Abiotic Environmental Factors Research Articles

Dynamics of change in the number of amphibian larvae in pond conditions and factors determining it in the central part of Belarus

The aim of the work is to study the influence of factors of abiotic and biotic origin on abundance, growth rate and development of amphibian larvae in natural conditions.The scientific novelty of the work lies in studying the degree of interaction of amphibian larvae with each other and with invertebrate predators, their interaction in natural conditions. The main part of the work contains a literature review, the work methodology and the result description.In conclusion, it was noted that under natural conditions, the magnitude of impact of predators on the number of amphibian larvae is much lower than it has been previously thought; they are not able to provide a significant function of regulating the number of tadpoles. Abiotic environmental factors, being within the optimum limits, do not affect the mortality of larvae, and food in natural water bodies is not a factor limiting abundance. The most intensive death of larvae occurs in the early larval development stage. Despite a low overall density of larvae in a natural water body, most amphibian larvae are periodically exposed to metabolites and are affected by the “group effect”. This is expressed in the inhibition of growth and development of individuals, the death or decrease in the decline in the viability of the most sensitive individuals, and also increases the likelihood of their death from other factors.

The Function of Root Exudates in the Root Colonization by Beneficial Soil Rhizobacteria.

Soil-beneficial microbes in the rhizosphere play important roles in improving plant growth and health. Root exudates play key roles in plant-microbe interactions and rhizobacterial colonization. This review describes the factors influencing the dynamic interactions between root exudates and the soil microbiome in the rhizosphere, including plant genotype, plant development, and environmental abiotic and biotic factors. We also discuss the roles of specific metabolic mechanisms, regulators, and signals of beneficial soil bacteria in terms of colonization ability. We highlight the latest research progress on the roles of root exudates in regulating beneficial rhizobacterial colonization. Organic acids, amino acids, sugars, sugar alcohols, flavonoids, phenolic compounds, volatiles, and other secondary metabolites are discussed in detail. Finally, we propose future research objectives that will help us better understand the role of root exudates in root colonization by rhizobacteria and promote the sustainable development of agriculture and forestry.

Diversity and colonization of butterfly (Lepidoptera) on Pasoso Island, Central Sulawesi

Various biotic and abiotic environmental factors influence the preservation of butterfly species in an area. The pressure and threat of extinction for butterflies that occupy relatively narrow and isolated habitats such as small islands are pretty large. This study aims to estimate the diversity of butterfly species, predict colonization, predict local extinction of butterflies, and conservation implications to minimize local extinction of butterflies in the habitat type on Pasoso Island, Central Sulawesi Province. Data was collected using field observations in four land cover types (primary forest, gardens, “ecoton” between garden-primary forests, and shrubs) on a 100 m line transect line. Each line transect is divided into point counts, with a distance between points of 100 m. The results of the identification of butterfly species in four habitat types on Pasoso Island found 16 species from 78 individual butterflies belonging to four families (Nymphalidae, Papilionidae, Pieridae, and Lycaenidae). Butterflies in all habitat types on Pasoso Island are in the moderate category. Species diversity in garden habitat types based on the analysis of the Shannon-Wiener index showed higher than other habitat types (H'=1.89), while the Ecoton habitat type has the lowest diversity value (H'=1.06). The results of the t-test showed that there was no significant difference in the diversity of butterfly species in the four habitats. The results showed that colonization and local extinction occurred in butterfly species on Pasoso Island. Four of the nine species are included in the extinct category, namely Apias albina, Family Lycaenidae, Ideopsis juventa, Phalanta alcippe celebensis Wallacea. Five other species were colonized, namely Arhopala araxes, Catochrysops strabo, Catopsilia pomona, Hypolimnas anomala, and Idea blanchardii.

Divergent geographic variation in above‐ versus below‐ground secondary metabolites of Reynoutria japonica

