Effect of gypsum application in conjunction with green manuring and zinc sulphate on yield of rice (Oryza sativa) and health of a sodic soil

A field experiment was conducted during two consecutive kharif seasons of 2009 and 2010 at Kanpur on a clay loam, sodic soil to assess the combined effect of gypsum in conjunction with green manuring and double dose of zinc sulphate on soil health, nutrient uptake and yield of rice (Oryza sativa L.). Variety CSR13 was superior to Sarjoo 52 in terms of uptake of NPK and Zn, yield attributes, and grain and straw yields. Application of gypsum @ 50 and 100% of gypsum requirement (GR) significantly enhanced nutrient uptake, yield components and grain yield over the control during both the cropping seasons. The response was more pronounced when gypsum 50% of GR was applied in conjunction with green manure (GM) at 10t ha-¹ or ZnSO₄ (60 kg ha-¹). The response of gypsum 50% of GR + GM @10t ha-¹ on the yield and yield attributes was at par with the treatment receiving gypsum 50% of GR + ZnSO₄ (60 kg ha⁻¹) in both the rice cultivars.