编号 2 (2025)

The study was conducted to compare the suitability of two mathematical methods for the procedure of forecasting the winter rye yield within abandoned lands. The training set for adjusting the forecast models (regression and neural network analyses) was the results of long-term monitoring of the winter rye yield on an agroecological transect laid within a terminal moraine hill near the city of Tver. The regression equations and perceptrons obtained for different climatic conditions, describing the dependence of rye yield on landscape conditions, were used to forecast its productivity in abandoned lands located in the same region. The developed forecasts based on regression and neural network models differ only in details. Maps of the forecast winter rye yield, created on the basis of various mathematical approaches, indicate the suitability of the studied territory for growing this crop – its forecast average weighted yield within its limits fluctuates from 1.52 to 2.61 t/ha. The optimal location for rye crops based on the map created based on the forecast results will be the landscape of the moraine-glacial plain, and areas unfavorable for growing this crop are located within the outwash plain and the Volga River valley. For the purposes of adaptive landscape farming in the Non-Black Earth Region, it is necessary to recommend the combined use of regression and neural network analysis to obtain the most reliable and informative forecasts. The creation of maps of the predicted yield of winter rye within the boundaries of an abandoned site based on the available archival data has not only a methodological but also an applied meaning, since this procedure allows us to assess its suitability for growing this crop and, thus, answer the question of the advisability of conducting expensive expeditionary research on it.

The results of a comparative study of 10 varieties of winter rye grown in a wide range of weather conditions in 2015–2024 are presented. The aim of the study was to study the ecological variation (CV), phenotypic stab_ility (PS), and ecological plasticity (BI) of four technological traits: falling number (FN), amylogram height (AH), aqueous extract viscosity (AEV), and gelatinization peak temperature (GPT). A comparative test was carried out on plots of 12 m² in a triple repetition with a seeding rate of 500 grains per 1 m². The highest grain quality was found in the GC-494hv population, which was previously screened for the high viscosity of the aqueous extract of the grain meal. On the trait FN this population was distinguished by a relatively low coefficient of ecological variation (CV = 27.7 %), had higher phenotypic stab_ility (PS = 2.5) and was characterized by increased buffering to various weather conditions (b_i = 0.81). It was shown that the traits of FN and AH varied greatly over the years, and therefore turned out to be phenotypically unstable and low-heritable (Н² = 0.20 and Н² = 0.34). The trait AEV turned out to be more environmentally stable, which is well inherited (H² = 0.64) and can serve as a reliable guideline for grain quality improvement. A negative correlation has been established between the quality characteristics and the adaptab_ility parameters CV and PS. This correlation was most strongly manifested between FN and CV (r = –0.84 ± 0.10). It is concluded that targeted selection for a high falling number will correlatively increase environmental sustainab_ility and phenotypic stab_ility of grain quality characteristics.

The study was conducted with the aim of obtaining doubled haploids with the Pi-b gene for rice Oryza sativa L. breeding. As a result of hybridization between Far Eastern varieties and the Oxy 2x sample (carrier of the Pi-b gene), 13 F₁ hybrids of six hybrid combinations were created: Sadko×Oxy 2x, Lugovoy×Oxy 2x, Darius 23×Oxy 2x, Almaz×Oxy 2x, doubled haploid (Don 4237×Dolinny)×Oxy 2x, Khankaisky 429×Oxy 2x. In vitro androgenesis technology was used to transfer the original F₂ donor plants to a constant homozygous state. 35 hybrid plants carrying the resistance allele of the Pi-b gene were preliminarily selected. 10246 rice anthers were introduced into the in vitro culture. Callus formation was observed in 25 of 35 F₂ hybrids. The highest callus formation values were noted in the hybrid plants Lugovoy×Oxy 2x – 9.33 % and Khankaisky 429×Oxy 2x – 27.50 %, and on average for the entire sample it was low – 2.45 %, which is not typical for Far Eastern genotypes. Regeneration was observed on calli of seven rice hybrids of four hybrid combinations: Darius 23×Oxy 2x, Sadko×Oxy 2x, Khankaisky 429×Oxy 2x and Lugovoy×Oxy 2x. Based on the results of PCR analysis, 33 plants with the resistance allele of the Pi-b gene were selected from 63 rice doubled haploids. 44 lines of doubled haploids were sown on the vegetation plot, three of which did not sprout. The collection sample Oxy 2x, being itself with a strong attachment of the grain to the panicle axis, interacting with the loci of other varieties responsible for the strength of the grain attachment, produces a phenotypes that fall of to varying degrees in the homozygous state in doubled haploids: 11 lines with an average degree of shedding, 30 lines with strong shedding. Thus, the total yield of the initial breeding material for subsequent selections in field conditions is very limited and unpromising due to the falling of the grain.

