No abstract

The article presents the results of studies of complex effect of biopreparations use during basic and pre-sowing soil tillage on root rot damage and leaf and stem infections of spring grain crops (wheat cv. Svecha, barley cv. Lel’, oats cv. Selma). Studies of 2010-2017 were carried out in seven-field crop rotation on sod-podzolic medium-loam soil. The root rot damage of spring wheat was significantly lower (17.9 %) by surface tillage than by ploughing (22.5 %) in arid conditions with insufficient productive moisture (9.1-17.2 mm) and an increase in soil density (1.37-1.43 g/cm3). Under optimal humidification conditions, the differences in root rot damage of barley are equaled (21.3 and 22.4 %). High soil density (1.32-1.36 g/cm3) also caused an increase in the number of diseased oat plants by surface tillage (21.6) compared to ploughing (14.6 %). Treatment of crops with the preparations Streptomyces castelarensis А4 and Pseudobacterin-2 in the tillering phase led to a significant decrease in root rot damage only on oats (by 17.1 and 17.4 %, respectively). The degree of damage of spring grain crops with leaf and stem diseases was not significantly affected by the methods of basic and pre-sowing tillage. Only the use of a combined sowing unit for cultivation of spring wheat reduced the damage with leaf rust by 2.9 %, with septoriosis – by 1.0% compared to the control. On wheat, the preparations were effective on the background of ploughing reducing leaf rust damage by 15.2 and 11.6 %. The preparation S. castelarensis А4 had a greater effect on barley: the number of plants affected by crown rust was 19.1% less. Pseudobacterin-2 had a better effect on the background of surface tillage, reducing the incidence by 12.9 % relative to the control (ploughing to 20-22 cm). On oat sowings, the preparations were comparable in effect: the intensity of crown rust damage was significantly lower by 5.0 and 4.7 % compared to the control. The action of S. castelarensis А4 is more effective on the background of surface soil tillage. Pseudobacterin-2 had the best effect by plowing. The damage of wheat with stem rust and septoriosis was low. Thus, the methods of basic tillage did not affect the damage of grain crops with leaf and stem diseases and significantly decreased the development of root rot in wheat and oats. Methods of pre-sowing tillage did not have a significant effect on the damage of spring grain crops with root rot and significantly reduced the damage of wheat with leaf rust and septoriosis. The preparations used reduced the intensity and the development of root rot of oats and leaf and stem diseases of wheat, barley, oats.

The studies were carried out in the Kirov region on sod-podzolic sandy loam soil in a long-time stationary experiment established in 1976. The article provides data (2010-2017) on four fallow-grain-grass crop rotations with various types of fallows, annual and perennial legumes (25-50 %), intercrops (12.5-37.5 %). The purpose of the studies is to compare the influence of some biologization techniques in eight-field crop rotations on the change in soil fertility and the balance of nutritional elements of sod-podzolic sandy loam soil. It is found that the application of low doses of mineral fertilizers (N30P30K30) and various types of green manure crops per rotation has significantly increased the content of mobile phosphorus in the arable soil layer (by 39-46 mg/kg). According to grouping the provision of soils with phosphorus, the content of this element passed into the «high provision» group. The content of exchangeable potassium in the soil remained in the «increased» provision group. In the control crop rotation with clean fallow at a minimum supply of nutrients with mineral fertilizers and root-stubble residues, the balance of nitrogen, phosphorus and potassium was created negative at the intensity of less than 100 %. The replacement of clean fallow for cropped and green manure fallows, as well as the introduction of intermediate cruciferous crops into the crop rotation structure contributed to the positive balance of nitrogen (250.2-484.3 kg/ha) with the intensity of 124-150 %. The biologization factors used in crop rotations favored the creation of a positive phosphorus balance (12.5-148.1 kg/ha) with the optimal intensity of 117-163 % and a positive potassium balance (128.9-395.8 kg/ha) with the intensity above the optimal value of 116-148 %. The most advantageous in terms of productivity and ensuring a positive balance of nutritional elements is crop rotation with two green manure fallows and sowing of stubble and hay cruciferous crops in three fields.

The article presents the results of a long-term stationary three-factor experiment on sod-podzolic loamy soil to identify the effectiveness of various methods of basic and pre-sowing treatment of soil, the use of biological preparations in the technology of cultivating grain crops in six-field crop rotation. It was established that the most profitable elements of the technology in energy and economic terms will be: surface-cut treatment with KPS-4 cultivator and introduction of Azotovit and Phosphatovit biologics into the tillering stage of oat in a vetch-oat mixture for green feed; surface-cut treatment with KBM-4,2 cultivator or with pre-sowing treatment with a APPN-2,1 combined aggregate and introduction of Azotovite and Phosphatovite biological preparations into the soil before sowing winter rye for grain; ploughing with pre-sowing treatment with APPN-2,1 combined aggregate for spring wheat; surface-cut treatment with pre-sowing treatment with APPN-2,1 combined aggregate and introduction of biologic preparation based on strain Streptomyces hygroscopicus A4 at tillering stage of oat in pea-oat mixture for grain-hay; ploughing with KPS-4 cultivator and introduction of Pseudobacterin-2 biopreparation at barley tillering stage; ploughing with pre-sowing treatment with APPN-2,1 combined aggregate and introduction of biologic preparation based on strain Streptomyces hygroscopicus A4 at oat tillering stage.