Biological Protection Research Articles

Human Activity Changed the Genetic Pattern of the Orchid Phaius flavus Population

Human activity often has profound effects on plant growth and evolution. Orchids are the most diverse group of flowering plants and are threatened by habitat fragmentation, over-harvesting, and urbanization. A population of Phaius flavus from Beikengding Mount (BM) in the Fujian Province of China was divided into two patches by road construction. This study evaluated its genetic characteristics using restriction site-associated DNA sequencing (RAD-seq) data, more than seven years post-road construction. The purpose of this study was to explore the impact of road construction on the evolution of isolated patches within a population. The analysis revealed that the genetic diversity of patch B was slightly higher than that of patch A in the BM population of P. flavus. Principal component and phylogenetic analyses, genetic structure and genetic differentiation analysis, and bottleneck detection indicated relatively independent genetic differentiation between the two patches. Thus, the construction of the Y013 village road may have influenced different patches of this population on a genetic level. This study provides a case for understanding the impact of specific human activities on plant populations, and then biodiversity conservation. It is conducive to formulating more effective biological protection strategies to mitigate the damage inflicted by human activities on biodiversity.

Verification of Calculation for the Protection of the Medical Cabin for Ion Therapy of Channel 26A of the Luch U-70 Project

Currently, the experience in designing installations using extracted carbon ion beams in Russia (the world) is very limited. The medical cabin for ion therapy of channel 26A of the LUCH U-70 project provides a unique opportunity for assessing the effectiveness of biological protection and verifying calculations. The paper presents data from experimental measurements of neutron radiation behind the biological protection of a medical cabin. The data were obtained for two energies of the extracted beam of accelerated carbon nuclei - 400 and 450 MeV/nucleon. The result is compared with the calculation performed using the FLUKA program for a given protection configuration. Good agreement between experimental data and calculations is shown.

Method for disrupting the reproductive pheromone bond of the cotton bollworm on sunflower crops

Background: Synthetic analogs of sexual pheromones provide an effective method of biorational control of the number of phytophagous insects based on the directed disruption of reproductive functions in populations of the target pest on the protected crop without affecting the integrity of the agrocenosis. The work aims to determine the biological effectiveness of methods of mass trapping and disorientation of the cotton bollworm (Helicoverpa armigera) to protect sunflower (Helianthus annuus) crops.Methods: The experiments were carried out in 2022-2023 in the Central Zone of the Krasnodar Territory, Russia in the stationary scientific crop rotation at the Federal Research Center for Biological Plant Protection, Krasnodar (2.5 ha) and the Kononenko farm, Novovelichkovskaya village, Dinsky district (10 ha). The biological effectiveness of elimination and disorientation methods was judged by the degree of damage to plants and buds. The disorientation effect was calculated by the number of males captured at the disorientation sites compared to the control sites.Result: The decrease in males’ search activity (disorientation effect) reached 85.3%. The damage to buds by the pest in this variant was 2.0% compared to 10.8% in the control group. In the mass trapping variant, it equaled 1.5-3.0 and 7.5%, respectively, indicating the prospects of including these techniques in the H. armigera biorational control system.Conclusion: Our findings could aid future research on insect chemical communication to develop effective biological control methods.Keywords: Biological plant protection; Sunflower; Cotton bollworm; Synthetic sex pheromones; Elimination; Disorientation; Biological effectiveness

Bugs (hemiptera) of western siberia possible agents of biological control of phytophages

The increasing harmfulness of phytophages damaging agricultural and ornamental crops is associated with various factors, in particular with the expansion of the range of pest species and the development of resistance to the chemical plant protection products used. The search and regular replenishment of the assortment of entomocarifages is becoming important in the biological protection of plants for obtaining organic crop products. An alternative to using chemical pesticides is to use natural enemies. One of the promising and numerous suborders is the hemiptera or bugs (Hemiptera: Heteroptera). The paper provides an ecological and faunal description of zoophages and zoophytophages of the order Hemiptera found in the regions of the Novosibirsk region (Moshkovsky, Bolotninsky, Chulymsky districts), Altai Territory (Troitsky district) and the Altai Republic (Ust-Koksinsky district) during the growing season of 2023. Seven species belonging to three families of the bedbug suborder were collected: Nabidae (Nabis ferus, Nabis limbatus), Anthocoridae (Orius niger), Pentatomidae (Arma custos, Zicrona caerulea, Picromerus bidens, Pentatoma rufipes). The insects were kept alive for transportation to the laboratory and study of their biological characteristics. Three species were introduced into laboratory culture. The selection of conditions for keeping predatory insectoids continues to obtain a stable laboratory population and further use in crop production. As a result of the surveys of natural and agrobiocenoses, predation by Arma custos and Pentatoma rufipes on the larvae of the Colorado potato beetle was revealed.

