EN
In 1992-1995 field experiments of an ecological character were carried out on winter wheat in North-East Poland. Wheat was cultivated after horse bean in a Norfolk crop rotation system on the soil composed of medium-heavy and light clay, rich in assimilable nutrients (N, P, K, Mg), but moderately rich and poor in boron, copper and zinc. Four fe tilization variants were used: biodynamic manure in the third year of the consecutive effect, intensive mineral fertilization (350 kg NPK/ha), and a 5th control variant: natural soil fertility. Balanced fertilization in which nitrogen and phosphorus were applied in from of foliar nutrition, proved to be the most effective. 1 kg NPK applied in such a way yielded 14,6 kg of grain, whereas in the case of intensive fertilization the yield was only 7,6 kg, and with biodynamic manure - 6,5 kg of grain per 1 kg NPK. N, P, K, Mg and crude protein content (10,2-10,5%) was similar in all fertilization variants, but protein production was the highest with intensive mineral fertilization (865 kg/ha) and balanced fertilization (782 kg from 1 ha); it amounted to 639 kg/ha in the case of biodynamic manure. It was concluded that the variant consisting of balanced fertilization should be the one representing an alternative viz. pro-ecological plant fertilization. Its effect on the yield and grain quality were the optimal ones from an ecological point of view.