Phytopathogenic Micromycetes Research Articles

EFFECTS OF BIOLOGICALS AND PLANT GROWTH REGULATORS ON THE SOWING QUALITY OF EGGPLANT SEEDS

Purpose. To investigate effects of biologicals with fungicidal and stimulating activities and natural and synthetic plant growth regulators on the sowing quality of seeds of various eggplant hybrids. Methods. Laboratory methods in compliance with DSTU 4138:2002. Results. Soaking of seeds of various eggplant hybrids in Phytocid, Mycosan-B, PhytoHelp, MycoHelp, Azotophyt, Vympel, Humisol, Ivin, and Emistim C solutions had positive effects on the sowing quality of seed: the germination energy increased on average by 1–34% and the laboratory germinability – by 2–28%. Regardless of the hybrid, soaking of seeds in Phytocid, PhytoHelp, and MycoHelp solutions significantly increased the germination energy by 34.2%, 32.5%, and 32.5%, respectively, compared to the control and the laboratory germinability of seeds by 27.6%, 27, 4% and 27.4%, respectively. When plant growth regulators Azotophyt, Ivin, and Emistim C were applied, the germination energy and laboratory germinability increased on average by 18–28% and 15–24%, respectively, compared to the control. With Mycosan-B, Vympel, and Humisol, the germinability and germination energy of seeds did not differ from the control levels. Soaking of eggplant seeds in solutions of the studied formulations positively affected the seedling length: there was on average a 1.24- to 1.94-fold elongation of seedlings. It was found that seeds of the investigated eggplant hybrids were contaminated with phytopathogenic micromycetes and, depending on damage degree, the hybrids were ranked in the following order: 'Sapfir'> 'Sharapova', 'Samurai' > 'Leire' > 'Night Lady', 'Fabina' > 'Destan'. Mycosan-B, Vympel, and Humisol were little effective (2.5–6.3%) against phytopathogens in comparison with the other formulations. Phytocid, PhytoHelp, and MycoHelp exerted potent fungicidal effects, which varied on different hybrids: 42.5–68.8%, 30.0–65.6%, and 32.5–65.6%, respectively. The fungicidal effectiveness of Ivin and Emistim C was 20.3% and 18.8%, respectively. Conclusions. Soaking of eggplant seeds in solutions of biologicals (Phytocid, PhytoHelp, and MycoHelp) and synthetic and natural plant growth regulators (Ivin and Emistim C, respectively) was shown to beneficially affect the sowing quality of seeds and suppress fungal phytopathogens. The greatest stimulatory effects of Phytocid, PhytoHelp, MycoHelp, Ivin, and Emistim C on the sowing quality of seeds were seen on hybs. 'Destan', 'Leire', and 'Fabina'. 51–58% suppression of phytopathogens was achieved when eggplant seeds were soaked in Phytocid, PhytoHelp, and MycoHelp; Ivin and Emistim C resulted in 19–20% suppression. The greatest suppression of phytopathogens on eggplant seeds was observed on hybs. 'Destan', 'Leire', 'Night Lady', and 'Fabina'.

Monitoring of main tomato (Solánum lycopérsicum L.) diseases and methods of microbiological control of phytopathogens

The article highlights the main diseases of tomato plants caused by phytopathogenic microorganisms that cause great damage in many countries of the world, including Ukraine. It has been analyzed that phytopathogenic micromycetes that parasitize tomato plants cause huge losses in agricultural production, reducing the quality of products, and also release toxins that cause poisoning and numerous serious diseases that affect humans and animals that consume this product. It has been established that the most common tomato diseases caused by phytopathogenic fungi are late blight, alternaria, septoria, gray rot, spotted wilt virus, and bacterial tomato cancer. Microbiological means of control were analyzed as an alternative to chemical fungicides, which are considered safe methods in modern agriculture. They stimulate the defense mechanisms of plants, acting as inducers of plant resistance or as means of biological control. It was found that one of the common biological preparations in the fight against diseases and improving the growth of tomato culture are preparations containing Trichoderma spp. They are widely used as biofungicides against the pathogens Botrytis cinerea, Fusarium oxysporum, Rhizoctonia solani and Sclerotium rolfsii. The study of Mexican scientists on the testing of various isolates of the genus Trichoderma spp. Chinese scientists identified a strain of Pseudomonas aeruginosa (CQ-4) that can effectively control the spread of gray rot disease and identified bacteria of the genus Bacillus subtilis, which are characterized by notable antagonistic activity against a wide range of phytopathogenic bacteria and micromycetes and are a factor in biological control. Also, scientists from Egypt who conducted experiments on two endophytic fungi, namely Curvularia lunata and Nigrospora sphaerica, where their antagonistic action against phytopathogenic fungi and their ability to produce an important growth hormone and provide some necessary nutrients for plant growth were evaluated. A number of investigated antagonist strains are the basis or promising for the production of microbial preparations for controlling phytopathogens in agroecosystems and increasing the yield of tomato plants.