Methods used in sea turtle genetic and molecular studies

Sea turtles have a tropical and subtropical distribution and can be found in nearly all seas and oceans. They have been the subject of considerable genetic research. However, it does not yet appear that the molecular techniques used for these genetic studies follow a consensus or universal set of tools to be followed for subsequent studies. This is not desirable since it may preclude data exchange and use among studies. Thus, the aim of this review was to survey the main genetic and molecular methods used for sea turtle research worldwide. To achieve this goal, a total of 95 scientific papers were compiled from online databases. We considered articles that used molecular tools for genetic analysis and provided detailed locality data. The following aspects were assessed: species studied, local of sample collection, type of tissue used for molecular studies and type of genetic material used. The seven known sea turtle species have different distribution patterns, with some overlapping of occurrence. Chelonia mydas has been studied genetically along the coasts of all continents. Skin is the most common type of tissue used for molecular analyses. From genetic studies on sea turtles, it is possible to verify the occurrence of hybridism. This phenomenon is relevant to the conservation of the species and was reported in six articles on this topic. Therefore, it is considered that genetic and molecular assays in sea turtles are important tools for biological evaluation and protection. The aim was to survey the main methods used in genetic and molecular research on marine turtles. Keywords: DNA, Chelonian, Testudines, marine turtles

Fluorinated B-72 hybrid silver doped modified nanoparticle as a coating for biological corrosion protection of ancient bricks

In this paper, a superhydrophobic organic-inorganic composite coating containing fluorinated B72 hybrid methyl-modified silica/(Ag doped TiO2) by hexamethyldisilazane (HMDS) (H-SiO2/Ag/TiO2) was prepared by means of a mild and an environmental friendly method. Transparency, adhesion, hardness tests and photocatalytic performance were measured to determine the content of Ag in TiO2 which the TiO2/AgNO3 ratio is 0.008 g/mL. The synthesized Ag/TiO2 nanoparticles were characterized by X-ray diffraction (XRD), Raman spectra and transmission electron microscope (TEM). The highest contact angle of coated ancient bricks was 148.66° and the color change value of ΔE⁎ before and after coating was <5 which is within an acceptable range. The physical properties such as apparent porosity and water vapor permeability (ΔMp) were studied. After weathering from acid, alkali, salt, water and ultraviolet radiation, the bricks coated by the composite coatings still have good hydrophobicity that the contact angle were >120° and minor degree of surface corrosion comparing with the ancient bricks. The inhibitory effect of the composite coating on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), and that on algae (Chlamydomonas and Dunaliella) were studied through bacteriostasis test and algae comparative experiments, respectively. Finally, the mechanism of the composite coating on antibacterial and anti-algae was studied. The results showed that the appearance of the ancient bricks was not changed after coating, and the anti-weathering, antibacterial and anti-algae properties of the ancient transformation were increased.

The nanocellulose fiber scaffold to construct a hierarchical phenolic coating on cotton fiber surfaces for inactivating pathogens through an enhanced protein adsorption mechanism

Emerging pathogens present a significant societal threat, and biological protection textiles are expected to play a pivotal role in controlling their spread. However, incorporating highly effective pathogen transmission-blocking abilities into textiles while ensuring their large-scale production remains challenging. This work has successfully developed a hierarchically structured coating for cotton fibers, which exhibits enhanced antiviral and antibacterial functionalities compared to existing phenolic coating methods. The multilevel coating consisted of a cellulose nanofibers (CNFs) scaffold on cotton fibers, along with a phenolic layer constructed of 4,4-bis(4-hydroxyphenyl)valeric acid (DPA) on the CNF surfaces. The bioactive textile exhibited remarkable antiviral and antibacterial capabilities with exceptional durability, while demonstrating strong protein affinity for pathogen destruction. Especially, the CNFs with diameters below 10 nm show significant size effect in capturing phi6. This is primarily due to their complementary shape matching the spike proteins, resulting in an increased number of binding sites and improved inactivation effectiveness. Moreover, the modification process was demonstrated to be scalable in a pad-dry-cure line commonly employed by textile finishing factories, and the resultant coating ensured reliable safety for human skin without sacrificing wearing comfort. This approach opens up new possibilities for developing protective textiles that effectively block pathogen transmission.

