Nitrogen management for improving productivity, nutrient uptake and economics of sesame (Sesamum indicum L.) under North Gujarat 

Abstract

A field experiment was conducted during kharif 2024 at the Agronomy Instructional Farm, Chimanbhai Patel College of Agriculture, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar (Gujarat), to evaluate the effect of nano urea on growth, yield and nutrient uptake of sesame (Sesamum indicum L.). The experiment was laid out in a Randomized Block Design with seven treatments and four replications on loamy sand soil low in available nitrogen and organic carbon and medium in available phosphorus. Application of 75% RDN + 2% urea foliar spray at 30 and 45 DAS (T₄) recorded the highest plant height (164.6 cm), number of capsules/plant (45.10), number of seeds/capsule (56.45) and test weight (3.38 g). The same treatment produced significantly higher seed yield (743 kg/ha) and stover yield (1556 kg/ha). Oil content was not significantly affected by treatments; however, T₄ recorded the maximum oil yield (391.6 kg/ha) at harvest. Nutrient concentration and uptake were also superior under T₄, with seed nitrogen content of 2.83%, stover nitrogen content of 1.170%, seed phosphorus content of 0.454% and stover phosphorus content of 0.251%. Maximum nitrogen uptake by seed (20.72 kg/ha) and stover (14.06 kg/ha) and phosphorus uptake by seed (3.58 kg/ha) and stover (4.72 kg/ha) were recorded under this treatment. Post-harvest available soil nitrogen (159.3 kg/ha) and available P₂O₅ (41.82 kg/ha) were numerically higher under T₄, although the differences were statistically non-significant. Economically, T₄ recorded the highest gross realization (₹70,655/ha), cost of cultivation (₹35,251/ha), net realization (₹35,404/ha) and benefit ratio (2.00), followed by T₁ (gross realization ₹68,559/ha, net realization ₹33,038/ha and B ratio 1.93) and T₆ (gross realization ₹65,035/ha, net realization ₹29,806/ha and B ratio 1.85). This study concluded that under North Gujarat conditions, application of 75% RDN (37.5 kg N/ha) + 2% urea foliar spray at 30 and 45 DAS along with 25 kg P₂O₅/ha and 20 kg S/ha is agronomically and economically superior for sesame, while 75% RDN + nano urea @ 4 ml/L at 30 and 45 DAS can partially substitute conventional urea without yield penalty.