Implementation of the Nitrates Directive and its influence on the baking value of winter wheat

The purpose of this work was to determine the effects of lowering nitrogen fertilization on the baking value of winter wheat cultivars and it also serves as a response to the implementa-tion of the Nitrates Directive. Nine wheat cultivars were tested, which represented four technological groups that are included in the Polish National List of Agricultural Plant Varieties. The wheat was cultivated over a period of two seasons as a two-factor field experiment designed to utilize the method of randomized blocks, in four replicates. Two distinct applications of nitrogen fertilizer were adopted in the experiment: 120 and 200 kg ha-1 N. The Zeleny index, the quantity of protein and gluten, and the alveograph char-acteristics were determined in order to assess the baking value of the wheat. Lowering the level of nitrogen fertilization to 120 kg ha-1 N caused a negative effect on the quality of the wheat, with regard to a lower Zeleny index, protein and gluten quantity. The alveograph parameters were affected by wheat cultivars while the nitrogen dose applied and the crop year had no effect. Lowering the degree of nitrogen fertilization of wheat crops to comply with the Nitrates Directive implementation may cause the production of wheat with a lower protein quantity which is a crucial parameter in grain trad-ing. However, the reduction in nitrogen fertilization causes only a slight, statistical non-significant reduction in the alveograph characteristics of wheat flour dough.