Aim of this work is to substantiate the hypothesis that the absence of lice in bats is associated with the electrification of the surface of their body during the flight.

Discussion. The paper analyzes the physical phenomenon of friction electrification, the triboelectric series of substances with special attention to the objects of atmospheric electricity, and the Cohen rule that relates the dielectric properties of a substance to its permittivity. The electrical properties of the atmosphere are described including the occurrence of a potential difference between the Earth's surface and the ionosphere and the mechanism of maintaining this potential as a result of charging the ground with negative electricity by thunderstorms. The results of experimental data on the formation of a positive electrostatic charge on the surface covers of insects and birds are presented. It is hypothesized that the hair and skin membranes of bats should also be positively electrified during flight. The reasons that prevent lice from living in electrified bat hair are described. It is proposed to explain the presence of developed sebaceous glands in bats as a way of discharging electrostatic charge before returning to the shelter and the bell structure of the hair cuticle as a device for retaining the secretion of sweat glands.

Conclusion. The absence of lice in bats is a direct consequence of their adaptation to active flight.

Aim. To perform a morphological study of seal lice (Anoplura: Echinophthiriidae) of the genus Antarctophthirus Enderlein, 1906 taken from Northern fur seals (Callorhinus ursinus L., 1758) at Tyuleniy Island, Okhotsk Sea, Russia).

Material and Methods. Seal lice were collected from the nasal passages of Northern fur seal C. ursinus pups during a scheduled ecological and virological expedition to Tyuleniy Island in August 2017. Fourteen samples of seal lice (11 imago males, 1 imago female, 1 nymph of the 2nd age, 1 nymph of the 3-rd age) were stored in 70% ethanol at room temperature from the time of collection until the start of the study. Morphological features of the insects were studied using light and scanning electron microscopy and compared with the available data in the scientific literature.

Results. Unique patterns of the arrangement of spines were found in the examined samples that is a sufficient species feature for representatives of this family and allows the identification of a new species of seal lice.

Conclusion. A new species of seal lice, Antarctophthirus nevelskoyi n.sp., was identified and described and named after the famous Russian explorer of the Far East, Admiral Gennady Ivanovich Nevelskoy (18131876).

Aim. The aim of this work was to study the chromosome set of some representatives of smooth-nosed bats of the North Caucasus.

Material and Methods. Various research methods were used to achieve this goal, including that of dried preparations (the main method for obtaining chromosomal preparations) and that of constructing karyograms.

Results. A comparative analysis of the karyological data of 11 species of smooth-nosed bats of the North Caucasus was undertaken and the karyological characteristics of the species accepted in the latest reports on the fauna of Russia and the Caucasus were clarified. The similarity of G -bands in large pairs of meta- and submetacentric chromosomes in Myotis blythi, Myotis mystacinus, Pipistrellus pipistrellus, Pipistrellus kuhli and Vepertilio murinus with bands in small and medium-sized acrocentric chromosomes such as in Eptesicus seotinus may indicate the evolution of the karyotype of the first species by Robertsonian translocation, i.e. compounds of acrocentric chromosomes of Eptesicus serotinus in various combinations. When comparing karyotypes in the family Vespertilionidae, it was found that the karyotype of Eptesicus serotinus is "archaic" (2n=50, NFa=48). With the help of karyological data, the authors composed schemes of phylogenetic relationships of genera in the family Vespertilionidae, which differ to a certain extent from the schemes compiled by taxonomists for representatives of this family.

Conclusions. Based on the results obtained, we can conclude that the karyotype of Eptesicus serotinus is the most primitive among the representatives of the order of bats. The primary role in the evolution of this group was played by Robertsonian rearrangements and pericentric inversions (reduction of NFa and 2n from 50 to 38).

Aim. To study the polymorphism of the genes calpastatin (CAST), somatotropin (GH) and differential growth factor (GDF9) of sheep of the Dagestan mountain breed.

Material and Methods. Studies on the genetic typing of Dagestan mountain sheep according to CAST, GH and GDF9 genes were carried out in conditions of distant pasture farming in the Republic of Dagestan by the Genetics and Breeding Laboratory of the Federal Agrarian Scientific Centre of the Republic of Dagestan, an accredited laboratory of immunogenetics and DNA technologies of the All-Russian Research Institute of Sheep and Goat Breeding and a branch of the North Caucasus Federal Scientific Agrarian Centre. These investigations were undertaken by the PCR-RFLP method (polymyrase chain reaction - restriction fragment length polymorphism) on a Tersik four-channel programmable thermal cycler from DNA-Technologia (Russia) using specific primers synthesized in the SYNTHOL research and production laboratory (Moscow).

