DEPENDENCE OF PHYTOSANITARY CONDITIONS OF CROPS AND GRAIN YIELD OF WINTER WHEAT IN THE CROP ROTATION SYSTEM ON APPLICATION LEVEL OF CHEMICALS

Abstract

The article presents the study results of the field experiments on chemicals impact on phytosanitary conditions of crops and grain yield of winter wheat. Winter wheat was grown in a long-term crop rotation by the following scheme: potatoes, spring barley, pea- vetch-oat mix for green fodder, winter wheat. Phosphorus and potash fertilizers (P60K90) were applied as the background one. Nitrogen fertilizers in the form of ammonium nitrate were used on the experiment variants at the rate of N34.6 – N69.2 and N103.8. The herbicide Agritox, fungicide Alto and microelement cuprous sulphate were applied in ac-cordance with the scheme of the experiment. The statistical processing of experimental data proved that no harmful impact of pesticides on the productivity of winter wheat was observed in the years of the weak development of weeds and harmful phytopathogens. Regulating the phytosanitary condition of crops due to the winter wheat in the crop rotation, and the application of the herbicide Agritox at the rate of 1.5 kg/ha and the fungicide Alto (250 g/ha) and cuprous sulphate (350 g/ha), it is possible to achieve the planned level of winter wheat yield of 5.37-5.95 t/ha. The combined effect of nitrogen fertilizers and plant protection chemicals allows a differentiated approach to the role assessment of each studied factor de-pending on weather conditions. It has been revealed that the optimal combination of the applied means of chemicalization in the crop rotation system ensures the implementation of the planned level of grain yield of winter wheat in the range from 5.37 to 5.95 t/ha.