Nitrogen Uptake by Winter Wheat (Triticum aestivum L.) Depending on Fertilizer Application

The influence of the injection of nitrogen fertilizers with the CULTAN system (Controlled Uptake Long Term Ammonium Nutrition) on nitrogen uptake by winter wheat (Triticum aestivum L.) was observed at small-plot field experiments under conditions of the Czech Republic (central Europe) during 2007-2013. The CULTAN system consisting in the injection of all the nitrogen in one dose was compared with conventional broadcast surface fertilization which is carried out in three partial nitrogen doses. The total nitrogen dosage was 150 kg N.ha(-1). If the CULTAN fertilization was carried out at the beginning of tillering of winter wheat (BBCH 22) instead of at the end of tillering (BBCH 29), the CULTAN-treated winter wheat did not suffer from nitrogen deficiency at the BBCH 45 (boot stage) and BBCH 51 (beginning of heading) growth stages. Nitrogen utilization efficiency and biomass production efficiency were significantly higher with the CULTAN treatment compared to the conventional fertilization whereas nitrogen uptake efficiency tended toward lower values with the CULTAN treatment. Nitrogen use efficiency (NUE), post-heading nitrogen uptake, the contribution of nitrogen translocation to the total nitrogen in grain, the partial factor productivity of nitrogen as well as grain yield were not significantly influenced by the CULTAN system. Prolonged nitrogen uptake from the soil with the CULTAN treatment resulting in delayed plant senescence was not confirmed. Neither an application of sulphur-containing fertilizer nor the increased dosage of nitrogen (200 kg N.ha(-1)) positively affected the studied parameters.