EVALUATION OF TECHNOLOGICAL PLASTICITY OF HIGH BORON CORROSION-RESISTANT STEEL DURING HOT DEFORMATION OF PIPES USED FOR SPENT NUCLEAR FUEL STORAGE

Statement of the problem. The sustainable development of the global nuclear power industry in the future depends on how effectively the problems of radiation safety and nuclear proliferation are addressed. Such problems occur, among other things, at the final stage of the nuclear fuel cycle – spent fuel management. This task is currently on the agenda of both the international community and national governments of countries that develop or intend to develop nuclear energy [1−3]. Today, in connection with ensuring the safety of nuclear energy, boron-containing steels are widely used in the world practice as a material for biological protection and for the manufacture of special equipment parts. This is due to the fact that the B10 isotope in steels provides neutron capture [4]. Hexagonal pipes made of high-boron steel were needed to shield the support cover of the compacted spent fuel storage facility at nuclear power plants. Corrosion-resistant steels alloyed with boron are widely used in the nuclear power industry due to their special nuclear properties. During the operation of nuclear power plants, fuel assemblies that have served their useful life must be stored in special storage facilities using containers – hexagonal tubes made of 04Сr14Ti3B2V steel. To reduce costs during in the construction and operation of NPPs, part of the spent nuclear fuel management should be performed at Ukrainian enterprises. This will provide a significant import substitution effect. To manufacture hexagonal tubes from 04Сr14Ti3B2V steel according to the ingot-hot deformation-profiling-heat treatment scheme, it is necessary to develop the parameters of hot deformation and subsequent technological operations. The use of these pipes in compacted spent fuel storage facilities of NPPs will allow to increase the storage capacity by 2 times, which will give a significant national economic effect Material and methods of research. Material used for the study was steel 04Сr14Ti3B2V (CS-82), smelted using two variants (vacuum-induction – “VI” and vacuum-induction followed by vacuum-arc remelting – (“VD”). Steel grade 04Сr14Ti3B2V belongs to high-alloy, corrosion-resistant ferritic steels with a high boron content of up to 2 %. The method of differential thermal analysis was used to study the phase transformation temperatures in the steel. X-ray diffraction and micro-X-ray spectral analysis were used to assess the phase state. The steel samples were tested for weldability After cooling, the welded samples were subjected to X-ray transmission [5]. Hot twisting tests and mechanical tests at high temperatures were also performed. The macro- and microstructure of the metal was studied. Results. The macro- and microstructure of steel was evaluated depending on the smelting method. The phase composition of the steel was studied. The study of the plastic properties of steel ChS-82 by means of penetration and hot twisting tests showed that the temperature range of maximum plasticity is in a wide range (from 1 025 to 1 150 0C) with a rather low resistance to deformation. During hot deformation in the temperature range of 1 175 0C and above, metal fracture was observed along the grain boundaries at the melting points of the Cr−Fe−B boride phase. The optimal temperature range for hot deformation of steel ChS-82 is 1 000−1 050 ⁰С. Scientific novelty. For corrosion-resistant high boron steel used for spent nuclear fuel storage, the temperature range of hot deformation was selected and the structural and phase composition was estimated, which will allow deforming the metal on the piercing mill and manufacturing pipes.

