Bhanu Singh, Abhineet, Dhruvendra Singh, Sachan, Shashi Bhushan and Sandeep Kumar Yadav
Abstract
Mustard (Brassica juncea L.) productivity in the Indo-Gangetic Plains is significantly influenced by crop establishment technique and nitrogen management strategy. A two-year field investigation (Rabi 2023-24 and 2024-25) was conducted at Integral University, Lucknow, to evaluate the effects of three sowing methods and four nitrogen management regimes on plant height, leaf area index (LAI), and seed yield of mustard. The experiment was laid out in a split-plot design with ridge sowing, flat sowing, and broadcasting in main plots, and nitrogen treatments consisting of 100% RDN via urea, three nano-urea sprays, 75% RDN +1 nano spray, and 50% RDN + 2 nano sprays in subplots. Flat sowing significantly enhanced plant height from 60 DAS onward and recorded maximum height at harvest (148.53 and 148.58 cm during 2023-24 and 2024-25, respectively). Leaf area index at 90 DAS was also highest under flat sowing (3.27) compared to ridge sowing (3.03) and broadcasting (2.56). Seed yield followed a similar trend, with flat sowing producing 17.21 and 17.19 q ha-¹ across two seasons, representing nearly 17% higher yield than broadcasting. Among nitrogen regimes, 100% RDN recorded the highest plant height (150.43 cm), LAI (3.60 at 90 DAS), and seed yield (17.13 q ha-¹), but 75% RDN + one nano spray maintained statistically comparable yield (16.16 q ha-¹). The findings indicate that flat sowing combined with partial nano-urea supplementation can sustain mustard productivity while improving nitrogen use efficiency under Indo-Gangetic conditions.