The review presents the perspectives of using DNA-markers in barley breeding for resistance to toxicity of aluminum, boron, manganese and cadmium ions. Currently, there have been identified quite a number of ion-resistance genes and quantitative trait loci (QTLs). Markers 1 kb-insertion and HvMATE-21indel that are linked to the HvAACT1 gene are recognized as standard gene-specific markers of aluminum resistance. Loci QTLs still require validation, but in the future they can serve as a basis for pyramiding several loci of aluminum tolerance in a single genotype. Molecular markers specific to the boron resistance genes of barley (HvBot1, HvNIP2;1 and HvBot2), and the QTL of barley resistance to the manganese toxicity (QSur.yf.3H) have also been developed. QTLs, genes, and markers related to low cadmium accumulation were identified in barley. Most studies focus on finding and developing markers linked to ion resistance rather than on their practical application in plant selection. However, breeding programs have already used markers related to the resistance of barley to high concentrations of aluminium and boron ions. Marker-assisted selection has high potential, and in course of time advances in science make its technologies more accessible, easier, and less expensive.

In 2013-2019 in the conditions of Kirov region 178 varieties of spring soft wheat from the collection of the Federal Research Center of N.I.Vavilov All-Russian Institute of Plant Genetic Resources (VIR) were studied according to loose smut resistance, plasticity and yield stability. Among studied varieties 36 immune and 12 practically immune to loose smut infestation samples have been revealed. They can be used as sources of resistance in selection. The most favourable conditions for infestation of spring soft wheat plants with loose smut develop since the beginning of blossoming till grain filling. The higher the air temperature and the amount of precipitation during this period, the higher is the percentage of wheat plants affected with this disease. As the percentage of the stems affected by loose smut increased, total yield losses grew as well (r = 0.99). Nineteen varieties of spring wheat significantly exceeded the standard variety Bazhenka (Russia) in yield on an infection background. Five mid-susceptible varieties which showed tolerance to the disease have been selected. They are Tulaykovskaya Nadezhda (Russia), Samgau, Dostyk, Karabalykskaya 91 (Kazakhstan) and Visa (Belarus). During the years the following varieties revealed the highest and stable productivity: Stepnaya 50, Dostyk (Kazakhstan), Kazanskaya Yubileynaya, Niva 2, Provincia, Egisar 29, Sudarushka, Tulaykovskaya Nadezhda (Russia), Hoffman (Canada), UL Pettit (USA) and Leguan (Czechoslovakia). The following varieties were designated as the intensive type: Tyumenskaya 26, Elizaveta, Maria 1, Melodiya, Niva 2 (Russia), Kharkovskaya 10 (Ukraine), Samgau (Kazakhstan), Visa (Belarus), and American varieties Ranger and UL Pettit (b _i > 1). Varieties Ranger and UL Pettit showed high productivity in favorable cultivation conditions. Varieties Mazhor (Ukraine), Favorit (Russia) and Karabalykskaya 91(Kazakhstan) (b_i<1) should be used on an extensive background. By deterioration of cultivation conditions the productivity of these varieties decreased insignificantly. The relationship between productivity and adaptability parameters has been established (b_i , Ноm). The highyielding varieties have been characterized as more plastic (r = 0.69) and stress resistant (r = 0.73).

The experimental studies were carried out in the Rostov region of Russia in 2019. Three variants of grinded wheat grain mixed with biomass of black soldier fly larvae with raw animal material content of 10, 12.5 and 15 % by mass were extruded at varying temperature. The content of amino acids in raw material and finished extrudate was determined. It has been established that the feed mixture containing grinded wheat grain and biomass of black soldier fly larvae can be successfully extruded at the temperature of 121-135 ºC. As the extrusion temperature rises in the range of 115º-140 ºС, the content of amino acids in a finished extrudate decreases. Change in larvae content in the feed mixture does not affect the nature of the correlation between the amino acids content in the extrudate and the extrusion temperature and process behavior. It has been found that with increasing temperature the amino acids content in the extruded feed decreases with an accelerated velocity irrespective of the insect biomass content. The rational temperature range for extrusion of feed mixture containing grinded wheat grain and larvae biomass was determined within 121-127 ºC. This range provides no more than 30 % decrease in indispensable amino acids content in the extrudate. The extruded feed containing 15% of insect larvae biomass contains 9.6±0.13 % of amino acids, including 4.38±2.01 % of indispensable amino acids. Extrusion of larvae biomass mixed with grain of cereal crops is considered to be a promising direction for improving production of feed for fish and farm animals.