Abstract Secondary metabolites play an important role in plant adaptation, because they can mitigate biotic and abiotic environmental stresses. However, their production and allocation incur different costs and benefits, and are therefore subject to trade‐offs, which are less studied. To understand large‐scale geographic patterns of secondary metabolites, and their environmental drivers and trade‐offs, we studied 39 natural populations of the perennial herb Japanese knotweed (Reynoutria japonica) along a large latitudinal gradient in China. We measured the concentrations of six polyphenols in leaves and rhizomes of R. japonica, and associated the variation in these metabolites with biotic and abiotic environmental factors as well as with functional plant traits and putative costs of secondary metabolites. We found that climate was an important driver of variation in secondary metabolites, both above‐ and below‐ground. Remarkably, the patterns of association differed between leaves and rhizomes, as well as between putative low‐cost versus high‐cost compounds. While annual mean temperature was a stronger predictor of above‐ground metabolites, annual precipitation was more frequently associated with variation in below‐ground metabolites. Moreover, annual temperature was positively associated with high‐cost metabolites, but negatively with low‐cost metabolites. Above‐ground secondary metabolites were generally more strongly associated with functional traits (e.g. specific leaf area) than below‐ground metabolites, and in all cases the directions of correlation were opposite for low‐cost versus high‐cost metabolites above‐ground. The patterns of association also varied with latitude such that leaf concentrations of low‐cost metabolites (quercetin) increased but those of high‐cost metabolites (resveratrol, piceid and emodin) decreased at higher latitudes. In rhizomes, in contrast, the concentrations of high‐cost metabolites (piceid and emodin) increased with latitude. Synthesis. Our findings indicate that allocation strategies differ between above‐ and below‐ground tissues of Reynoutria japonica. As latitude increases, R. japonica invests relatively more into below‐ground metabolites. We propose that reduced high‐cost metabolites in the leaves at higher latitudes may help to conserve nutrients after defoliation, while maintaining high‐cost metabolites in rhizomes may be important for persistent allelopathic effects and resource conservation below‐ground. The divergent patterns of above‐ and below‐ground metabolite allocation thus likely reflect the multiple functions of metabolites and the plants' adaptation to different environments.

Ranking of the Territory of Sochi by the Risk of Infection with HFRS Using the Method of Maximum Entropy

Relevance. Hemorrhagic fever with renal syndrome (HFRS), due to the severity of the course and high mortality, poses a serious threat to the health of the population of both the city of Sochi and its guests. Therefore, in order to implement more effective and less economically costly anti-epidemic and preventive measures, it is very important to constantly monitor the activity of the natural focus of HFRS, as well as to have a clear idea of the territories most dangerous for the risk of infection with this infection.Aims. Assessment of the epidemiological significance of the territory of the city of Sochi for the risk of infection with HFRS based on the maximum entropy method using a geographical information system.Materials & Methods. Based on the application of the maximum entropy algorithm implemented in the MaxEnt program, as well as the ArcGIS 10 program.8. Ranking of the territory of the city of Sochi according to the risk of infection with HFRS was performed. The paper uses: data on positive epizootological findings (a total of 131) for 2016-2021, which were obtained from the Sochi branch of the Federal Medical Institution «Center of Hygiene and Epidemiology in the Krasnodar Territory», the Sochi branch of the Federal Medical Institution «Black Sea Plague Station» of Rospotrebnadzor, as well as the Stavropol Plague Control Research Institute of the Rospotrebnadzor; materials on environmental conditions from the Biolclim data bank, vegetation index for 9 months (https://land.copernicus.eu/global/products/NDVI ). Preliminary preparation of the information was carried out using the ArcGIS 10 program.8. As a tool for building a training model, the MaxEnt program version 3.4.4 was used (https://biodiversityinformatics.amnh.org/open_source/maxent /).Results and discussion. The practical implementation of the tasks was to obtain maps of the epidemiological significance of the territory for the risk of infection with HFRS by superimposing the points of occurrence of the species (reservoir and carrier of HFRS) on maps of abiotic environmental factors affecting its spread. The implementation of this work consisted of the sequential implementation of four main stages: the first – the collection, generalization and transformation of bioclimatic and epizootic-epidemiological data; the second – the selection of the most significant data for the construction of the model; the third – the ranking of the territory of the city. Sochi on the risk of the spread of HFRS using GIS; the fourth is the analysis of the data obtained. In the course of the work, a model was obtained that allows dividing the study area according to the degree of risk of infection with HFRS with a high degree of reliability and significant prognostic value.Conclusions. The use of the model makes it possible to obtain new, more detailed data from a spatial point of view on the boundaries of potentially dangerous sites in the region in terms of GLPS. In particular, this applies to those territories where positive epizootological findings and cases of infection with HFRS have not been previously noted.

