10 research outputs found

    Patterns of Influence of Winter Wheat Sowing Density on Its Yield

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    Introduction. The article deals with the soil morphological features and grain varietal characteristics as the main factors on which the dynamics of the winter wheat development from seedlings to full grain ripeness depends. Aim of the Article. The article is aimed at determining the main patterns of plant development depending on internal and external factors affecting the winter wheat yield. Materials and Methods. The winter wheat variety RS-1 “Tanyaˮ was an object of the research. Sowing was carried out in the production zones of the North Caucasus Federal District. The size of the area amounted to 70 ha; there were two experiments with different seeding rates. The reliability of the results was checked using Fisher's and Student's coefficient. There were carried out monitoring of the complete cycle of plant development - from seedlings to full grain ripeness. Results. The dynamics of changes in morphological parameters of plants germinated from seeds at seeding rates of 2.6 and 6.5 million pieces/ha was compared. The role of external and internal factors determining the dependence of wheat yield on seeding rate was analyzed. The external factors included the growth environment factors determining the health of plants and relating growth environment to the sowing density. At the same time, there were considered physico-chemical properties of soil including its fertility with capacity index (the amount of mineral substances and their fractional composition), the strength of the bond between mineral substances and the matrix soil, and the rate of transition of soil ions from the matrix soil to aqueous solution. When analyzing the soil prepared by the proposed cultivation technology, it was found that at a seeding rate of 6.5 million pieces/ha the number of productive stems was 550 pieces (0.0575 pieces/kg of stems), and at a seeding rate of 2.6 million pieces/ha their number was 575 pieces (0.183 pieces/kg of stems). Discussion and Conclusion. The influence of wheat seed sowing density on yield was evaluated using the Gardner equation and parameters of sorption properties of wheat root systems. It was shown that for wheat sowing density at seeding rates of 2.6 and 6.5 million pieces/ha the ratio between the values of diffusion coefficients D(6.5)/D(2.6), obtained taking into account the grown stems, was ~ 1.7 times. It was found that the determining factor is the soil structure, on which the parameters of water supply depend. The type of developing root system is determined by the water absorption rate and the depth to which water is extracted from the soil per plant. The factors determining the effect of seeding density on yield include osmotic parameters of seed cell membranes. Accumulation of proline as an osmotically active organic matter in the cell promotes water retention in the cell. The use of microelements and growth regulators for treating seeds germinated at sowing rates of 2.6 and 6.5 million pieces/ha leads to a greater increase in the proline concentration in the cytoplasm in the first case than in the second

    Ten millennia of hepatitis B virus evolution

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    Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between ~10,500 and ~400 years ago. We date the most recent common ancestor of all HBV lineages to between ~20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for ~4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic

    Results of tests of devices for sunflower harvesting in economic conditions

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    The results of tests of devices for sunflower harvesting differing in design, the number of rows to be removed, the presence of the chopper stems in real economic conditions and machine testing stations

    Modern approaches to technology of cultivation of corn

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    Nowadays, corn is an important source of nutrients in the human diet, as well as a valuable energy feed with the highest digestibility among cereals, a valuable raw material for the food, medical, microbiological, chemical industry and other sectors of the national economy. Increasing of corn grain production is one of the most important conditions for stabilizing the Russian food base. Being one of the technological crops that is demanding to growing conditions, corn is the most productive forage crop. It is important to note that the yield of corn depends not only on the fertility of the soil, but also on the methods of its processing and cultivation. One of the reasons holding back the growth of corn grain production is the high contamination of crops. In this paper, the influence of various cultivation technologies and methods of caring for maize crops on productivity is studied. It is shown that the highest yield and effective protection from weeds is obtained with an optimal combination of chemical and mechanical methods of crop care

    Substantiation of the parameters of a typical seed-growing farms of the republic of kazakhstan on the basis of digitalization of seed production

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    In general, the state of seed production in Kazakhstan can be characterized by the following figures. According to Kostanay branch of Kazakh research Institute of mechanization and electrification of agriculture total requirement of seeds is around 2 million tons. These farms provide 70% of the Republic'sfarms with seeds, the remaining 30% are imported from Russia. The studies have shown that all grain-producing regions of Kazakhstan can be classified into three categories according to the annual gross grain harvest, respectively, 16; 15; 3.26 and 2.9 million tons. It is advisable that typical seed farms have the following characteristics: in the first category of regions — the average area of one farm — 2.8 thousand hectares, the average annual grain harvest — 8.06 thousand tons, agro term — 10 days, the required total seed collection -1.78 million tons for all seed farms in the amount of 220 units. Accordingly, in the second category of regions — 1100 hectares; 2.82 thousand tons; 9.5 days 360 thousand tons and 128 units. In a third category — 322 hectares of 1.02 million tons, or 9.1 days, 320 thousand tons and 312 units. Total number of typical specialized farms should be approximately 660 units