The article presents the results of the influence of various aerating agents, carriers of new generation oil-oxidizing biological product on the agrophysical parameters of sod-podzolic soil highly contaminated with oil (up to 10%), and on the rate of oil decomposition in it. The studies were carried out in a microfield experiment in the conditions of the Udmurt Republic. It was established that during the growing season of 2019 all studied carriers of the biological product had positive effect on these indicators, however, the parameters of the changes were determined by their types. Thus, the application of sawdust, barley straw and flax shive into the soil provided an increase in the structural coefficient by 0.83-0.99 units or 35-43 %. All studied carriers of the biological product statistically significantly reduced the density of the contaminated soil, the greatest effect on this indicator was exerted by flax shive (by 0.42 g/cm³ or 32 %) and sawdust (by 0.34 g/cm³ or by 26 %). The application of vermiculite increased the productive moisture content in the contaminated soil most significantly - by 115 m³ /ha or by 50.7 %. The improvement of agrophysical properties of oil-contaminated soil by carriers of the biological product increased drastically the effectiveness of the preparation for oil decomposition. The greatest effect on this indicator (by 9.9-10.9 mg/kg or 40.2- 44.3 %) was exerted by the biological product in combination with flax shive, lignin and straw. The application of organomineral fertilizers into the contaminated soil also improved the agrophysical properties of oil-contaminated soils significantly and reduced the residual oil content in it by 13.0 mg/kg or 52.8 %.

The article presents the design of a rod elevator with an adjustable inclination angle of the apron, which reduces damage to marketable products of root crops and bulbs with maximum separation. The results of theoretical studies of a rod elevator on substantiation of the structural and technological parameters during its interaction with a heap of onion sets are presented. The constructive-technological scheme of the separating rod elevator with an adjustable inclination angle of the apron which improves the quality indicators of harvesting onion sets is substantiated and developed. It has been established that with increasing angle of the longitudinal inclination of the apron, the relative speed of movement of the heap of onion sets decreases. In the absence of air flow, the relative velocity of the onion set heap with a longitudinal change in the inclination of the rod elevator apron in the considered range varies from 0.34 to 0.47 m / s. Changing the angle of the longitudinal inclination of the rod elevator by 5º significantly changes the relative average speed of movement of the heap of onion sets. A mathematical model of the movement of a heap of onion sets along the surface of the rod elevator with a change in the direction of its oscillations in the horizontal plane is developed

The article presents the comparison testing of particle trajectories in the pneumatic separation channel (PSC) of the pneumatic seed separator SP-2F and its bend, calculated using computer simulation method and two experimental-theoretical methods. They are based on taking into account the real airflow velocity field. In the first variant, the velocity field was measured in an idle mode, in the second at the nominal grain load. The studies were carried out in a vertical PSC with a supporting grid divided into two parts by a partition wall. In the variant with the theoretical velocity field the trajectories of light and grain impurities in the first part of the PSC are shifted closer to the outer wall. In the second part of the channel, particles with hovering speed of 8.0...10.0 m/s are carried upwards, and with hovering speed of 11.0 m/s they fall down into the purified material. In the variant of the experiment in an idle mode, particles with the hovering speed of 7.0...10.0 m/s rise up in the second part of the PSC. In the variant with grain load, particles with the hovering speed of 7.0...9.0 m/s rise upward and ricochet off the inner walls of the PSC and a bend wall, and particles with the hovering speed of more than 10.0 m/s fall down into the purified material. In the variant of the experiment with the grain load, the particle velocity with the hovering speed of 5.0...9.0 m/s at the exit of the PSC bend is more evened as compared to other options - 2.3...2.7 m/s, and the velocity vector of most particles is directed at a lower angle to the horizontal: from 4 up from the horizontal to 17 down from the horizontal. The most accurate is the calculation of particle trajectories using the velocity field in the PSC at the nominal grain load. The results of the study can be useful in the theoretical substantiation of the design parameters of pneumatic systems of grain cleaning machines.

