and five foliar nitrogen treatments, viz., no spray, one or two sprays of nano urea @4 mL L-1, and one or two sprays of conventional urea @20 g L-1, along with an unfertilised control. Pooled analysis of the data revealed that soil-applied nitrogen positively influenced plant height, plant spread, average head weight and head yield. Foliar application of two sprays of conventional urea generally produced superior growth and yield compared with nano urea. The combination of 75% RDN with two foliar sprays of conventional urea recorded the highest pooled plant height and plant spread at 60 DAT (82.97 and 80.93 cm, respectively) and head yield per plot (19.43 kg), as well as the second-heaviest heads (433.27 g), and remained statistically at par with 100% RDN combined with two sprays of urea. Fertilised treatments significantly outperformed the unfertilised control. Thus, 75% RDN supplemented with two foliar sprays of conventional urea offers a promising nitrogen-management strategy for enhancing sprouting broccoli productivity under the Tarai conditions of Uttarakhand.