№ 2 (2025)

Background. Fungi of the genus Fusarium are representatives of a biologically heterogeneous group, which includes saprophytes and facultative parasites. Traditional morphological methods for identifying representatives of this genus are often not reliable enough due to the variability of features and the complexity of the Fusarium solani species complex. Materials and methods. The review analyzes modern molecular genetic methods based on the analysis of sequences of markers such as ITS, TEF-1α, RPB2, β-tubulin, NIR, PHO and the SIX gene, which have significantly increased the accuracy of diagnosis, making it possible to distinguish closely related species, races and specialized forms. Recently, special attention has been paid to the advantages of the multilocus approach, which is recognized as the “gold standard” for the identification and taxonomic analysis of Fusarium solani representatives. This research also examines the potential and limitations of next-generation sequencing (NGS), including WGS, tNGS, and mNGS, for comprehensive genomic analysis and diagnostics of pathogens. Results and conclusions. It is noted that the integration of phenotypic and molecular data, as well as the development of genomic technologies, open up new prospects for standardization and increased accuracy of Fusarium solani identification at the species and intraspecific levels.

Background. Among pets, a special place is occupied by the domestic dog (Canis familiaris), which is one of the most common pets. The diversity of its ecological and social status is determined by the peculiarities of reproduction and reproduction in cities and rural settlements and the degree of socialization. The purpose of the study was to conduct research on the ecological features of the spatial structure and population size of a domestic dog in a multi-storey building in Penza. Materials and methods. The material for the work was the results of surveys of stray dogs in the central part of the Arbekovo microdistrict in Penza, conducted in the winter of 2025. Dogs were counted using the route method. Absolute abundance and density values were used as the main estimated indicators of animal distribution. The features of the placement of dogs were assessed by the facts of the concentration of animals near any socio-cultural object or building, as well as by the results of correlation analysis. When accounting for stray dogs, in addition to the meeting place, gender, age (adult, puppy) and breed were recorded. Results. The analysis of dog records in 6 quarters of the Arbekov residential area revealed certain patterns in the placement of dogs, and also showed some dependence of the density and number of dogs on the characteristics of the technogenic structure of the studied residential areas. An analysis of the absolute number of dogs indicates an uneven occurrence of animals in all the studied accounting quarters. The number of domestic dogs is positively correlated with the size (number of houses) of the private sector (r = 0.835, p = 0.04), and the number of semi-free (conditionally employed) dogs is positively correlated with the number of parking lots in the registered quarters (r = 0.894, p = 0.02). Conclusions. The conducted studies of 6 quarters of the Arbekov residential area in Penza (24 % of the area of the area) have shown that urban environmental factors have little effect on the number of stray dogs. To a greater extent, the number, sex and breed composition of the urban dog population depends on the autonomous demographic processes that occur in the established territorial groupings of stray dogs, as well as on the human factor (maintenance and breeding). Any reliable relationships are noted only for individual environmental factors and individual accounting categories of dogs.

Background. The oil-bearing rocks of the Orenburg region were selected for the study: dolomite, limestone, clay-siltstone rock, sandstone, the utilization of which is a modern environmental problem. A study was conducted on the toxicity of drilled rocks for living organisms after thermal processing. Materials and methods. The drilled rock, which together with the drilling mud and drilling wastewater, is a waste at the well construction stage, was studied by the method of delayed fluorescence for oil content and biotesting using watercress. Results. It is shown that each geological rock containing oil, depending on its structure and chemical composition, has a certain range of values of the delayed fluorescence coefficients, by which it can be identified in the composition of drill cuttings. With an increase in the oil content in the rock, the value of delayed fluorescence decreases. The standards for delayed fluorescence of drilled rocks containing and not containing oil are established, which can be used to determine the oil content in drilled rocks. Conclusions. When germinating seeds after firing on dolomite and limestone, toxic conditions are created for plants and the drilled rocks cannot be used directly as artificial soil, as well as sludge from a torch. Limestone and dolomite can be used in construction, as an ameliorant or to create artificial soil with specified properties. The most optimal is the use of clay-siltstone rock and sandstone directly for reclamation.