Biological protection of spring barley from root rot under the conditions of the Republic of Mari El

Biological protection of spring barley from root rot under the conditions of the Republic of Mari El

Fungal secondary metabolite gliotoxin enhances enzymatic activity in soils by reshaping their microbiome

Gliotoxin (GT) is a sulfur-containing epidithiodioxopiperazine produced by various filamentous fungi, including those used in biological plant protection (Trichoderma virens). The pronounced antimicrobial effect of GT on a variety of fungi and bacteria makes it a promising agent for controlling phytopathogens in agricultural systems. In this study, we aim to investigate the microbiological properties of the soil microbiome after the introduction of GT. GT was applied at doses of 10, 25, 50, 100 and 500 μM kg−1 soil. Soil sampling was carried out after 1, 7, 14, 30, 60 and 90 days of incubation. It was found that GT significantly stimulated the respiratory activity of soil microorganisms and maintained this activity throughout the experiment. Carbon of microbial biomass, on the contrary, decreases under the influence of GT and is restored at the end of the experiment only in microcosms with 10 and 25 μM GT. Separate estimates of bacterial and fungal biomass showed that the bacterial community increased in biomass on day 14, while fungal biomass increased on day 30 after the treatment. Under the influence of GT, the activity of soil enzymes involved in the carbon (CB, βG, βX), nitrogen (NAG, LAP) and phosphate (AP) cycles significantly increased. High-throughput amplicon sequencing of the ITS and 16S rDNA markers revealed that the soil fungal community is more susceptible to GT than the bacterial community. This was reflected in changes in alpha-diversity indices and in the pattern of changes in the abundance of some microbial genera. Thus, on the one hand, the data obtained provides insight into the biological effects of GT on the soil microbial community. On the other hand, it sets the direction for further research into the ecological role of antibiotics produced by soil and rhizosphere microorganisms.

Development of Edible Coatings Based on Pineapple Peel (Ananas Comosus L.) and Yam Starch (Dioscorea alata) for Application in Acerola (Malpighia emarginata DC).

Acerola fruit has great nutritional and economic relevance; however, its rapid degradation hinders commercialization. The use of coatings reduces post-harvest biochemical modifications and provides physical and biological protection for vegetables such as acerola. This study developed and characterized an edible coating made from pearl pineapple peel flour (PPPF) and yam starch (YS) to preserve the quality standards of acerola fruits during storage at room temperature and under refrigeration. The edible coating, composed of 4 g of PPPF, 3 g of starch, and 10% glycerol, presented excellent moisture content (11%), light tone (L* 83.68), and opacity (45%), resistance to traction of 27.77 Mpa, elastic modulus of 1.38 Mpa, and elongation percentage of 20%. The total phenolic content of the coating was 278.68 ± 0.45 mg GAE/g and the antioxidant activity by DPPH was 28.85 ± 0.27%. The quality parameters of acerolas were evaluated with three treatments: T1-uncoated fruits; T2-fruits coated with 1% glycerol; and T3-fruits coated with PPPF-YS. The T3 treatment reduced the weight loss of stored acerolas, maintaining the light and bright color of the fruits, and delayed the decrease in soluble solids, especially in refrigerated fruits. Therefore, edible coatings based on pineapple flour and yam starch are effective technologies for controlling the physical and physicochemical parameters of acerolas during storage, benefiting the post-harvest quality of this fruit.

Blockchain-based proxy re-encryption access control method for biological risk privacy protection of agricultural products

In today’s globalized agricultural system, information leakage of agricultural biological risk factors can lead to business risks and public panic, jeopardizing corporate reputation. To solve the above problems, this study constructs a blockchain network for agricultural product biological risk traceability based on agricultural product biological risk factor data to achieve traceability of biological risk traceability data of agricultural product supply chain to meet the sustainability challenges. To guarantee the secure and flexible sharing of agricultural product biological risk privacy information and limit the scope of privacy information dissemination, the blockchain-based proxy re-encryption access control method (BBPR-AC) is designed. Aiming at the problems of proxy re-encryption technology, such as the third-party agent being prone to evil, the authorization judgment being cumbersome, and the authorization process not automated, we design the proxy re-encryption access control mechanism based on the traceability of agricultural products’ biological risk factors. Designing an attribute-based access control (ABAC) mechanism based on the traceability blockchain for agricultural products involves defining the attributes of each link in the agricultural supply chain, formulating policies, and evaluating and executing these policies, deployed in the blockchain system in the form of smart contracts. This approach achieves decentralization of authorization and automation of authority judgment. By analyzing the data characteristics within the agricultural product supply chain to avoid the malicious behavior of third-party agents, the decentralized blockchain system acts as a trusted third-party agent, and the proxy re-encryption is combined with symmetric encryption to improve the encryption efficiency. This ensures a efficient encryption process, making the system safe, transparent, and efficient. Finally, a prototype blockchain system for traceability of agricultural biological risk factors is built based on Hyperledger Fabric to verify this research method’s reliability, security, and efficiency. The experimental results show that this research scheme’s initial encryption, re-encryption, and decryption sessions exhibit lower computational overheads than traditional encryption methods. When the number of policies and the number of requests in the access control session is 100, the policy query latency is less than 400 ms, the request-response latency is slightly more than 360ms, and the data uploading throughput is 48.7 tx/s. The data query throughput is 81.8 tx/s, the system performance consumption is low and can meet the biological risk privacy protection needs of the agricultural supply chain. The BBPR-AC method proposed in this study provides ideas for achieving refined traceability management in the agricultural supply chain and promoting digital transformation in the agricultural industry.

