The aim of the study was to verify whether new, intensive and commonly grown winter wheat cultivars in Poland differ significantly in Cu efficiency. Winter wheat is considered as one of the most sensitive agronomic species to Cu deficiency. Copper fertilization of wheat seems to be a necessity in our country due to common Cu deficiency in Polish soils.

In 2004-2006, three field experiments were conducted in the Experimental Station Osiny in Eastern Poland, where the response of five winter wheat cultivars to foliar copper application was tested. Copper was applied in the form of CuSO₄·5H₂O at a rate of 305 g ha^-1 Cu. Fertilization was performed in spring during the full tillering stage of growth. Analysis of variance was used for statistical calculations. The means were compared using Tukey’s test.

It was demonstrated that the five cultivars responded differently to the Cu fertilization, with a medium content of this element in soil. A single Cu spray caused 5-9% increase in grain yield in three out of the five tested cultivars. The other two cultivars did not show any significant yield increase in response to copper application. Besides, all the cultivars accumulated different quantities of copper in plant tissues, such as shoots and grain. The field trials have proven that winter wheat cultivars are diverse in their nutritional demand for copper. The necessity of winter wheat fertilization with Cu depends not only on the concentration of this nutrient in soil, but also on the tolerance of a given wheat cultivar to copper deficiency.