We can decrease the ecologic impacts on wheat yield, since winter wheat belongs to the group of crops which react positively to fertilisation. Therefore, by providing adequate nutrient supply level, it is possible to reduce the negative effects to a different extent. The extent of this reduction depends on the nutrient reaction of the given variety and the extent of the impact of ecologic factors. The yield and nutrient reaction of five winter wheat varieties of different genotypes (GK Öt halom, Lupus, Pannonikus, Mv Toldi, Genius) were examined on Hajdúság chernozem soil in different fertilisation treatments and three years. Our research findings showed that the genetically determined maximum fertility of the five wheat varieties examined by us was significantly influenced by the three examined crop years. Of the three crop years, the impact of the 2011 crop year was the most favourable, while dry and warm year of 2012 had a slight negative impact on wheat yield. The highest and most negative effect was imposed in 2010 when there was a significant amount of precipitation and the weather was also colder. The highest fertiliser utilisation ability was obtained in 2011 in the case of higher fertiliser levels, while we obtained lower yields both in the control and the higher fertiliser treatments in the dry year of 2012, when the utilisation of fertiliser by crops was lower and the weather was drier and warmer. In comparison with 2011 and 2012, we obtained the lowest yield both in the control and the higher fertiliser treatments in the extremely rainy year of 2010 which shows that the different varieties can tolerate the impact of the drier and warmer crop year of 2012 more and it could be decreased by providing higher amount of nutrients. On the contrary, the impact of a high amount of rainfall and colder ecologic conditions in 2010 could be reduced only to a significantly lower extent.

Keywords: winter wheat, crop year, yield