Fungal Microbiome of Alive and Dead Korean Fir in its Native Habitats

A rapid decline of Abies koreana has been reported in most of the natural alpine habitats in Korea. It is generally accepted that this phenomenon is due to climate change even though no clear conclusions have been drawn. Most research has focused on abiotic environmental factors, but studies on the relationships between A. koreana and soil fungal microbiomes are scarce. In this study, the rhizoplane and rhizosphere fungal communities in the alive and dead Korean fir trees from its three major natural habitats including Mt. Deogyu, Mt. Halla, and Mt. Jiri in Korea were investigated to identify specific soil fungal groups closely associated with A. koreana. Soil fungal diversity in each study site was significantly different from another based on the beta diversity calculations. Heat tree analysis at the genus level showed that Clavulina, Beauveria, and Tomentella were most abundant in the healthy trees probably by forming ectomycorrhizae with Korean fir growth and controlling pests and diseases. However, Calocera, Dacrymyces, Gyoerffyella, Hydnotrya, Microdochium, Hyaloscypha, Mycosymbioces, and Podospora were abundant in the dead trees. Our findings suggested that Clavulina, Beauveria, and Tomentella are the major players that could be considered in future reforestation programs to establish ectomycorrhizal networks and promote growth. These genera may have played a significant role in the survival and growth of A. koreana in its natural habitats. In particular, the genus Gyoerffyella may account for the death of the seedlings. Our work presented exploratory research on the specific fungal taxa associated with the status of A. koreana.

ВЕТСАНЭКСПЕРТИЗА И МОРФОЛОГИЯ КРОВИ МОЛОДИ ВОБЛЫ ПРИ ПАРАЗИТАРНОЙ ИНВАЗИИ

A study of the morphological parameters of the peripheral blood of juvenile volva during parasitic invasions by trematodes A. muehlingi and P. cuticula was carried out to study the degree of negative impact of these parasites on early juvenile vobla. The analysis confirmed that parasitic invasion influenced changes in hematological parameters. A natural increase in the number of neutrophils and eozonophils in infested fish was shown. Reliably high rates of young erythrocytes were revealed, twice as high as in fish free from parasites. The identified deviations in the composition of the white blood of juvenile roach were due to the protective mechanism and immunological reactions of the body to infection by parasites. The presence of degenerative forms of erythrocytes in blood smears of both infected and uninfected early juvenile vobla may indicate that these changes are caused not only by the parasitic load, but also by negative changes in abiotic environmental factors.

Addition of Exogenous Organic Ameliorants Mediates Soil Bacteriome and Microbial Community Carbon Source Utilization Pattern in Coastal Saline–Alkaline Soil

Knowledge regarding how abiotic and biotic environmental factors operate in soil microbiome reassembly remains rudimentary in coastal saline–alkaline soils amended by different organic ameliorants. In this study, field trials were conducted to investigate the impacts and underlying mechanisms of sewage sludge (S) and sludge-based vermicompost (V) at the application amounts of 0, 50, and 100 t ha−1 on soil physicochemical characteristics, carbon source utilization pattern, and bacteriome in coastal saline–alkaline soils. Results revealed that impacts of the organic ameliorants on soil’s physicochemical and microbial attributes were highly dependent upon the carbon types and amounts applied. Unsurprisingly, applying sewage sludge and vermicompost significantly alleviated environmental constraints, such as saline–alkaline stress and nutrient deficiency, with lower pH, salinity, and higher soil organic carbon content observed in organics-amended soils. Specifically, higher microbial substrate metabolic activity, but lower diversity was observed in saline–alkaline soils amended by organic ameliorants. In addition, reassembled bacteriomes harboring distinguishable core and unique community profiles were observed in reclaimed soils as compared to unamended saline–alkaline soil. Procrustes analysis showed that the soil microbial utilization pattern of carbon sources was significantly related to the alterations in their physicochemical property and bacterial core microbiome. Additionally, Redundancy Analysis (RDA) revealed that soil core bacteriome reassembly was dominated by the integrated impacts of soil salinity, successively followed by carbohydrates, amino acids, polymers, pH, soil organic carbon (SOC), and available nitrogen (AN). Overall, this study provides a comprehensive understanding of soil abiotic and biotic determinants in bacteriome assembly in coastal saline–alkaline soil remediation mediated by organic ameliorants.

