Effects of Integrated Nutrient Management on Rice Yield, Nutrient Uptake and Soil Fertility Status in Reclaimed Sodic Soils

A Field experiment was conducted on a reclaimed sodic soil at experimental farm of Central Soil Salinity Research Institute, Karnal to assess the possibility of improving productivity of rice under two levels of fertilizer N and P applications i.e. 75% recommended NP (90 kg N + 19.5 kg P ha⁻¹) and 100% recommended NP (120 kg N + 26 kg P ha⁻¹) with and without organic manures i.e. 10 t ha⁻¹ farmyard manure (FYM), 10 t ha⁻¹ sulphitation pressmud (SPM), in situ green manuring (GM) as Sesbania aculeata and 2.5 t ha^{− 1} wheat residue (WR). Application of N, P and organic sources significantly increased the no. of tillers, plant height and yield of rice over control. The maximum yield of rice was obtained in 100% NP+GM (6.42 t ha⁻¹) than 100% NP (5.31 t ha⁻¹) and 100% NP + wheat residue (6.02 t ha⁻¹) treatment. The 100% recommended NP with organic sources (FYM, PM, GM, and WR) recorded higher N uptake by 29.2, 29.4, 37.3 and 18.4%, respectively as compared to 100% recommended NP. The use of organic manure decreased soil pH and its combined use with fertilizers was significantly reflected in the build up of available N, P, K, organic carbon and DTPA– extractable Fe and Mn content of the soil.