Background. Fresh surface water bodies are exposed to many anthropogenic and natural factors that can have a significant negative impact on the structure and functions of the entire ecosystem. Despite the fact that many efforts are being made to assess and manage the quality of surface waters, the problem of their pollution remains relevant to this day. The purpose of the study is a comprehensive environmental assessment of the state of Lake Malakhovo (Orenburg, Russia) based on organoleptic, generalized and hydrochemical indicators for 2022–2023. Materials and methods. The studies were carried out at three sites located both in the immediate vicinity and at the maximum distance from pollution sources using the following methods: photometric (determination of nitrite and nitrate nitrogen content), atomic absorption (establishment of iron mass concentration), titrimetric (determination of calcium, magnesium, sulfate ions and mass concentration of carbonates) and fluorimetric method (measurement of mass concentration of oil products). All studies were conducted in an accredited laboratory. Conclusions. According to the main organoleptic indicators, the water of the studied reservoir meets the quality criteria, with the exception of suspended substances, for which maximum excesses of up to 5.5 MPC (maximum permissible concentration) are observed in the autumn period, as a result of which the lake waters are classified as dirty (quality class V). For individual substances (iron and magnesium ions, sulfate ions, nitrites), excess of the maximum permissible concentration of fishery value was recorded. The ecological state of the waters in terms of nitrate and nitrite content in all sections deteriorates in the winter to quality class V. Exceeding the maximum permissible concentration of cultural and household value was not recorded. According to the results of calculating the hydrochemical pollution index, the water of the lake. Malakhovo (Orenburg) is classified mainly as moderately polluted, with the exception of the first section, located in close proximity to pollution sources, where the water in the autumn period is considered polluted.

Background. Annual losses of grain crops in the world from pests amount to one percent of the harvested crop. Many species of rodents have become permanent inhabitants of agrocenoses and significant pests of fields, gardens, and vegetable gardens. The noted problem sets tasks for regular monitoring of numbers, measures to reduce and maintain the number of rodents at a level safe for humans. The purpose of the study is to assess the species composition, number of rodents living in sheepfolds, farms and other agricultural facilities in a number of areas of the foothills of Dagestan. Materials and methods. The material was collected in the summer at agricultural facilities (crop fields, vegetable gardens, sheepfolds, warehouses, hangars) and in natural biotopes of the Kayakent and Sergokalinsky districts of the Republic of Dagestan in 2021–2022. To assess the species diversity of rodents in the considered conditions, the Simpson diversity index was used. All captured animals were measured for body weight and standard body measurements. In addition, the physiological state of the genitals was analyzed during the autopsy: the weight of the testicles, the number of blue spots or embryos in the uterus were determined. To study the species composition, abundance, and structure of the rodent community, quantitative and qualitative methods of rodent counting using Gero crushers were used. Results. The results showed that the species richness of rodents in natural biotopes was higher than in agricultural facilities. In both areas, the yellow-bellied mouse and the social vole dominated. The number of rodents and the density of burrows in agricultural facilities were more than twice as high as in the natural environment. The species diversity index was higher in the natural environment. The body condition and reproduction rates of rodent species were higher in agricultural facilities than in natural environments. Conclusions. Rodent species richness was higher in natural conditions than in agricultural facilities. The species diversity index was higher in natural biotopes than in agricultural facilities. The dominant status (in abundance) was occupied by the yellow-bellied mouse in both conditions. The number of rodents in agricultural facilities was more than twice as high as in the natural environment. Individuals in agricultural facilities were fatter and had higher fertility values than in natural spaces. A threshold of economic damage was revealed.

Background. The accumulation of salts in soils is often accompanied by a change in pH to the alkaline side, technogenic salinization can be accompanied by an acidic reaction of the soil. Under conditions of salinization and acidic reaction of the environment, plants experience osmotic and oxidative stresses. The purpose of the research was to study the reactions of oat plants to the combined effects of NaCl salinity and acidic soil reaction according to some physiological and biochemical parameters. Materials and methods. Avena sativa L. oats of the Steyer variety were used as the object of the study. The plants were grown in a model experiment on a background sod-podzolic soil with various combinations of pH (pH 4.9 and pH 7.3) and salinity (0.5 % NaCl). A neutral medium (pH 7.3) was created by the addition of CaCO3. Salinity was created in % relation to the dry weight of the soil. The control was a saline–free variant with a pH of 7.3. 4 and 8 days after the appearance of seedlings in the leaves of plants, hydrogen peroxide was determined by the ferrothiocyanate method, catalase activity was determined permangatometrically, and peroxidase function was determined by the method of A.N. Boyarkin. Morphometric parameters were recorded within 8 days after the emergence of seedlings. Results. Compared with the control, growth processes slowed down more strongly in the variants of the experiment with salinity and were arranged in the following order: pH 4.9 + NaCl > pH 7.3 + NaCl > pH 4.9. The H2O2 content in oat leaves in the experimental variants did not differ or minimally differed from the control during the first observation period, but in the second period it was 1.6–1.7 times higher in all experimental variants. Catalase activity in both observation periods was higher than the control in the variants with salinity by 10–30 %. In the second follow-up period, catalase activity was generally one-third lower compared to the first in all studied variants. The activity of peroxidases in oat leaves in all experimental variants was significantly higher than in the control variant in both experimental periods. In the second follow-up period, peroxidase function was higher in comparison with the first in all studied variants (by 16–81 %). Conclusions. The greatest depression of oat plants, judging by morphometric indicators, was observed at the initial stages of the experiment (the first 4 days), especially in the experimental version combining salinization and acidic soil reaction. Catalase was actively involved in the adaptation of plants to the conditions of salinity and soil acidity at this stage, and peroxidase by the 8th day of the experiment.