Apple trees varieties of VNIISPK selection in production

The creation and improvement of adaptive apple assortment for industrial gardening in the Central zone of Russia is the main goal of the continuous work of breeders and specialists of related specialties of VNIISPK. A group of apple cultivars of various maturation periods has been created for both industrial gardening and amateur household farms. These apple cultivars are characterized by high adaptability to abiotic and biotic environmental factors, suitability for modern industrial production; they have attractive fruits with excellent taste and high content of biologically active substances. Fifteen VNIISPK cultivars are immune to scab along with a complex of economically valuable traits. The presence of the gene of immunity to scab in cultivars leads to a decrease in the fungicidal load in the orchard and, as a consequence, to the ecologization of fruit products. Nineteen VNIISPK apple cultivars are triploid. This biological feature is of great economic importance. Triploid cultivars are characterized by high-quality fruits, more regular fruiting and high yield. Seven triploid cultivars are also immune to scab, which increases their value. The share of apple cultivars of our breeding recommended for the Central Chernozem region is 44%, and for the Central region - 23% of the total apple assortment. Our apple cultivars not only satisfy the traditional tastes of the population, but are also characterized by a complex of biological and economically valuable features that allow them to be successfully introduced into intensive orchards, thereby playing an important role in solving the problem of import substitution of fruit products and year-round provision of fresh apples to the population. In many areas of the Central and Central Chernozem regions of Russia, the orchards are planted with VNIISPK cultivars. In Altukhovo LLC, Tula region, these orchards occupy 540 hectares. The average level of profitability of cultivation of 6 cultivars of VNIISPK breeding in this farm has amounted to 72.8% over the past five years. In the joint-stock company "Dubovoye" (Tambov region), the total area with our apple cultivars is 167.2 hectares with a profitability of 73.7%. In the “Komsomolets” stud farm (Tambov region), the average level of profitability for three VNIISPK cultivars occupying 48 hectares has amounted to 125.7% over the past five years.&

Tracing the serendipitous genesis of radiation resistance.

Free-living organisms frequently encounter unfavorable abiotic environmental factors. Those who adapt and cope with sudden changes in the external environment survive. Desiccation is one of the most common and frequently encountered stresses in nature. On the contrary, ionizing radiations are limited to high local concentrations of naturally occurring radioactive materials and related anthropogenic activities. Yet, resistance to high doses of ionizing radiation is evident across the tree of life. The evolution of desiccation resistance has been linked to the evolution of ionizing radiation resistance, although, evidence to support the idea that the evolution of desiccation tolerance is a necessary precursor to ionizing radiation resistance is lacking. Moreover, the presence of radioresistance in hyperthermophiles suggests multiple paths lead to radiation resistance. In this minireview, we focus on the molecular aspects of damage dynamics and damage response pathways comprising protective and restorative functions with a definitive survival advantage, to explore the serendipitous genesis of ionizing radiation resistance.

Assessment of the influence of abiotic environmental factors on the distribution of bream and carp in the Northern Caspian

Changing habitat conditions is an important driving force affecting the distribution of fish in the range. A quantitative assessment was made of the influence of environmental factors on the distribution of bream Abramis brama Linnaeus, 1758 and carp Cyprinus carpio Linnaeus, 1758 in the waters of the eastern part of the Northern Caspian. The number was estimated based on the results of research net catches. The preferred temperatures and habitat depths of bream and carp in the shallow zone of the Northern Caspian are shown. The colleof field material was carried out during complex expedition observations in 2014 and 2020. The installation of nets with a mesh of 30–200 mm was carried out in the shallow-water zone of the eastern part of the Northern Caspian. Bream and carp in the Northern Caspian Sea form concentrations in areas with depths up to 6–8 m. In the time interval from the end of April to October, bream was observed in the temperature range from 7.0 to 28.5 °C, carp — from 5.5 to 28.0 °C. A mathematical assessment of the influence of depth, temperature and water transparency on the number of these fish species was carried out. The obtained regression models took into account from 44.9 to 80.1% of the factors determining the number of fish in the studied water area. Carp are more sensitive to the effects of temperature, depth and transparency compared to bream. The obtained results provide a theoretical basis for predicting changes in the habitat of fish due to abiotic environmental factors, which is relevant in connection with pronounced climatic changes

