The influence of fertilization and soil and climate conditions on the grain yield of winter wheat

Long-term stationary fertilizer trials were performed at three different sites in order to study the subsequent effects of manure and full mineral fertilization. Dry matter yields of winter wheat grown after red clover were evaluated over the years 2003–2006. In the nil variant without any fertilization for the past 47–51 years, the basic grain yields were decreasing with the higher altitude. Three-year average yields varied from 3.39–8.09 t ha−1. The site productivity accounted for almost 80% in the Greyic Phaeozem and only about 53% in the Stagno-Gleyic Cambisol. The effect of mineral fertilization was the highest in the Stagno-Gleyic Cambisol, up to about 39%. The effect of weather conditions in individual years strongly differed in individual sites. The results have confirmed a complex of effects and interactions among various factors that affect winter wheat grain yields.