Integrated nutrient management for sustaining maximum productivity of rice - wheat system under Punjab conditions

The effects of conjunctive use of farm yard manure (FYM), green manures (GM), crop residues incorporation (CRI) and inorganic fertilizers on the sustainability and productivity of rice-wheat system were investigated in a long term fertilizers experiment conducted at experimental farm of Punjab Agricultural University, Ludhiana. Higher productivity is obtained when 50 per cent NPK is applied through chemical fertilizers in combination with 50 per cent N through FYM or green manure to get grain yield of 11.0 t/ha in rice-wheat system over time. The incorporation of FYM, GM and CRI in the soil has beneficial effect on soil health by improving physico-chemical properties besides supplying the macronutrients like N, P and K and increasing the availability of the micronutrients like Zn, Cu, Fe and Mn in the soil. Moreover, the results obtained during 2002–05 reported that the addition of these manures decreased the bulk density and increased the levels of organic carbon, field capacity, permanent wilting point and available soil moisture.