Comparative physiological and immunological assessment of carp crosses

The main purpose of hybridization in the aquaculture industry is improving the productivity of hybrids compared to their parents in specific environmental conditions. The physiological state and resistance are judged by blood parameters, which are sensitive and informative indicators of the state of the body’s defense power and allow timely detection their changes under the influence of abiotic and biotic environmental factors. The article presents the results of studying of the productive and physiological properties of two-year-old carp crosses: interbreed hybrids of the first generation (F1). Shown, that the driveability index of the new threebreed carp cross is significantly lower than that of the “Surskiy Malokostny” and “Petrovskiy” crosses, which characterizes its high commercial qualities. The new three-breed cross has a lower swim bladder index: the lengths of the anterior and posterior chambers are almost equal. The number of vertebrae is less, compared to others. However, in the caudal region the number of vertebrae is close to that of the “Sursky Malokostny” cross and greater than that of the “Petrovsky”. In terms of size and weight indicators, the two-year-olds of the new three-breed carp cross exceeded those of other studied crosses, which indicates significant production potential. All recorded blood parameters of the studied fishes were within the limits of the physiological norm. The new three-breed cross is characterized by a high level of nonspecific cellular protection: a large proportion of microphages — segmented neutrophils is noted in the blood leukogram of the new cross. High immune resistance is evidenced by high vitality and a relatively low content of cationic protein in the lysosomes of neutrophils, which is consumed during immune defense when preparing fish for wintering. A comparative assessment of the crosses showed their excellent and productive marketable qualities, survival at different stages of ontogenesis, and good physiological and immunological status.

Analysis of population size of Pterygoplichthys multiradiatus and its intake of microplastics in streams with different land uses

Most freshwater habitats have been substantially affected by anthropogenic factors such as fish introductions, plastic pollution, and river regulation. Urban rivers are highly vulnerable to impacts associated with land use changes resulting from increasing urbanization, including altering habitat and establishing aquatic biological communities in these areas. In turn, the introduction of exotic species into sensitive and threatened ecosystems such as tropical urban streams and their rapid establishment, such as Pterygoplichthys multiradiatus, was used as an ecological model to determine the relative population size of the species. Also, the species was used to evaluate the presence of microplastics (MPs) in the gastrointestinal tract (GIT) of fish in rivers with different land use history. Our results showed significant differences in pleco abundance between areas with high and low urban (LU) development in the watersheds. The study demonstrated that abiotic environmental factors directly influence the relative abundance of plecos at the range and watershed scales. In a total of 42 fish examined, only 85.7% showed MPs retained in the GIT, with fibers and fragments being the most common. A total of 22 pieces of microplastic were identified with Nile Red staining by slide analysis. A significant difference was found between the abundance of microplastic ingested per total fish length between streams with high and LU development reaches. Therefore, in relatively small amounts, microplastic ingestion appears to be common in P. multiradiatus species, regardless of the habitat in which they are found and the diet present.

Seasonal Occurrence of Melon Fruit Flies (Zeugodacus cucurbitae Coq.) and Its Natural Enemies on Bitter Gourd

Aim: To study the seasonal occurrence of cucurbit melon fly and correlation study with weather parameters to know the impact of abiotic environmental factors on the activity of melon fruit fly concerning infesting the fruits of bitter gourd in crop ecosystem.
 Place and Duration of Study: College of Agriculture, VNMKV Parbhani, Maharashtra. Studies during two seasons Rainy and Summer 2021 and 2022 respectively.
 Methodology: The experimental plot was kept unsprayed throughout the crop season. The observation was recorded as soon as the incidence was noticed from five randomly selected plants at weekly intervals. The observations of fruit flies were recorded from the day of fruit formation to the last picking of the fruit. The damaged and healthy fruits were recorded at eachpicking to knowing the percentage fruit infestation by fruit flies.
 Results: Fruit fly was the major pest of bitter gourd in fruit damage. The fruit damage record range was 15.65 to 59.33 per cent in the rainy season whereas, 28.99 to 61.14 per cent in the summer season. The per cent fruit infestation shows a significant and positive correlation with no. of maggots per fruit (r = 0.857 and 0.905) during both seasons respectively. Weather parameters like morning relative humidity (MRH) and rainfall the during rainy season show significant and positive correlation (r = 0.87 and r = 0.71 respectively) whereas, during the summer season significant and positive correlation (r = 0.77) with MRH and significant and negatively correlated with (r = - 0.66) minimum temperature. The record of larval pupal parasitoid Psyttalia fletcheri (Silvestri) and it was discovered that 16% of the population was parasitized during the experimental period
 Conclusion: The infestation may vary from season to season, region to region and concerning variety also. Here the infestation range was higher during the summer season, which may be because of the coincidence with the fruit season of mango in that area.