Crops biological protection: Phytopathogens growth inhibition by the entomopathogens

Background: The safety of agrarian preparations used for crop protection is a critical issue. In these regards, the minimization of usage of chemical pesticides containing artificial harmful substances is very important. Thus, the elaboration of innovative harmless biopesticides, based on biological enemies of pests, is very desirable. Microbe-based biopesticides can significantly increase the quality of agricultural production. Objectives: This research aims to develop ecologically safe, entomopathogenic microbe based biopesticides for use in green agriculture to improve agricultural production qualityIt includes the quality of vegetables, cereals, and fruits, as well as meat, milk, and eggs from animals that consume plant-based feed cultivated using recommended methodologies. Context and purpose of this study: This article was devoted to the consideration of bactericide effect of non-cellular extracts of entomopathogens against the various phytopathogens, as the potential prospective innovation for elaboration of plant protection safe biopesticides. Results: The majority of the studied entomopathogens can synthesize the compounds which inhibit the growth of phytopathogens. Entomopathogenic strains BT 2675, BL 200-4, and LS 2728 were found to significantly inhibit the growth of phytopathogens such as Pectobacterium, Xanthomonas, Rhodococcus, Curtobacterium, and Pseudomonas genera. According to spectroscopy the antiphytopathogenic effect is caused by an active component which is probably lipoprotein complex. Further detailed research on this is planned. Conclusions: Non-cellular extracts of entomopathogenic Bacillus are effective against the various plant pathogens. The identified antimicrobial properties of non-cellular extracts of entomopathogenic can be potentially used for the elaboration of plant protection safe biopesticides. Keywords: Bacillus thuringiensis (BT), Brevibacillus laterosporus (BL), Lysinibacillus sphaericus (LS), non-cellular extract, phytopathogen, entomopathogen, safe biopesticide

Integrated Design and Simulation of Helicopter Nuclear, Biological, and Chemical Protection System

Integrated Design and Simulation of Helicopter Nuclear, Biological, and Chemical Protection System

INNOVATIVE HOSE GAMMA FLAW DETECTOR “RID 50W”

An innovative model of a portable class hose gamma flaw detector “RID 50W” is presented, equipped with environmentally friendly tungsten components: a biological protection unit, a shutter assembly and a multi-link source holder for working with emitters based on 75Se and 192Ir. The design features of the radiation head model, the principles of release and shutdown of the radiation beam in the “RID 50W” apparatus, issues of optimization, synthesis, and computer engineering of critical components are considered, and a quantitative assessment of the technical parameters and characteristics of the equipment is presented. The exposure dose rate of the diffusion flux of penetrating gamma radiation from a working emitter based on 192Ir was calculated in the Geant4 software package, followed by practical verification using standard dosimetric monitoring tools. Conclusions based on the results of verification of the obtained data are presented. The design and operating principle of a patented laser sight designed to expand the functionality of a hose gamma flaw detector during operation, including in critical conditions of structural constraint, is also considered.

Current research by scientists of the department for agricultural sciences of the Russian Academy of Sciences

The results of scientific papers reviewed at the meetings of the Bureau of the Department for Agricultural Sciences of the Russian Academy of Sciences in 2023 are presented. The main attention was paid to the state and development of domestic breeding and seed production of vegetable crops; analysis of the genetic resources of Crimean plants for the development of domestic breeding of fruit, berry crops and grapes; laser and spectral technologies in the production of agricultural products; innovative technologies for biological protection of animals; scientific support for the prevention of land desertification; rational land use in the context of natural, climatic and social challenges; digitalization of food systems; training of a new generation of young researchers in the field of agricultural sciences.

