Assessment of the Effect of Sunflower Agrocenosis on the Characteristics of the Structural and Aggregate Composition of Typical Black Soil

The research was conducted on the Bila Tserkva National Agrarian University experimental field on a typical deep, low-humus chernozem. The methods of main cultivation in the sunflower agrocenosis of grain-row crop rotation had a major influence on the soil structuring processes. The use of moldboard and no-moldboard tillage increased the number of the most agronomically beneficial aggregates (0.25-10 mm) in the 0-10 cm soil's layer at the beginning of the sunflower growing season by 6.0% compared to shallow no-moldboardof tillage the soil. By the end of the growing season in the sunflower agrocenosis in the 0-30 cm soil layer, compared to the beginning of the crop growing season, the number of agronomically beneficial aggregates (0.25-10 mm) decreased, the number of fractions larger than 10 mm and fractions smaller than 0.25 mm increased. The coefficient of structure for moldboard and no-moldboard tillage significantly increased compared to shallow no-moldboardof tillage. The use of shallow no-moldboardof tillage and moldboard with no-moldboardof tillage was led to an increase in the content of stable aggregates by 1.2-7.5%. The highest yield of sunflower was recorded for the use of moldboard with no-mold-boardof tillage - 2.72 t/ha, which is significantly higher than other variants. The use of shallow no-moldboardof tillage for 10-12 cm with disc tools led to a notable decrease in productivity compared to the control. Improving the water resistance of soil aggregates during moldboard and no-moldboard tillage and shallow no-moldboardof tillage helps to preserve the soil's potential fertility.