AGROCHEMICAL REGULATORY INDICATORS OF MINERAL NUTRITION OF SPRING WHEAT IN THE FOREST STEPPE OF WESTERN SIBERIA

The authors studied the influence of different methods of using micronutrient fertilizers on the yield of spring wheat grain and established standard agrochemical indicators of mineral nutrition on the grassland-chernozem soil of the Omsk region. Use was made of helated micronutrient fertilizers (zinc and copper). Chelated micronutrient fertilizers are an organic complex of a microelement with a chelating agent, in which the microelement is freely absorbed by the plant. The advantages of chelated micronutrient fertilizers are an increase in the availability of trace elements, because these compounds are entirely supplied to the leaf during foliar feeding or during pre-sowing treatment of seeds, protection against the formation of insoluble, inaccessible, economical consumption. The experiment established that the use of zinc and copper chelates in the cultivation of spring wheat in the forest-steppe conditions of the Omsk region is effective. The best rate of zinc and copper for pre-sowing seed treatment is 200 g/t. For foliar top dressing in the tillering phase, the best rate of zinc chelate is 20 g/ha, the most effective top dressing is copper chelate at a rate of 10 g/ha, as it is less expensive in terms of the amount of the applied product. Optimizing spring wheat nutrition by using zinc and copper chelates by foliar feeding of plants in the phase of stemming provided an average increase in yield from 0.03 to 0.16 t/ha of grain (1.4–7.3% compared to control). Experiments revealed a positive effect of zinc chelate in this phase of the yield development, when zinc was used at a rate of 20 g/ha, the greatest yield increase was obtained 0.14 t/ha (2.20 t/ha in control), when using copper chelate the maximum yield was obtained at a rate of 20 g/ha. To obtain a ton of yield in the best version of Zn200, spring wheat required: N – 35.7 kg, P2О5 – 21.9 kg, K2О – 22.6 kg, Zn – 47.56 g, Cu – 5.91 kg. When treating Cu200, the removal of nutrients amounted to: N – 33.9 kg, P2О5 – 21.8 kg, K2О – 22.1 kg, Zn – 54.03 g, Cu – 4.80 g. When carrying out foliar top dressing in the tillering phase of Zn20, the removal of nutrients from a ton of crop yield amounted to: N – 35.4 kg, P2О5 – 23.4 kg, K2O – 23.4 kg, Zn – 49.7 g, Cu – 4.87 g; in the Cu10 variant it was required: N – 34.3 kg, P2O5 – 22.5 kg, K2O – 23.6 kg, Zn – 52.9 g, Cu – 4.36 g. Foliar dressing in the booting phase at a rate of Zn20 was characterized by the following per-ton removal: N – 34.6 kg, P2О5 – 25.3 kg, K2О – 24.9 kg, Zn – 65.0 g, Cu – 5.13 g, treatment with copper chelates Cu20, the removal of nutrients amounted to: N – 34.7 kg, P2О5 – 24.4 kg, K2O – 25.9 kg, Zn – 61.1 g, Cu – 6.4 g. The element utilization coefficients from the soil (EUC) accounted for: nitrogen – 87%, phosphorus – 8.0%, potassium – 6.0%, zinc – 7.0%, copper – 2.0%.