ПОЧВЕННЫЕ БАКТЕРИИ ИЗ АВТОХТОННЫХ МИКРОБНЫХ СООБЩЕСТВ ЦЕНТРАЛЬНОЙ СИБИРИ В БИОЛОГИЧЕСКОЙ ЗАЩИТЕ ПШЕНИЦЫ ОТ ALTERNARIA TENUISSIMA

The most powerful soil bacteria from autochthonous microbial communities of Central Siberia against phytopathogenic fungi Alternaria tenuissima were selected. Isolation from soil samples and cultivation of bacterial isolates were performed on the artificial nutrient medium for bacteria PD-agar. Antagonistic activity was measured on GRM Saburo. In this case, Alternaria tenuissima was sown in a dish on GRM Saburo, and the selected bacterial strains were sown around the micromycete. As a result of joint growth of the test culture and soil bacteria, the most powerful antagonists in the suppression zone of Alternaria tenuissima were identified. The most powerful bacteria-antagonists in reducing the intensity and prevalence of root rot were identified by the method of artificial infection of Alternaria tenuissima. Before infection with micromycete, bacterization of spring wheat seeds Novosibirskaya-15 with the studied bacterial isolates was carried out. Mathematical processing of the obtained results was fulfilled by one-way variance analysis and two-sample F-test for variance. The results of the study on the use of soil autochthonous antagonist microorganisms in biological protection of spring wheat from the causative agents of root rot Alternaria tenuissima showed that the studied bacterial isolates statistically significantly (p &lt; 0.01) reduced the intensity and prevalence of this disease. The maximum effect in reducing the intensity and prevalence of the disease was shown by isolates B2 and B4 (according to preliminary identification of Bacillus sp.). Also, the studied bacterial strains showed a positive effect on the length of sprouts. At the same time, isolate B2 showed a statistically significant (p &lt; 0.001) effect on the length of spring wheat sprouts. The stimulating effect was manifested in an increase in the length of sprouts compared to the control. Therefore, this strain can be recommended not only for protection against Alternaria tenuissima, but also for stimulating wheat growth.

Serial cell culture passaging in vitro led to complete attenuation and changes in the characteristic features of a virulent porcine deltacoronavirus strain.

Porcine deltacoronavirus (PDCoV) is an important enteric coronavirus that has caused enormous economic losses in the pig industry worldwide. However, no commercial vaccine is currently available. Therefore, developing a safe and efficacious live-attenuated vaccine candidate is urgently needed. In this study, the PDCoV strain CH/XJYN/2016 was continuously passaged in LLC-PK cells until passage 240, and the virus growth kinetics in cell culture, pathogenicity in neonatal piglets, transcriptome differences after LLC-PK infection, changes in the functional characteristics of the spike (S) protein in the high- and low-passage strains, genetic variation of the virus genome, resistance to pepsin and acid, and protective effects of this strain when used as a live-attenuated vaccine were examined. The results of animal experiments demonstrated that the virulent PDCoV strain CH/XJYN/2016 was completely attenuated and not pathogenic in piglets following serial cell passage. Genome sequence analysis showed that amino acid mutations in nonstructural proteins were mainly concentrated in Nsp3, structural protein mutations were mainly concentrated in the S protein, and the N, M, and E genes were conserved. Transcriptome comparison revealed that compared with negative control cells, P10-infected LLC-PK cells had the most differentially expressed genes (DEGs), while P0 and P240 had the least number of DEGs. Analysis of trypsin dependence and related structural differences revealed that the P10 S protein interacted more strongly with trypsin and that the P120 S protein interacted more strongly with the APN receptor. Moreover, the infectivity of P240 was not affected by pepsin but was significantly decreased after exposure to low pH. Furthermore, the P240-based live-attenuated vaccine provided complete protection to piglets against the challenge of virulent PDCoV. In conclusion, we showed that a PDCoV strain was completely attenuated through serial passaging in vitro. These results provide insights into the potential molecular mechanisms of PDCoV attenuation and the development of a promising live-attenuated PDCoV vaccine.IMPORTANCEPorcine deltacoronavirus (PDCoV) is one of the most important enteropathogenic pathogens that cause diarrhea in pigs of various ages, especially in suckling piglets, and causes enormous economic losses in the global commercial pork industry. There are currently no effective measures to prevent and control PDCoV. As reported in previous porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus studies, inactivated vaccines usually elicit less robust protective immune responses than live-attenuated vaccines in native sows. Therefore, identifying potential attenuation mechanisms, gene evolution, pathogenicity differences during PDCoV passaging, and immunogenicity as live-attenuated vaccines is important for elucidating the mechanism of attenuation and developing safe and effective vaccines for virulent PDCoV strains. In this study, we demonstrated that the virulence of the PDCoV strain CH/XJYN/2016 was completely attenuated following serial cell passaging in vitro, and changes in the biological characteristics and protection efficacy of the strain were evaluated. Our results help elucidate the mechanism of PDCoV attenuation and support the development of appropriate designs for the study of live PDCoV vaccines.

