Effect of mineral and organic-mineral fertilizers on yields of crops and on soil fertility factors

Abstract

The use of adequate amounts of fertilizers is important for soil and crop management. The objective of this study was to determine the effect of mineral and organic-mineral fertilizers and of poultry manure on soil fertility factors and on yield of wheat, soybeans, and oats. Mineral sources of NPK were ammonium sulphate, triple superphosphate and potassium chloride and organic sources were lignite, peat and poultry manure. Significant differences were obtained between mineral and organic-mineral fertilizers in soil P in five samplings. No differences were determined in eight samplings in other soil fertility factors (pH in water, pH in SMP buffer solution, K, organic matter, and exchangeable Al and Ca+Mg). Poultry manure applied to the soil without any previous treatment promoted similar yields as mineral fertilizers. Average yields from plots receiving equal amounts of NPK either through organic or mineral sources, were not statistically different. However, the cost per unit NPK of the organic-mineral fertilizers was about twice as much as that of mineral fertilizers.