Results. Carrying out PCR-RFLP revealed breed-specific alleles with different frequency of occurrence, which was: in the locus of the CAST gene - allele CAST^N - 0.03; allele CAST^M - 0.97; at the GH gene locus - GH^A allele - 100.0, GH^B allele - 0; in the locus of the GDF9 gene - the GDF9^A allele - 0.25, the GDF9^G allele - 0.75, which determined the frequency of occurrence of the homo- and heterozygous genotypes: CAST^NN, CAST^MM and CAST^NM - 93.0; 0 and 7.0%; GHA^A, GH^BB and GH^AB - 100.0 and 0%; GDF9^AA, GDF9^GG and GDF9^АG- 16.0, 66.0 and 19.0%, respectively.

Conclusion. The regularity revealed can be considered as an ecological factor that optimizes the adaptive functions of the sheep's organism, on the one hand, an evolutionary selection process that contributes to the creation of a specific way of genetic structures in the population, on the other. The assumption is made that the information obtained can serve as the beginning of a more in-depth study of the unique gene pool of sheep of the Dagestan rock breed for its further improvement. Variants of genetic marker profiles of parental pairs are proposed for accumulation in breeding herds bred in different ecological-geographical zones and genotypes of carriers of selection-significant genetic structures.

Aim. The purpose of this research was to study the sustainability of Institute bred sweet cherry cultivars to spring frosts during flowering by the method of artificial freezing and to identify resistant cultivars.

Material and Methods. Seven Institute bred sweet cherry cultivars were studied: 'Adelina', "Malysh", "Orlovskaya Rozovaya", "Orlovskaya Feya", "Podarok Orlu", "Siyana" and "Trosnyanskaya". Spring frosts were simulated in an "Espec" PSL-2KPH climate chamber in early May at -1°, -2°, -3° and -4°C. At each temperature regime, 100 pcs of flowers and buds of each cultivar were taken in 3-fold repetition. Temperature was lowered at the rate of 1°C per hour. The duration of exposure to negative temperatures was 3 hours.

Results. Damage to the stamens and pistils was assessed by the darkening of the tissues. In buds and blooming flowers after frosts, the pistils were first damaged but the stamens were not. Resistance to spring frosts decreased with the phenological development of the cherry's generative organs. The beginning of damage to the flowers as a result of the artificial freezing was noted at a temperature of -1°C. At the same time, the high stability of cherry buds was noted. Modeling frosts of -2°...-4°C increased the number of dead flowers and buds. The resistance of sweet cherries to spring frosts was found to depend on the genotype and stage of development of reproductive organs. A different sum of active temperatures for the beginning of flowering and ovary formation was noted, indicating the onset of phenological phases in which generative organs are susceptible to spring frosts.

Conclusion. The experiment made it possible to distinguish a medium-resistant cultivar "Malysh" which was resistant to spring frosts. Weakly stable genotypes were "Orlovskaya Rozovaya", "Orlovskaya Feya", "Trosnyanskaya" and "Siyana". Unstable cultivars were "Adelina", and "Podarok Orlu". During the formation of the ovary, the greatest potential for resistance to spring frosts was shown by "Podarok Orlu".

Aim. To study the influence of cultivation technology on the number of ecological and trophic groups of microorganisms and the yield of winter wheat on the common chernozem of the Central Caucasus.

Material and Methods. The number of microorganisms was determined by counting colonies on dense nutrient media according to generally accepted methods.

Results. The number of microorganisms that transform organic and mineral forms of nitrogen and soil yeast was determined, depending on meteorological conditions, soil cultivation and fertilizers. Mineral fertilizers had the most significant effect on the activity of the soil microbiota. In years of varying moisture availability, fertilizers improved the nutrient regime of the soil, which contributed to increased plant development, microflora activity and increased winter wheat yield. In both the technologies applied, the largest number of all groups of microorganisms studied was observed when applying a complete mineral fertilizer -N52P52K52 .This dose of fertilizer also provided the highest yield of winter wheat - 6.07-6.33 t/ha. With a balanced plant nutrition regime (N52P52K52), the processes of decomposition and mineralization of plant residues proceeded at the same rate in both technologies. At the same time, without the use of fertilizers, the total activity of microorganisms in the no-till technology exceeded the minimum technology by 23.4х105 columnforming units, which indicates the beginning of the process of self-healing of the soil in the third year after the transition to direct sowing of crops.

Conclusion. The number of microorganisms is one of the most sensitive indicators of the direction of complex biochemical processes, allowing us to assess the combined influence of all factors on the overall state of the soil microbiocenosis.

Aim. To analyze the regional systems of location of Specially Protected Natural Areas within the Ural-Siberian sector of Russia's steppe and forest-steppe zones.