Оценка приемов формирования урожайности и посевных качеств семян подсолнечника на участке гибридизации и в потомстве F1

The research was conducted in the V.S. Pustovoit All-Russian Research Institute of Oil Crops in 2022–2023. In 2022, we studied effect of agrotechnical methods of cultivation (fertilizers, chemical plant protection, fertilizers combined with chemical plant protection, and biological plant protection) on a hybridization plot on yield and sowing qualities in F1 seed of a sunflower hybrid Surus. The obtained seeds were divided into three fractions (large, middle, and small) and treated with an insecticide-fungicide composition (Kruizer, EC – 10 l/t + Apron Gold, WE – 3 l/t + Maxim, SC – 5 l/t) before the estimation of their germination (in laboratory and field). The studied cultivation methods, fractions, and seed treatment influenced positively the laboratory and field seed germination of the hybrid Surus, which was equal 94-97 and 88–91%, respectively. Consequently, these methods are effective in sunflower hybrid seed growing to produce seeds with high sowing qualities. In 2023, we studied germination, yield and quality of commercial seeds of the hybrid Surus, using for planting F1 seeds produced on the hybridization plot in 2022. We determined the application of fertilizers both separately or jointly with chemical ways of plant protection as well as usage of treated seeds of large and middle fractions on the hybridization plot provided the highest meanings of field germination of seeds (in average 90%), yield (3.20 t/hа), oil content in seeds (50.4%), and oil yield (1.45 t/hа).

BIO PROTECTIVE TREATMENT OF WOOD

The article covers issues related to biological protection of wood. It is shown that wood, especially chopped (dead) wood is exposed to both external natural factors and the action of various microorganisms. Natural factors, especially ultraviolet rays of solar radiation, change the chemical composition of wood and destroy lignin as the least stable part of wood. Wood is more intensively destroyed by various microorganisms ‒ bacteria and fungi. Wood contains many nutrients - starch, sugar, fats, compounds of nitrogen, phosphoric acid, sulfur, potassium, calcium and magnesium. All of them are an excellent environment for the settlement and reproduction of various microorganisms. It is noted that among hardwoods, beech wood is most negatively affected by microorganisms, especially in the warm period of the year. This wood is a valuable breed from which furniture, planed veneer and various parts and products in the construction industry are made. Therefore, it is very important to keep it intact and attractive for a long time by treating it with bioprotective agents. The purpose of the research is to determine the biostability of beech wood after its treatment with bioprotective agents. An analysis of the biological destruction of wood and the use of protective materials was conducted and it was established that the paucity of data to explain and describe the bioprotection process, the neglect of environmentally safe means leads to the biodestruction of wooden structures under the action of microorganisms. A bioprotective agent based on copper oxychloride, nickel sulfate and soda ash was used in a certain ratio of components. Control and treated samples of beech wood were placed in the prepared soil and after 60 days the weight loss of the samples was determined. Studies have shown that the biostability of beech wood treated with a bioprotective agent is 4.3 times higher than that of untreated samples. The idea of the reproduction of microorganisms in the material and their death has been revealed, which, accordingly, shows changes in the metabolic processes of the vital activity of microorganisms. It has been established that the use of treated surfaces oil-wax and azure reduces the biodegradation process by more than 8 times for untreated samples. Keywords: beech wood, bioprotective treatment, bioprotective agents, biostability determination method, mass loss, treatment efficiency.