Wind resistance of southern carbonate and ordinary сhernozems in agroforest landscapes of the steppe zone of Russia

Relevance. The rate of destruction of chernozems in the steppe zone as a result of deflation is very high. There is a threat of their loss of the humus horizon. To optimize the complex of protective measures, it is necessary to establish the regularities of the formation of wind resistance of these soils.Methods. The seasonal dynamics of the structure of the upper layer (0–5 cm) of chernozems of the steppe zone of the Lower Volga region and the Central Pre-Caucasus in the network of forest belts is studied. The aggregate composition was determined by fractionation of an air dry sample. The wind resistance of the soil was assessed by the total content of particles with a diameter of less than 1 mm.Results. It has been established that the open surface of southern carbonate chernozems is deflationary dangerous at any time of the year. Two spraying peaks were revealed — in early spring and before harvesting grain crops. In the first period, the content of particles with a diameter of less than 1 mm was 33–47%, in the second — 60–61%. Shelter forest belts reduced soil spraying in the zone of effective influence. A change in the internal structure of the deflationally dangerous fraction was detected during the year. The disintegration of large aggregates and an increase in the volume of smaller ones were observed. By the harvesting period, the number of particles with a diameter of 0.5–1.0 mm decreased by 1.7–2.6 times compared to the spring. Number of aggregates with a diameter of 0.1–0.5 mm, most strongly blown by the wind, increased by 1.3–1.8 times. The total dispersion of ordinary chernozem is almost two times lower than that of southern chernozem. However, the amount of particles with a diameter of 0.1–0.5 mm in the deflationary dangerous fraction of southern carbonate chernozem in the spring period is 37%, during the harvesting period — 50–56%. And in ordinary chernozem, already since the spring, there are more than 55% of such particles, in the future their number increases to 60%. As a result, by the harvesting period, the danger of a fraction with a diameter of less than 1 mm becomes the same for both subtypes of chernozems. This requires adjusting the complex of protective measures.

Analysis of Bacillus thuringiensis treatment impact on microflora and cellulosolytic processes in southern chernozem

When using insecticides based on B. thuringiensis in biocenoses, the issues of their influence directly on plants and soil fertility are particularly relevant. The aim of the research was to study the direction of microbiological processes in the soil after processing potato plants with liquid spore cultures of entomopathogenic B. thuringiensis 792, 800, 810, 815, 857, 888, 902, 989, 994 and 0371 strains. The nature and extent of insecticide exposure were assessed by the quantity of microorganisms in the main ecological and trophic groups. It has been shown that soil treatment with B. thuringiensis strains 792, 854 and 989 influences the intensity of southern chernozem CO2 emission most actively, by 5.7-6.0 times. The studies made it possible to establish that B. thuringiensis strains 810, 854, 888 and 902 are able to exert the most active effect on the decomposition of cellulolose, increasing its activity by 93.7; 85.6; 82.0-93.7% to control. The statistically significant relationships study of correlation dependences made it possible to conclude that the treatment of southern chernozem with strains of B. thuringiensis 792, 800, 810, 854, 888 and 0371 does not have a destructive effect on soil microbocenosis.

Taxonomic structure of the southern chernozem under application of biological preparations and different farming systems

The study of the taxonomic structure of the southern chernozem under influence of microbial preparations and various farming systems in the conditions of the southern steppe zone has been carried out. Metagenomic analysis of the microbiome of southern chernozem showed the presence of 174 genera representatives of prokaryotes, among which 17 are dominant, representing more than 1%. Farming systems cause changes in the taxonomic structure of the microbiome in comparison with virgin soil in the steppe zone. The influence of microbial preparations of complex action on the qualitative and quantitative composition of the microbiome of southern chernozem and increasing under no-till farming system has been established. The maximum content of water-soluble organic matter was found in virgin soil, which has higher amount of plant residues, up to 491 mg/kg of soil. Under the influence of farming systems its amount decreased in 4.2-8.5 times. The use of a complex of microbial preparations in the southern chernozem contributed to an increase in the amount of water-soluble fraction of humus depending on the farming system: 1.7 times with the conventional farming system and 3 times with no-till compared to the control without CMP.

The Importance Of The Variety Of Spring Hard Wheat In The Formation Of Yield And Quality Of Grain In The Southern Chernozem Of The Orenburg Region

Wheat is a plastic crop and therefore occupies a huge area, spreading in the north to the cold pole (Verkhoyansk), and in the south to the border of cultivation of cultivated plants. In some regions of Azerbaijan, it is sown in fields below sea level, and in Peru, it rises in the mountains up to 4000 m. Cultivation of wheat on a huge territory is possible due to the high adaptive properties of the culture, its resistance to frost and drought. Almost half of the bread composition is represented by carbohydrates, in which starch takes the main place (up to 80%). Under the influence of enzymes, it is broken down to simple sugars that the body needs. The total digestibility of bread carbohydrates reaches 90-92%. The protein substances of bread are of the utmost importance, thanks to which a third of a person’s daily needs are often covered in our diet. Bread is the main source of supply for the body with vitamins B1, B2, PP. It is rich in phosphorus, potassium, magnesium, sulfur.