MORPHOLOGICAL FEATURES AND PRODUCTIVITY OF THE ATROPA L. GENUS SPECIES, CULTIVATED IN THE MOSCOW REGION

Background. The application of the anatomical method of studying various forms, varieties and species will allow to determine the degree of plant adaptation to habitat conditions and to assess its ecological plasticity.
 Purpose. This work aim is to evaluate the species and breeding samples of the Atropa genus by a set of signs, including morphological description, shape, size and weight of leaves, the nature of the pubescence of the leaf plade epidermis, location, size and number of stomata, as well as the yield of raw materials.
 Results. All collection samples of the studied species of the genus Atropa in the conditions of the Non-Chernozem zone of the Russian Federation undergo a full cycle of development. The assessment of the potential resistance of 14 forms and species of belladonna to unfavorable biotic and abiotic environmental factors was carried out, their main morpho-anatomical features were studied. The adaptive potential of the leaves of the studied Atropa plants is due to the variability of the structural elements of the leaf epidermis and is one of the factors of resistance to stress. In the group of studied samples, A. acuminata (406, Lithuania) and A. belladonna (487, Poland) have the lowest stress-adaptive potential (according to the set of signs). It was noted that populations of A. belladonna from Eastern Europe and France have signs of xeromorphism against the background of a decrease in plant size compared to the control and the lowest yield. It is noted that A. belladonna samples from Europe with yellow corolla staining occupy an intermediate value in yield in the presence of xeromorphic signs, which indicates their adaptability to the conditions of agrocenosis. The presence of numerous secreting trichomes in the studied accessions of A. belladonna and A. komarovii (nos. 5 and 14) may indicate their potential resistance to diseases and pests. The A. caucasica and A. komarovii species, as well as the A. belladonna specimen from Great Britain (no. 1), can be considered well adapted.
 Conclusion. The highest-yielding populations are from Russia A. belladonna 15/15; A. caucasica 118 compared to the Bagira variety. These samples can be considered promising and well-adapted candidates for creating a new variety of A. belladonna.

Evaluation of alfalfa varieties by economically valuable characteristics in the southern foreststeppe zone of the Republic of Bashkortostan

The purpose of the research (2019–2022) is to identify promising alfalfa samples based on a complex of economically valuable traits that are resistant to biotic and abiotic environmental stress factors for the conditions of the Republic of Bashkortostan. The novelty of the research is that for the first time in the conditions of the southern forest-steppe zone of the Republic of Bashkortostan, new promising hybrid populations with ecological plasticity and increased yield potential were studied. Records and observations were carried out according to the VIR method. As a result of the research, promising cultivars were identified that combine high feed and seed productivity. Samples of Emerald (variegated hybrid) High-protein (variegated hybrid population), Precocious (variegated hybrid population), Tatar pasture differ in the earliest flowering. The largest excess of the green mass yield was noted by samples: From 3-8 (blue hybrid, created by individual — family selection) exceeding the standard by 37.4%; Population 25 (mixture) by 33.2%; P 85044 (blue hybrid, created by individual and family selection) by 29.3%; Population 8 (synthetic population, belongs to the yellow–variegated hybrid variety type) by 27.7%. A positive correlation was established between the seed yield, the amount of precipitation (r = 0.481) and GTC (r = 0.470). The presence of a weak negative correlation between the seed yield and the average daily temperature regime (r = -0.276) was revealed. The results of the research can be used in the selection of alfalfa in the Republic of Bashkortostan, Russia and is of interest to researchers-breeders of the world community.

Creation and introduction into production of a new variety of soft winter wheat for cultivation in fallows and the best non-fallow predecessors

Relevance. Winter wheat is the main food crop in Russia, having the leading role in gross grain harvest improvement. The use of new adaptive varieties of winter common wheat in agriculture is the most realistic means of reducing the adverse effects of climate change ensuring a productivity rise and improving the technological properties of grain and flour. The developed winter wheat varieties should combine potential productivity and resistance to abiotic and biotic environmental factors through improved adaptability.Methods. The study was carried out in 2018–2022 on the fields of the research crop rotation of the FSBSI «ARC “Donskoy”», according to a green manure fallow due to the methods of SVT and a field trial.Results. The winter common wheat variety Zodiak can form a consistently high yield after various forecrops from 5.63 t/ha, when sown after sunflower to 10.23 t/ha when sown in green fallow. The variety formed the maximum productivity of 11.14 t/ha when sown in weed free fallow in 2018 and 2022. The study of the physicochemical properties of grain showed that the quality of grain and flour in the Zodiac variety corresponds to valuable wheat varieties. The protein percentage is 14.15%, gluten is 28.5%, the gluten quality corresponds to group I (IDK is 67 bp), the alveograph index is 255 f. a., the volume yield per 100 g of flour is 700 cm³, the baking assessment is 4.4 points, valorimetric estimation is 79 bp, SDS-sedimentation is 59 ml. The new winter common wheat variety Zodiak has been included in the State Register of Breeding Achievements since 2022 and recommended for cultivation in the 6th North Caucasus region.

