Evaluation of grain yield properties of wheat depending on long-term fertilization on vertisol soil

To determine the effect of vegetation season and fertilization on the yield and yield components of winter wheat, a field experiment was conducted at the Small Grains Research Center in Kragujevac (Serbia) to examine eight fertilization treatments during three growing seasons. The experimental study was performed on a degraded acidic vertisol. Annually, nitrogen fertilization rate was 80 kg ha-1 N, which was applied in combination with phosphorus (60 kg ha-1 and 100 kg ha-1) and potassium (60 kg ha-1). Grain yield, 1000 grain weight, and hectoliter weight were analyzed. Grain yield in all treatments in the 2014/15 growing season was significantly higher than in the other years of the study. The yield, thousand grain weight, and test weight of winter wheat significantly varied across years and treatments. The highest yield was achieved in the treatment NPK, with phosphorous applied at 100 kg ha-1 (4.024 t ha-1). Thousand grain weight was the highest in N80P60K60 (39.06 g). During the test, significantly higher values of test weight were found in P60 (76.36 kg hL-1). The statistical analysis showed a highly significant effect of year on grain yield, thousand grain weight, and test weight. Fertilization had the most significant impact on grain yield. Positive and highly significant correlations between yield and thousand grain weight were found in all investigated treatments, except for the control and the variant fertilized with 60 kg ha-1 of phosphorus, where significant correlations were found.