Effectiveness of mineral fertilizer use on calcareous chernozems

In order to ensure an efficient use of mineral fertilisers and to increase yield and quality of crops, a thorough evaluation of various combinations of mineral fertilisers under field condition is necessary. A three year field experiment was conducted on calcareous chernozem soils with wheat and sunflower in Rustov state of Russia (i) to evaluate the effect of various combinations of mineral fertilisers on yield and quality and (ii) to determine optimum mineral fertiliser combination, which will finally result in a bio-energy efficient and economically feasible increase in yield and quality. Results of this study indicate that maximum yield and optimum quality of wheat could be obtained at N90P60K60. For sunflower the treatments N60P60K60 and N90P60K60 resulted in the highest yields. At medium input of NPK fertiliser (N60P60K60) the bio-energetic coefficient for wheat and sunflower ranged from 3.2 to 3.5 in this experiment. These calculations also indicated that the bioenergetic coefficient tended to decrease with increased levels of mineral fertiliser application.