Extensive microphytobenthos mats of invasive Vaucheria aff. compacta and abiotic environmental factors influencing its abundance in Adventfjorden tidal flat, Svalbard

Extensive microphytobenthos mats of invasive Vaucheria aff. compacta and abiotic environmental factors influencing its abundance in Adventfjorden tidal flat, Svalbard

COMPARATIVE MORPHOLOGICAL AND BIOLOGICAL CHARACTERISTICS OF INULA HELENIUM IN NATURAL CONDITIONS

Green mass and rhizomes of Inula helenium L. are valuable raw materials of great practical importance as a promising source of BAS (biologically active substances). An analysis of plants’ morphological and biological parameters in natural populations makes it possible to determine the yield and, when harvesting raw materials, focus on cenopopulations with an increased phytomass of inflorescences. Assessing the dynamics of the formation of the aboveground phytomass, indicators of photosynthetic activity, the productivity of the aboveground mass, and seed productivity of I. helenium under natural conditions also make it possible to determine the influence of abiotic and biotic environmental factors. The studies were carried out in the laboratory of the Department of Biotechnology and Standardization of the Faculty of Biotechnology of the FSBEI HE “Mountain State Agrarian University” in medium samples of I. helenium, selected in natural cenopopulations of the Republic of North Ossetia - Alania at altitudes of 615 - 847 m above sea level in the plant association of a cereal-forb meadow. In the course of the study, morphological and biological indicators were determined. The authors found that the weight of the rhizome with roots decreases along the vertical profile. Inula helenium in cenopopulations grow at different heights from 127 to 220 cm and form an average of 230-390 g of rhizomes with roots. Individuals of Inula helenium are characterised by the formation of 24 - 26 inflorescences on average on one shoot, each giving 625 - 1015 pcs seeds from 1 basket. The authors took samples of elecampane high close to the villages Surkh-Digora and Chikola North Ossetia - Alania. These samples are characterised by a high weight of 1000 seeds (1834.78 - 1923.24 mg) and a basket diameter (6.98 - 7.29 cm).

BIOLOGICAL CONTROL OF RASPBERRY SPUR BLIGHT CAUSED BY <i> DIDYMELLA APPLANATA </i> USING A MIXTURE OF MICROBIAL AGENTS

The article presents the results of three-year field trials of the mixed experimental bio preparation Phytop 26.82, consisting of the bacteria Bacillus amyloliquefaciens RCIM (All-Russian Collection of Industrial Microorganisms) B 10642, Bacillus licheniformis RCIM (All-Russian Collection of Industrial Microorganisms) B 10562, Bacillus subtilis RCIM (All-Russian Collection of Industrial Microorganisms) Microorganisms) B 10641, nematophagous fungi Arthrobotrys oligospora RCIM (All-Russian Collection of Industrial Microorganisms) F-1141 and Duddingtonia flagrans VKM F-2574, as well as the entomopathogenic fungus Beauveria bassiana, against the central raspberry disease - purple spot in the production plantations of the culture. The concentration of the mixture was 105 CFU/ml. As a comparison, we used the chemical fungicide Topaz, EC (emulsion concentrate) at 0.1% concentration. Previously, the authors evaluated the effect of this microbial mixture on the pathogen Didymella applanata in laboratory conditions, which was the basis of field trials. It was found that when one-year-old raspberry shoots were affected by purple spotting, the treatment of vegetative plants reduced the development of the disease by almost three times for more than a month after applying the microbial mixture. Furthermore, the prevalence of the disease decreased by two times or more relative to the control. The biological efficiency of the experimental bio preparation Phytop 26.82 reached 72.7%, comparable to the Topaz chemical fungicide. This mixed microbiological preparation is promising as an environmentally friendly means of protecting raspberries from purple spotting while suppressing other potential diseases and pests on this crop and reducing the undesirable influence of abiotic environmental factors.