Effect of nitrogen and ethrel on various physiological and yield attributes of mustard (Brassica juncea L.)

The mustard plants (Brassica juncea L. Czern and Coss) cv. ‘Alankar’, grown on a soil treated with 40, 60 and 80 kg N ha⁻¹, were sprayed with 0.02% ethrel (2-chloro-ethyl phosphonic acid) at flowering stage [60 days after sowing (DAS)] to observe the changes in leaf area index, net photosynthetic rate, nitrate reductase activity and plant dry biomass on 80, 100 and 120 DAS. At harvest, the pod number plant⁻¹, 1000-seed weight and seed yield were also recorded. Ethrel (0.02%) + 80 kg N ha⁻¹ treatment enhanced leaf area index, net photosynthetic rate, nitrate reductase activity, plant biomass by 75.5, 56.4, 72.1 and 39.1%, respectively, while pod number plant⁻¹, 1000-seed weight and seed yield were enhanced by 27.2, 5.6 and 71.9%, respectively.