Discussion. The territory of the study includes the following regions: Orenburg, Chelyabinsk, Kurgan, Tyumen, Omsk, and Novosibirsk Regions, the Republic of Bashkortostan and Altay Territory. Each of these areas has its particularities of SPNA location that are component of the ecological framework. Ecological frameworks on the regional and local levels are the models of stable land use and of biological diversity conservation. The determination of model systems of Specially Protected Natural Areas is necessary to reach a balance between a comfortable and favorable environment for the life of the population and the protection of unique natural heritage. The rational allocation of SPNAs promotes optimizing the territorial structure of nature management, the stable functioning of biological processes, and local development within regional natural borders.

Conclusion. It was ascertained that the SPNA allocation system of each examined region had its peculiarities connected with natural objects. Protected territories with federal, regional and local significance are located only in Chelyabinsk and Novosibirsk regions and Altay Territory. Also, positive dynamics in forming a new SPNA are observed in the Chelyabinsk and Tyumen regions and Altay Territory (data for 2019-2020). An excellent balance and development of the protected territories system are seen within the Ural-Siberian regions. The location of the SPNA system within the foothill regions of the Ural-Siberian sector (Altay Territory and Cheleyabinsk region) is the closest to the classical etalon of the ecological framework's formation.

Aim. To assess the interrelations of chemical and physical-chemical parameters of soil cover properties with climatic factors of soil formation in agricultural landscapes of the Central Chernozem Region (CCR) of Russia.

Materials and Methods. The research was carried out using a systemic analysis of the complex of agroclimatic and soil parameters. Soil properties were assessed by the weighted average characteristics of arable soils for the areas of the Central Chernozem Region. Hydrothermal conditions were taken into account by rainfall, temperature and the amount of active temperatures for the period 1960-2000.

Results. Estimated excess of annual precipitation (440-640 mm) over evaporation (407-500 mm) in the average annual cycle ensures the formation of total runoff and soil washability in the amount of 40-150 and 17-104 mm. This determines soil acidity (pH_KCL, R² = 0.36...0.73). Optimal conditions of humus accumulation are formed when the humidity factor is 0.8-0.9. Mesorelief is a factor of spatial heterogeneity of the total soil composition with which 85% of physical-chemical properties and up to 70% of nutrient availability are associated.

Conclusion. The differences in the hydration of the territories both at the scale of the CCR and local levels determine the intensity of geochemical runoff, the oxidation-reduction regime and total chemical soil composition which constitute the basis of heterogeneity in the content of organic matter, acidic-base and other properties.

Aim. Assessment by nitrification index values of the level of trophicity and toxicity for aquatic organisms in the waters of a small watercourse in an urbanized area by the content of nutrients in the water and its selfcleaning ability.

Materials and Methods. The concentration of compounds of nutrients in the waters of the river was determined using the "Kapel 104T." system of capillary electrophoresis. Water was sampled for analysis according to GOST R 51592- 2000. The water content of readily oxidized organic compounds was assessed by the magnitude of permanganate oxidizability (PND F 14.1; 2.4.154-99) and difficultly oxidized compounds by the magnitude of the chemical oxygen consumption (RD 52.24.421-2012). Assessment of the water trophic level was evaluated by measuring the content of various forms of mineral nitrogen and mineral phosphorus. The aggregation index characterizing the toxicity of various forms of mineral nitrogen to aquatic organisms was calculated by their ratio to MPC for fishery reservoirs. The nitrifying ability of river waters was estimated by the value of the nitrification index (Initr.), calculated by the ratio of the concentration of nitrogen of nitrates in water to the sum of the concentrations of various forms of mineral nitrogen and the self-cleaning ability by the values of the nitrification index.

Results. In terms of the aggregation index, water at all sampling points was found to be toxic. The river ecosystem is characterized by a weak ability to cleanse itself and a weak nitrifying ability, which is associated with the influence of numerous cyanotoxins on the microbiocenosis of the watercourse and filtration organisms.

Conclusion. It was shown that the most sensitive indicator of trophicity of river waters is the concentration of the mineral phosphorus. Through measuring the ratio of the concentrations of mineral nitrogen to mineral phosphorus, it was established that blue-green algae (cyanobacteria), producers of cyanotoxins, dominate in the phytoplankton of the river in all the points studied.

Aim. This study was an attempt by the authors to identify the impact of oil production in the Caspian Sea on the quality of waters surrounding oil and gas-production platforms.

Material and Methods. In 2018, by order of the Committee for Forestry and Wildlife of the Ministry of Agriculture of the Republic of Kazakhstan, Kazekoproekt carried out comprehensive marine research to assess the state of biological resources in the eastern part of the Caspian Sea. All studies were carried out according to standard methods accepted in international practice. Samples were collected in summer (July-August) 2018 and autumn (September) 2018.

