Re-visiting of nitrogen and sulphur requirements in Indian mustard (Brassica juncea) under irrigated conditions

Present study was carried out during 2018–19 and 2019–20 at ICAR-Directorate of Rapeseed-Mustard Research, Bharatpur, Rajasthan to evaluate the effect of nitrogen (N) and sulphur (S) nutrition on production efficiency, water productivity, and economics of Indian mustard [Brassica juncea (L.) Czern & Coss.] under irrigated conditions. The experiment was conducted in a split plot design with 5 nitrogen levels (0, 60, 80, 100 and 120 kg/ha) as the main plot treatment and 4 sulphur levels (0, 20, 40, and 60 kg/ha) as subplot treatment with 3 replications. Results revealed that the application of 120 kg N/ha recorded the highest plant height (205 cm), leaf area index (5.4), number of leaves/ plant (47.3), primary branches/plant (6.8), secondary branches/plant (18.9), SCMR (46.5), number of siliquae/plant (382), number of seeds/silique (18), stem girth (6.65 cm), test weight (5.79 g) and seed yield (3.04 t/ha). Among the different S levels, the maximum values of growth and physiological parameters, yield attributes and seed yield were recorded at 60 kg S/ha (2.71 t/ha). Similarly, production efficiency (22.1 kg/ha/day) and water productivity (1.53 kg seed/m3) were found higher than 120 kg N/ha and 60 kg S/ha. The highest net monetary returns and Benefit cost (B: C) ratio were recorded with 120 kg N/ha and 60 kg S/ha.Thus, the application of N and S may be revised to 120 and 60 kg/ha, respectively for Indian mustard in the irrigated semi-arid climates to achieve higher productivity, efficiency and profitability.