Payment for fertilizers by productivity of rotation crops as an indicator of their application efficiency

This article analyzes the yield and protein grain productivity in the eight-field crop rotation system, developed in space and time. The yield and chemical composition of the primary and secondary crop products have been studied without fertilizers, with the background of phosphorus-potassium fertilizers, and with complete calculated fertilization systems - two mineral and one organomineral ones. The experiment has been of a two-factorial design; in addition to varying fertilizer doses, the effects of microbiological preparations on annual grasses and winter rye has also been studied. It has been established, that the yield of the vetch-oat-mustard mixture increases significantly when using complete calculated fertilizer doses compared to the control, by 6-6,3 t/ ha. The biological preparations provide a slight increase in the green mass yield, averaging 5%. All studied fertilizer doses provide increased winter rye grain yield. The highest increase of 1.7 t/ha without the preparation and 1.9 t/ha with the preparation has been achieved in the variants with the calculated fertilization system of the crop and a high dose of nitrogen fertilizers. The three-year long experiment has shown that the cost of 1 kg of active fertilizer substance has amounted to 33.3–47.6 kg of green mass of the vetch-oat-mustard mixture without preparation treatment and to 4.53 - 8.15 kg of winter rye grain (exceeding the standard by 1.3 - 2.4 times). When increasing the applied fertilizer doses by more than two times, the cost has been decreasing slightly. The application of microbiological preparations has increased the cost of fertilizers by 8-28% on annual grasses and by 26-65% on winter rye.