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Communication to article N. K. Mazitov, R. L. Sakhapov, Y. Kh. Shogenov et al. «Competitive complex of machinery and technologies for the production of grain and feed».

The development of tractor design is closely related to its technological updating, improving environmental performance and increasing usability. Study of this problem in a historical context shows the unity in approaches of various agricultural tractor manufacturers to tractor design aimed at increased productivity and reduced operation costs in accordance with the requirements for agronomic and environmental performance. The main task of the first-generation tractors was to develop traction for agricultural work with maximum productivity and cost-effectiveness. Solution of these problems required further development of the tractor theory and the idea of the processes quality, and ensured the optimization of design and performance. As a result, the designs of tractors from different manufacturers developed in the same direction. Modern tractors are equipped with electronically controlled turbocharged diesel engines and have systems reducing toxicity of the exhaust gases. Power transmission of the tractors is implemented either with a robotic gearbox without interrupting the power flow, or in a continuously variable format, which ensures a more optimized operating mode. While for small-traction-class tractors stepless power transmission is provided with a mechanical variable speed gear, the rest of the tractors require electronicallycontrolled hydromechanical transmissions. As the capacity of power stations grows and an extensive power grid based on renewable energy resources is developed, the demand for electric tractors is to be increased. Tractors with hybrid power plants are likely to be produced at the transitional stage of development. They have the advantages of controlling processes in the machine and tools, the ability to provide agricultural implements with electric power for carrying out their work processes and ensuring their active drive to develop traction as well.

A variety of topography, climate, vegetation and soil of the Southern Urals indicates the need to choose the technology and complex of machines for cultivating crops in accordance with the conditions of the zone and economy. Analysis of existing crop cultivation technologies showed the need for their improvement. To ensure the possibility of changing the methods of soil cultivation and sowing depending on soil and climatic conditions, the cultivated crop and the place of culture in crop rotation, a universal technology is proposed, which provides for the need to create conditions for growth and development of plants based on accumulation and economical use of moisture with application of working bodies and a complex of tillage and sowing machines appropriate to the conditions of the zone. The types of working bodies for basic, additional and presowing tillage and sowing of agricultural crops by various methods are substantiated. The degree of universalization of combined machines for farms with different areas of arable land is established. For small farms with arable land up to 1200 ha, one universal machine with replaceable working bodies or modules is needed to perform primary, secondary and pre-sowing tillage and sowing. For medium-sized farms with arable land up to 10 thousand hectares, separate universal machines with replaceable working bodies are needed for primary tillage, with replaceable modules for additional tillage, and tillage sowing machines with replaceable modules with different types of working bodies are necessary for pre-sowing tillage and sowing. For large farms with arable land area of over 10 thousand hectares it is necessary to use combined single-purpose machines. Based on the previously conducted studies, using the obtained mathematical models and agrotechnical requirements for developing new machines, calculations were carried out and the design parameters of machine complex for tractors of 1.4...5 traction class were substantiated. They were produced by LLC Chelyabinsk Compressor Plant and Varnaagromash LLC with various degrees of universalization The complex of machines for cultivating agricultural crops developed and produced at these plants for various types of farms makes it possible to fulfil all the elements of the proposed technology adopted in the zone in accordance with the agrotechnical requirements as well as soil and climatic conditions of the zone.