SOFT WINTER WHEAT YIELD GROWN ON LEACHED CHERNOZEM OF THE WESTERN CISCAUCASIAN REGION

The article presents the results of a study in the agrocenosis of soft winter wheat to determine the effects of pre-sowing and early spring application of various forms and combinations of nitrogen, phosphorus, and potash fertilizers when growing it in the leached chernozem of the Western Ciscaucasia. The soil is characteristic of a satisfactory state of the structure, density: 1.26-1.42 g/cm3; active acidity (pH): 6.29- 6.58 pH; exchangeable (pH): 5.11-5.25 units; hydrolytic: 1.94-3.05 meq/100 g; the amount of absorbed bases: 27.5-31.2 meq/100 g; cation exchange capacity: 30.6- 33.1 meq. /100 g; the soil saturation degree with bases: 90.2%-94.3%; and humus content: 2.93%. Fertilizers improve the nutrient regime of the soil. The average supply level with mineral nitrogen, high and mobile phosphorus, and very high mobile potassium has been well-defined. It could lead to an increase in grain when applying N120P30K60 - 1.28 t/ha (or 24.1%), N120P90K20 - 1.47 t/ha (or 27.8%), and N120P90K60 - 1.53 t/ha (or 28.8%). The grain yield of soft winter wheat was 6.58, 6.77, and 6.83 t/ha, respectively. The protein content in the grain varied from 13.2% to 14.3%. The collection of protein per hectare was 870.5, 948.5, and 958.3 kg/ha for the treatments N120P30K60, N120P90K20, and N120P90K60, respectively. The protein in the control was equal to 554.9 kg/ha. Dispersion analysis of the study results showed the share of the contribution of the factor "combination of fertilizers" was 75.95%. Similarly, the data analysis of the conditions of the agricultural year and combinations of mineral fertilizers has a smaller share - 19.24%. With the introduction of N120P30K60 and N120P90K20, the payback of mineral fertilizers by increasing the yield of soft winter wheat grain is the largest - 6.10 and 6.39 kg/kg a.i. NPK, respectively.