Influence of long-term use of various doses of mineral fertilizers on the productivity of grain-fallow crop rotation in the arid steppe of the Volga region

The work reflects the analysis of changes in the productivity of crops of crop rotation during the long-term use of fertilizer systems in a stationary experiment for the period from VI to VIII rotation (1999-2001 - 2016-2018). The influence of various doses of nitrogen, phosphorus and nitrogen-phosphorus fertilizers on the change in the content of nitrate nitrogen and mobile phosphorus in the conditions of the southern chernozem for the specified period of research was determined. The responsiveness of crop rotation crops to the application of nitrogen, phosphorus, and nitrogen-phosphorus fertilizers in minimum, medium and high doses has been established.

Regularities of the Growth of Pedunculate Oak (QUERCUS ROBUR L., 1753) in the Protective Plantings of the Steppe and Forest-steppe of the Volga Upland

The purpose of the study is to establish the regularities of the growth of pedunculate Oak in protective forest stands on erosion-prone slopes in the conditions of the steppe and forest-steppe of the Volga Upland. Studies have established a regular decrease in the height of the petiolate oak on the southern chernozem and gray forest soil by 6.9-11.3% with an increase in the slope of the slope by 2 times, which is associated with a drop in soil fertility as a result of increased erosion. The index of oak growth intensity with an increase in the slope slope increases on both types of soils by 21.4-38.5%, and the productivity of cambium decreases by 14.1-23.6%. The same trends in the dynamics of taxation indicators are characteristic of the accompanying species of petiolate oak-holly maple and small-leaved linden. The coefficients of determination of the relationship of growth in the height of the pedunculate oak from the indicator of growth intensity and productivity of cambium are 0.95-0.98, which indicates a close interdependence.

MODERNIZATION OF ELEMENTS OF STRIP-TILL TECHNOLOGY UNDER A SUNFLOWER IN THE CENTRAL PRECAUCASIA ZONE

The need to introduce new progressive technologies for sunflower cultivation in Stavropol Territory is based on an analysis of trends in the development of arable land for this crop over the last ten-year period from 2010 to 2020. A significant annual increase in the areas under sunflower in the arid zone by an average of 3.9 thousand hectares and a tendency for this indicator to increase in zones of unstable and sufficient moisture by 0.55 and 1.0 thousand hectares have been established. The purpose of the research is to evaluate the effectiveness of the modernized soil cultivation system in the Strip-till technology for sunflower in the unstable moisture zone of the Stavropol Territory on the southern chernozem, poorly humified in comparison with the traditionally adopted cultivation system. A distinctive feature of the new strip-till soil cultivation system is continuous disc stubble cultivation with the Catros harrow 8 - 10 cm instead of leaving untreated stubble strips. In the process of research, using the method of the theory of dimensions, an inverse power-law dependence was derived, showing that the smaller the weighted average diameter of the aggregates D, the higher the soil density P, taking into account the correction factor C for a certain type of soil. It was found that under relatively favorable moisture conditions in 2019 and in the dry season of 2020, spring moisture accumulation under strip-till was higher than under traditional ones by 12 and 8 mm, respectively. Cultivation of sunflower, with preliminary disc processing of stubble and the formation of strips with slots for sowing crops, following the Strip-till technology, is more effective in comparison with the traditionally adopted technology in the southeast of the Stavropol Territory, since an average increase in sunflower yields over the years by 0.20 t/ha with a higher profitability of 31%

Application of Organomineral Fertilizers to Winter Wheat in the Rostov Region

Modern crop cultivation technologies are based on various methods of seed and plant treatment using environmentally friendly drugs that stimulate growth and the development of the plants, and increase their productivity and stress resistance. It has been established that the use of organic fertilizers positively affects the vital signs, yield and grain quality of cereal plants. When cultivating winter wheat on the southern chernozem of the Kamensky district (in the Rostov region), the organic fertilizers Router (0.5 or 0.25 l / ton) and Leyli (0.25 l / ton) were used for seed treatment, and Soft Guard (0.2 l / ha) and Humiful Pro (0.2 l / ha) were used in spring tillering and in the flag leaf phase against the background of mineral nitrogen fertilizers in a dose of N32P32K32; the frozen-thawed soil was fertilized with ammonium nitrate in a dose of N40 and foliar fertilization was conducted with carbamide in the heading phase using a dose of N20. This increased the average grain yield by 64.2-64.8% compared with the control variant and by 31.4-32.4% compared with the use of mineral fertilizers. The maximum yield gain was achieved by using the soft-root organic fertilizers Soft Guard (0.2 l / ha) and Gumiful Pro (0.2 l / ha) against the background of mineral fertilizers and seed treatments with Router (0.5 l / ton). Keywords: winter wheat, southern chernozem, organic fertilizers