The studies were conducted to study the effectiveness of using a mesotrione-based herbicide, 480 g/l (Egida, EC) by assessing its impact on crop infestation and the productivity of poppy plants in the forest-steppe conditions of the Middle Volga region. The work was carried out in 2023–2024 on the experimental field of the Federal Research Center for Bast Fiber Crops in the Penza Region. The object of the research was the Issera oil poppy variety. The herbicide used was Egida, EC (480 g/l mesotrione) with a consumption rate of 0.25 l/ha. The experimental design included the following options: control (no treatment); manual weeding; herbicide protection. The treatment was carried out in the phase of 6–8 true leaves of poppy plants. Weather conditions during the research years corresponded to insufficient moisture (GTC 0.55 and 0.83). In poppy crops, weeds were represented by late spring weeds (64.8 %), early spring weeds (23.7 %), winter weeds (7.2 %) and perennial weeds (4.3 %). In the variant with manual weeding, the total wet weight of weeds decreased after 20 days, in relation to the control, by 96.3 %, with the use of the preparation – by 80.5 %, before harvesting – by 91.5 and 88.7 %, respectively. The protective effect of the drug lasted until the end of the poppy growing season. Moreover, the efficiency of suppression of weed components (chamomile, sow thistle) was 91.6–100 %. Against the background of herbicide protection, the seed yield increased almost to the level of manual weeding by 0.33 and 0.38 t/ha compared to the control (0.98 t/ha). The productivity of poppy increased due to an increase in the elements of the crop structure: the number of capsules, the seed productivity of the plant, and the weight of 1000 seeds. When using manual weeding and herbicide, a positive trend towards increasing the oil content of poppy seeds was noted. The increase was 0.50 and 0.31 %, respectively, relative to the control.

Poultry is a source of antibiotic-resistant and potentially pathogenic Escherichia coli, which can circulate in enterprises and enter the environment through organic waste. The aim of the study was to analyze antimicrobial resistance profiles, pathogenicity genes and phylogroups of E. coli strains circulating in poultry farms in the Perm Region. The strains of three different groups were studied: those isolated from healthy birds (n = 16), chickens with colibacteriosis (n = 28) and organic waste (n = 19). PCR was used to detect antibiotic resistance and virulence-associated genes. In each of the groups, multidrug-resistant E. coli were found in 18.8 %, 75 % and 73.7 % of cases, respectively. Up to 6 antibiotic resistance genes were detected in E. coli genomes. The beta-lactamase bla_TEM gene was found most often in all groups. More than half of the E. coli obtained from sick chickens carried bla_CTX–M. A high proportion of E. coli encoding SHV type beta-lactamase (63.2 %) was found in the organic waste. Among them, the tetA efflux system gene was detected more often, and in this group more than 20 % of E. coli had the genes encoding QnrB and QnrS proteins responsible for plasmid-mediated resistance to fluoroquinolones. Most of the strains obtained from healthy birds belonged to phylogroup E, from sick birds – to B1, isolated from organic waste – to C or E. Avian pathogenic E. coli (APEC), including high-risk clones, were found with high frequency in the group of sick birds (75 %), were found in the group of healthy birds (6.3 %) and were preserved in organic waste (63.2 %). Most of the analyzed E. coli (54 %) carried combinations of marker genes both extraintestinal and intestinal E. coli, which indicates their high zoonotic potential.

On large dairy farms of 1,200 heads or more, milking machines of the "Karusel" type with a capacity of 40 to 90 milking places have become the most widespread. The large size of the installation itself and the high mechanical load on the platform determine the increased wear of the wheel thrusters (rail-wheel). Therefore, the development of a levitating milking platform with permanent magnets is of urgent importance. The study was conducted to determine the parameters of the magnetic field generated by permanent magnets based on simulation using the Ansys Maxwell program. Three variants of magnetic assemblies were considered: with permanent rectangular, cylindrical and cubic magnets assembled in the form of Halbach arrays. The visualized results of 3D-modeling of the levitating magnetic field between movable and stationary magnetic assemblies in the form of magnetic induction lines have been obtained, allowing us to assess the overall picture of the magnetic field distribution in the air gap and beyond, and determine its force characteristics, creating the effect of levitation, as well as the number of magnetic assemblies per milking place. The average value of magnetic induction in a working gap of the magnetic assemblies made: for rectangular magnets (100 × 100 × 30mm) – 0,306 TL, cylindrical magnets (100 × 30mm) – 0,233 TL and double symmetric Assembly of Halbach (5 × 5) of the five magnets cubic form (25 × 25 × 25) – 0,539 TL. Specific repulsive forces per 1 kg elementary magnetic assemblies for rectangular magnets made – 84 N/kg cylindrical – 48,7 N/kg for the Assembly of Halbach – 314,3 N/kg. It is preferable to use Halbach assemblies when creating a levitating milking platform.

The study aimed to investigate the applicability of electron paramagnetic resonance (EPR) spectrometry for detecting the radiation treatment of spring wheat seeds using low-energy electrons. Seeds of the Iren variety (2023 crop, first reproduction) were irradiated one year after harvesting with electrons at energies of 100 and 120 keV over a dose range of 1…5 kGy (step 1 kGy), dose rate was 100 Gy/imp. Non-irradiated seeds served as the control. After irradiation, the seeds were stored in the dark at room temperature and relative humidity below 60 %. EPR spectrometry was performed 14, 28 days, 3 and 6 months after irradiation. The dose dependence of the EPR signal and its attenuation over time were studied. An increase in EPR signal intensity with increasing dose was observed. The difference in signal amplitude between samples irradiated at 100 and 120 keV, depending on the dose, reached 8…55 % at day 14 and 12…62 % at day 28 (p ≤ 0,05). In the first 14–28 days, the signal decreased by 16…38 % (100 keV) and 16…32 % (120 keV), depending on the dose. After 3 months, the intensity decreased by 5…25 % (100 keV) and 5…47 % (120 keV), relative to the data of day 28. After 6 months, the signal intensity decreased by 26…33 % (100 keV) and 26…41 % (120 keV) relative to the 3-month data. The g-factor (at the zero-crossing point of the first derivative of the EPR signal) was 2.0048, confirming the presence of carbon-centred radicals.