International Journal of Farm Sciences

A long term experiment was conducted with the objective of assessing the impact of continuous application of chemical fertilizers and manures on properties of soil, key indicators of soil quality and yield under rice (Oryza sativa)-wheat (Triticum aestivum) cropping system. The experiment was conducted in randomized block design since 1999 on vertisols at the same site and with the same randomization at Raipur in central India as one of the centers of AICRP on long-term fertilizer experiment. Results showed that application of 150 percent NPK recorded highest yield (5.06 tons/ha) which was on par with 100 percent NPK + FYM treatment (4.85 tons/ha). The soil pH and EC were not changed but the organic carbon, available nutrient contents of the soil and plant growth parameters were markedly changed.. The available N, P and K were gradually depleted in all the treatments but the magnitude of depletion was less in the treatments which received N, P and K. Thus the balanced use of fertilizers continuously either alone or in combination with organic manure is necessary for sustaining soil fertility and productivity of rice crop.