Mechanization and automation of working processes of tillage and seeding

A new layout of the working elements of the chisel cultivator is presented: V-shaped weeps with the chisel rippers on the end and tooth spring harrows allowing to use the chisel cultivator for primary autumn soil tillage after harvesting. With installation of the rippers in the form of the shank together with the V-shaped weeps, it is possible to carry out solid surface tillage, cut the weeds fully, loosen the lower horizon, level the surface of the tilled field, and improve the water-air regime of the soil. A new model of the cultivator tooth is created performing simultaneously cultivation of the soil layer, cutting of the weeds, and para-plowing. The structure of the chisel cultivator permits the reduction of the metal consumption by 20% as compared to the prototype without worsening the quality of the soil tillage. The pneumatic sowing machine was developed proving single-seed, combined, and bunch planting.     

Assessment of biological activity in agrogenic and natural chernozems of Kabardino-Balkaria

Parameters of biological activity (humus and microbial biomass reserves, potential intensity of the CO₂ emission, and enzyme activity) have been determined in arable and natural chernozems on the plains of Kabardino-Balkaria as a part of the system for the ecological assessment of the state of the soil cover. Integral parameters of the eco-biological state of studied soils have been calculated on the basis of obtained data, and the level of changes in their total biological activity has been determined. A statistically significant decrease of the values of all the considered biological properties under the impact of tillage has been found. The data of two-way ANOVA suggest a stronger influence of agricultural management in comparison with genetic features of chernozems at the level of subtype. Differential approach is insufficient for evaluating the total level of soil biological activity, because there are many biological properties of soil, and the degrees of their changes in agrogenic soils are different. An integral approach has been used; it integrates the obtained data into a single integral assessment parameter. In arable soils, this integral parameter decreases by 39–46% and makes it possible to assess the degree of disturbance of the ecological functions of soils and their capacity for self-restoration.     

Combined Application of Xymedon Hydrochloride with Rabies Vaccine on the Background of Immunosupression

The effect of xymedon hydrochloride on the immune response of rabbits immunized with the rabies vaccine prepared from strain Shchelkovo-51 under the influence of immunosupression induced by cyclophosphamide has been studied. Xymedon hydrochloride was injected at a dose of 5 mg kg body weight in a volume of 1 cm³ twice a day in combination with the rabies vaccine. In addition, the immune response higher level of 1: 12800 was observed in the immunosupressed animals compared to 1: 6400 in the control animals immunized without the immunostimulant. At 6 months after vaccination, the antibody concentration of 1: 93.75 ± 44.68 remaining below the protective level was recorded, which indicated the weakness of the humoral link in the immune system. The counts of T- lymphocytes, B-lymphocytes, T-helpers, and T-suppressors in the blood of the immunesuppressed rabbits immunized with the rabies vaccine in combination with xymedon hydrochloride increased 3.2-fold, 1.9-fold, 7.7-fold, and 22.0-fold, respectively, when compared with the reference values. Therefore, the protective effect was followed by increasing the antigeninduced and spontaneuous lymphocyte proliferation, the numbers of T-helper cells and T lymphocytes exhibiting the cytotoxic and suppressive activity, and the virus-specific neutralizing antibody titers in cases wherein the Shchelkovo-51 vaccine in combination with xymedon hydrochloride was administered. It should be reasonable to apply the two-step rabies vaccination with the use of the immunostimulant, in particular, xymedon hydrochloride, to ensure the adequate immune response in immunodeficient animals.     

Intensity of Respiration and Activity of Oxidizing-Reducing Soil Enzyme Depending on Their Agricultural Use

The scientifically based fertilizer system used in the 11-field grain-grass-row crop rotation promotes an increase in the lethargic respiration rate in chernozem by 20.6–22.1% and catalase activity by 21.9–27.3% with very little activity of ferric reductase. On high rice checks of meadow chernozem soils, compared to low meadow-marsh soils, the intensity of respiration increases by 18.5–22.8%, catalase activity by 15.0–28.6%, and the activity of ferric reductase decreases 21.4–41.3%. Irrespective of the agricultural use of soils, biochemical processes are more active in the 0–20 cm layer. Permanent cultivation of rice for 80 years on meadow-chernozem soil leads to a decrease in the intensity of respiration and the activity of oxidation-reduction enzymes. The ratio of the activity of ferric reductase and catalase can serve as an indicator of the oxidation-reduction state of soils and, along with iron compounds, characterize the degree of their hydromorphicity.