Effect of high nitrogen doses on yield, quality and chemical composition grain of winter wheat cultivars

Nitrogen fertilization is the basic element of a wheat cultivation technology, affecting the volume and quality of grain yield. The aim of this study, conducted in 2016-2019, was to assess the yield, quality parameters and chemical composition of the grain of hybrid cultivars fertilized with higher doses of nitrogen compared to a winter wheat population cultivar. The experiment was established on brown peat with the textural composition of silt loam (2016/2017 and 2018/2019) and clay loam (2017/2018). The soil was classified as a Fluvic Cambisol (CMfv). The first factor studied was nitrogen fertilization at doses: N150 – 150 kg ha-1 (three applications: 60+50+40) and N200 – 200 kg ha-1 (four applications: 60+80+40+20). The second factor was four cultivars of winter wheat: hybrid cultivars Hyking, Hypocamp and Hyvento, and a population variety Artist. The grain of the hybrid cultivars had good quality parameters (Hyking, Hyvento) and higher yields as well as a greater content of iron, copper, zinc and phosphorus in the grain (Hypocamp) compared to the population cultivar. The weather conditions with less rainfall, including a very dry period during wheat grain formation and maturation, depressed the grain yield but resulted in better quality traits and a higher content of macro- and micronutrients (Fe, Zn, Cu) in the grain. The application of a nitrogen dose of 200 kg ha-1 compared to 150 kg ha-1 caused an increase in the yield and quality of the hybrid wheat grain, without differentiating the mineral composition of grain in terms of the content of K, Ca and Mg as well as Zn and Mn.