Journal of the Indian Society of Soil Science

A field experiment was conducted at the Central Soil Salinity Research Institute Regional Research Station, Lucknow during 1999–2002. Effect of irrigation scheduling and integrated use of organic manure and inorganic fertilizers for maximizing yields of rice-wheat cropping system in the gypsum-amended sodic soils was studied. Grain yield of rice was significantly higher under continuous submergence over the irrigation at 4 days after disappearance of pounded water (DADPW). However, the grain yield with 2 - DADPW was at par with continuous submergence. The growth and yield of rice were significantly higher under 100% NPK + green manure dhaincha (Sesbania aculeata) followed by 100% NPK + 10 t sulphitation pressmud cake (SPMC) ha⁻¹ in comparison to other treatments under continuous submergence and 2-DADPW. Irrigation amounting to 57.5 cm at 2 -DADPW saved 24% of water over the continuous submergence without reducing the grain yield. Growth and yield of wheat were significantly higher with the application of 100% NPK with residual effect of green manure (T5) followed by SPMC in comparison to other treatments. Wheat yield was higher with 4 irrigations applied at critical root initiation (CRI), tillering (T), jointing (J) and milking (M) stages as compared to 3 irrigations at CRI, T and M stages. Integrated use of inorganic fertilizers and organic manures reduced soil pH from initial 10.2 to 9.0 in 0 -15 cm soil layer. Organic carbon content (2.6 g kg⁻¹) and infiltration rate of (1.5 mm h⁻¹) were higher in case of 100% NPK + green manuring.