Effect of different nitrogen management options on nutrient uptake, biomass carbon sequestration and grain yield of maize-wheat system in reclaimed sodic soil

A field experiment was conducted to study the impact of different nitrogen (N) management options on the nutrient uptake, biomass carbon sequestration and yield of maize-wheat system in reclaimed sodic soil of the Trans-Gangetic Plains of India. Seven N management treatments - T1 [100% recommended dose of N (RDN) + 10 t ha(-1) farm yard manure (FYM)]; T2 (100% RDN); T3 (75% RDN + 25% N through FYM); T4 (50% RDN + 50% N through FYM), T5 (25% N through FYM); T6 (50% N through FYM) and T7 (control; No N) were tested. Maximum nutrient uptake, biomass carbon sequestration and yield of maize-wheat system were reported in 100% RDN + FYM treatment. Total biomass carbon sequestration and yield were significantly higher by 47.8% and 30.4%, respectively in 100% RDN + FYM as compared to control treatment. However, 100% RDN + FYM was statistically at par with the 100% RDN, 75% RDN + 25% N through FYM, and 50% RDN + 50% N through FYM treatments for both these variables. Nutrient uptake, total carbon sequestration and yield in 50% N through FYM and 25% N through FYM were insignificantly higher as compared to control, but significantly lower than the 100% RDN treatment. Results indicated that the addition of FYM with RDN increased the nutrient uptake, biomass carbon sequestration and yield of maize-wheat system. Higher biomass carbon sequestration and sustainability to maize and wheat cropping system is need of the hour in the study area.