Efficiency of Nitrogen Fertilization of Winter Wheat Depending on Sulfur Fertilization

Optimization of fertilization enables to obtain a yield of high quality and quantity, brings economic profits, and reduces environmental threats. The aim of the three-year field experiment was to determine the efficiency of fertilization with a new fertilizer available on the Polish market and containing nitrogen (N) and sulfur (S) in proportions designed for cereals cultivation (30% N and 6% S as ammonium nitrate and ammonium sulfate). Other treatments included no fertilization; fertilization with ammonium nitrate (34% N); fertilization with standard nitrogen and sulfur fertilizer with N supplementation with ammonium nitrate. Nitrogen doses were 150, 200, and 250 kg N ha(-1). Sulfur was applied in doses of 30, 40, and 50 kg S ha(-1). A beneficial effect of using fertilizer containing N and S in proportions designed for cereals cultivation was observed. The highest mean optimal nitrogen dose and maximum winter wheat yield were recorded for the new fertilizer (217 kg N ha(-1)and 8251 kg ha(-1), respectively). Sulfur supplementation with the new fertilizer significantly increased apparent nitrogen recovery (mean values 48.9%, 44.6%, and 40.6% for doses 150, 200, and 250 kg N ha(-1), respectively), agronomic efficiency (11.1 and 8.6 kg kg(-1)N for doses 200 and 250 kg N ha(-1), respectively), and physiological efficiency (24.7 kg kg(-1)N for dose 200 kg N ha(-1)).