Results. An analysis of the materials of environmental studies carried out in the water area of the eastern part of the Caspian Sea in 2018 established the absence of biogenic concentrations in sea water in excess of the standard indicators. It was found that in the waters surrounding several stations in summer and autumn, concentrations of oil products were exceeded. The concentrations of pesticides in the waters of the northern Caspian Sea recorded in 2018 were not detected.

Conclusion. It was found that in the eastern part of the Caspian Sea in 2018 there was no concentration of biogenic elements in sea water above the standard indicators. Of the heavy metals, an excess of maximum permissible concentrations was found only at one station - of copper in the summer over 159 sq. m and in the autumn over 121 sq. m. Of particular concern is the fact that at several stations in summer and autumn excessive concentrations of petroleum products were recorded. The concentrations of pesticides in the waters of the northern Caspian Sea recorded in 2018 were not detected.

Aim. To identify the effect of biological preparations applied with or without nitrogen fertilizers for crop by-product, their incorporation into the soil on the decomposition of plant residues and composition of mobile humus substances in typical slightly eroded chernozem.

Materials and Methods. The study was carried out in the field experimental station of Kursk FARC in the cycles of cereal and cereal-row crop rotations in variants with by-product treated with biopreparations; with applied biopreparations + nitrogen fertilizers; with applied nitrogen fertilizers and without biopreparations. To study decomposition the content of unhumified organic matter was determined in the topsoil by the monolith method after by-product incorporation into the soil and 3045 days after their decomposition. Simultaneously the composition of mobile humus substances in the soil was determined.

Results. The decomposition of crop by-product and after harvesting and root residues mixed with it in the soil and treated with biopreparations or nitrogen mineral fertilizers was studied for the first time. The peculiarities of the effect of the factors studied on the degree of plant residue decomposition and the composition of mobile humus substances were shown.

Conclusion. It was determined that treating the by-product of barley, buckwheat and sunflower with bioproducts, both with applied nitrogen fertilizers and without them, contributed to the increase in the degree of plant residue decomposition as compared with the control and nitrogen mineral fertilizer application. In the years which are favourable according to hydrothermal conditions the improved quality of mobile humus substances of the soil influenced by biopreparations are noted and under extreme conditions the tendency to the improvement of their quality is observed.

Aim. Investigation of the effectiveness of a DNA insecticide with a high level of environmental friendliness on Diaspis echinocacti Bouche in the greenhouse of the Nikitsky Botanical Garden.

Materials and Methods. The object of the study was the insect pest Diaspis echinocacti Bouche. The number of D. echinocacti larvae was identified on segments of Opuntia ficus-indica L. (Mill.) using a Nikon SMZ 745T microscope and computer microphotography. In the experiment, the effectiveness of the DNA insecticide "Cactus-NBG" on D. echinocacti was studied, the preparation "Tanrek VK", VRK, from the class of neonicotinoids being used as a standard insecticide.

Results. It was revealed that the treatment with the DNA insecticide "Cactus-NBG" against D. echinocacti larvae had a significant insecticidal effect. The biological effectiveness of the preparation was 82.0%. The mortality of larvae after treatment significantly increased in comparison with the control (p<0.05) and was measured at 43.2±5.0%, 53.2±2.3%, and 84.2±2.2% on the 3^rd, 7^th, and 14^th day after treatment respectively.

Conclusion. As a result of treatment of O. ficus-indica against D. echinocacti with the contact DNA insecticide "Cactus-NBG", a significant insecticidal effect was found. On the 14^th day after treatment, the mortality of D. echinocacti in "Cactus-NBG" was 84.2±2.2%, in the "Tanrek" group - 86.0±1.4% and in the control group treated with water -11.2±1.2%. The biological effectiveness of "Cactus-NBG" on the 14^th day was 82.0%. Thus, the preparation "Cactus-NBG", based on the antisense fragment of the D. echinocacti genome, caused a significant mortality of the target insect pest and can compete with modern chemical preparations.

Aim. To undertake floristic zoning of the Samur-Chirakhchay interfluve and Dzhufudag for the analysis of the species composition of petrophylic complexes.

Material and Methods. A list of obligate petrophytes was compiled based on the results of processing the authors' own field collections and taking into account information from floristic reports and determinations. The assessment of similarity of species composition of petrophytes in the regions was carried out using the Jaccard (Kj) and S0rensen-Czekanowski (Ksc) coefficients.

Results. A subdivision of the mountain area studied into 7 floristic regions was carried out, based on a comparison of floristic lists and the presence of endemic species.

Conclusion. The tendency in petrophytes to isolation of species forms, arising from spatial isolation relating to habitat specificity, makes it possible to quite accurately draw boundaries corresponding to the natural boundaries of differentiation of floras.