    Combined Surface Heating by Laser Beam and Subsonic Nitrogen Plasma Jet

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    The paper describes new combined heating capability of the IPMech RAS inductively coupled plasma facility VGU-4. A 200 W ytterbium laser was added to the facility as a source of radiative heating. The cylindrical specimen made of the Buran orbital vehicle’s heat-shielding tile material with a black low catalytic coating was exposed to subsonic pure nitrogen plasma jet and laser radiation. The specimen surface temperature reached 1325 ∘C during combined radiative and convective heating. The maximum heat flux obtained in the combined mode for a laser incident power of 47 W and a VGU-4 HF-generator anode power of 22 kW was 32.1 W/cm2. The convective heat flux from the nitrogen plasma jet at the same anode power was 12.6 W/cm2. Adding a laser to an existing inductively coupled plasma facility gives the future opportunity to better simulate entry into the atmospheres of Mars, Venus, the outer planets and their moons

    Simulation of the dynamic processes of a low-capacity combine harvester movement

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    To automate the process of harvesting crops, different types of harvesting machines are required. The most common type of machines used to automate ingathering are harvesters. The use of harvesters for collecting grain crops is rational in fields from 2 hectares. On smaller areas it is not profitable and difficult to apply. For applications in small areas, low-capacity harvesters with a throughput of the thresher up to 1 kg/s (small-sized) may be suitable. The purpose of this study is to analyze the cushioning mass control system of a low-capacity unmanned combine harvester using computer simulation, as well as the simulation of directional stability and turning. To calculate vertical vibrations in the Matlab/Simulink software package, a model of a cushioning system for a wheeled agricultural combine was prepared. In the same software package, simulation of directional stability and turning implementation was carried out. The parameters of vibration displacement, vibration velocity and acceleration, as well as the vibration frequency indicators on the operator's seat are determined. Comparison of the simulation results of the initial and corrected direction of movement of the harvester showed that for this model the maximum deviation from the planned path is a maximum of 10%, which is within acceptable limits. The maximum deviation of the harvester from the course does not exceed the permissible values, which is acceptable accuracy to ensure directional stability

    Gas Emissions From Volcanoes of the Kuril Island Arc (NW Pacific): Geochemistry and Fluxes

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    The Kuril Island arc extending for about 1,200 km from Kamchatka Peninsula to Hokkaido Island is a typical active subduction zone with ∼40 historically active subaerial volcanoes, some of which are persistently degassing. Seven Kurilian volcanoes (Ebeko, Sinarka, Kuntomintar, Chirinkotan, Pallas, Berg, and Kudryavy) on six islands (Paramushir, Shiashkotan, Chirinkotan, Ketoy, Urup, and Iturup) emit into the atmosphere > 90% of the total fumarolic gas of the arc. During the field campaigns in 2015–2017 direct sampling of fumaroles, MultiGas measurements of the fumarolic plumes and DOAS remote determinations of the SO2 flux were conducted on these volcanoes. Maximal temperatures of the fumaroles in 2015–2016 were 510°C (Ebeko), 440°C (Sinarka), 260°C (Kuntomintar), 720°C (Pallas), and 820°C (Kudryavy). The total SO2 flux (in metric tons per day) from fumarolic fields of the studied volcanoes was measured as ∼1,800 ± 300 t/d, and the CO2 flux is estimated as 1,250 ± 400 t/d. Geochemical characteristics of the sampled gases include δD and δ18O of fumarolic condensates, δ13C of CO2, δ34S of the total sulfur, ratios 3He/4He and 40Ar/36Ar, concentrations of the major gas species, and trace elements in the volcanic gas condensates. The mole ratios C/S are generally 7RA (where RA is the atmospheric 3He/4He). The highest 3He/4He ratios of 8.3RA were measured in fumaroles of the Pallas volcano (Ketoy Island) in the middle of the arc
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