Influence of different nutrient management practices on productivity, profitability and nutrient dynamics in basmati rice (Oryza sativa) - wheat (Triticum aestivum) cropping systems in western Indo-Gangetic Plains of India

A field investigation was carried out at ICAR-Indian Institute of Farming Systems Research, Modipuram during 2013-15 to devise the best nutrient management strategy in basmati (Oryza sativa L.)-wheat (Triticum aestivum L. emend Fiori and Paol) cropping system. Investigation used six nutrient management practices, viz. 100% organic; 75% organic + innovative practices; 50% organic + 50% inorganic; 75% organic + 25% inorganic; state recommendation and 100% inorganic. Grain yield and nutrient uptake of basmati rice and wheat were found at par under organic (100% organic and 75% organic + innovative practices) and integrated nutrient management practices (50% organic + 50% inorganic and 75% organic + 25% inorganic), however it was significantly higher compared to 100% inorganic nutrient management. Organic nutrient management, i.e. 100% organic and 75% organic + innovative practices resulted in 42.4 and 37.7% higher grain yield in case of basmati rice and 29.3 and 39.7% higher yield in case of wheat, respectively over 100% inorganic; besides being superior in terms of soil available N, P, K and organic carbon. Additional net returns to the tune of (sic) 53.2 x 10(3)/ha and (sic) 59.7 x 10(3)/ha from basmati rice-wheat cropping system was recorded under 100% organic and 75% organic + innovative practices, respectively over 100% inorganic. Nutrient management through 75% organic + innovative practices in basmati rice-wheat cropping system resulted in (sic) 6.5 x 10(3)/ha additional returns over 100% organic nutrient management and it also scored highest in terms of nitrogen use efficiency of both basmati rice (48.5 kg/kg N) and wheat (38.1 kg/kg N). A significantly higher residual soil fertility in terms of available N, P, K and organic carbon in soil as compared to 100% inorganic nutrient management was also observed.