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

The aim of the study is to find the strongest soil microorganisms from autochthonous microbial communities of Central Siberia against phytopathogenic micromycetes Alternaria tenuissima. The object of the study is autochthonous soil bacteria isolated from the soils of the Krasnoyarsk forest-steppe in the Sukhobuzimsky District. Soil samples were taken from under spring wheat Novosibirskaya 15 and from under perennial grasses. The soil cover is represented by ordinary leached chernozem. Ammonium nitrate was used (34.7 kg/ha active ingredient). The climatic conditions are moderately dry and continental. The studies were carried out in 2022–2023. Antagonistic activity was measured on the GRM Saburo. With a general growth of the test culture and soil bacteria, the strongest antagonists were found in the suppression zone of Alternaria tenuissima. The identification of the most powerful bacterial antagonists in reducing the intensity and prevalence of root rot was carried out using the method of artificial infection with 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 carried out 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 < 0.01) reduced the intensity and prevalence of this disease. The maxi-mum effect in reducing the intensity and prevalence of the disease was shown by isolates B2 and B4. Also, the studied bacterial strains showed a significant effect (p < 0.001) on the length of sprouts. The greatest increase in length in spring wheat sprouts was in the experimental variant with strain B2. This strain can be recommended not only for protection against Alternaria tenuissima, but also for stimuli-ting wheat growth.

Basic and additional ecological niches of soil phytopatogenes on spring wheat varieties in West Siberia

The elucidation of hydrothermal and temporal parameters of the realization of the main and additional ecological niches of jointly parasitizing widespread soil phytopathogenic micromycetes has theoretical and applied significance. The aim of the study was to identify the parameters of the implementation of the main and additional ecological niches by the dominant species of soil micromycetes on spring wheat (Bipolaris sorokiniana Sacc. Shoem., Fusarium poae (Peck.) Wollenw., F. oxysporum Schltdl.) in the system of underground and generative organs of spring wheat varieties. The objectives of the study included determining the level of realization of the main ecological niches by three dominant species of soil pathogenic micromycetes in the system of underground organs of spring wheat varieties in different phases of vegetation, as well as identifying the degree of realization by micromycetes of additional ecological niches in generative organs of spring wheat varieties and assessing the strength of the influence of varieties and conditions of the year on the size of ecological niches in underground and generative organs of plants. The study was conducted on 20 varieties of spring wheat in 2020–2022, in the northern forest-steppe of the Ob region according to generally accepted and author’s methods. It is shown that the soil micromycetes B. sorokiniana, Fusarium poae and F. oxysporum, parasitizing together on the underground and generative organs of spring wheat, have different hydrothermal and temporal parameters of the realization of the main and additional ecological niches. B. sorokiniana is a relatively thermophilic species, its parasitic activity is most successful in underground, especially straw organs, is realized in conditions of unstable humidification, F. poae is a moisture-loving micromycete that prefers underground, especially young organs of spring wheat plants, F. oxysporum is a drought-resistant species that tends to more mature plant organs. As for the generative organs of wheat, B. sorokiniana colonizes them by airborne droplets in humid conditions, keeping them confined to straw-like tissues, the correlation coefficient of B. sorokiniana infection of the ear rods and the SCC of August was equal to r = 0.812 ± 0.412. F. poae could reach ears by vessels, the degree of their colonization by this micromycete was small and practically did not depend on the weather conditions of the year and its representation in underground plant organs. F. oxysporum colonized ears of spring wheat by vessels, and the degree of its representation in pathocomplexes of generative organs closely correlated with its share in pathocomplexes of primary and secondary roots: r = 0.923 ± 0.146.

Taxonomic analysis of phytopathogenic micromycetes of landscape trees and shrubs (based on the example or Samarkand city)

The article provides information about phytopathogenic micromycetes of trees and shrubs common in the city of Samarkand. In the course of the research, it was established that 45 species of micromycete fungi are found in 32 plant species and are pathogenic. As a result of the analysis, it was established that 45 species of micromycete fungi belong to 3 divisions, 14 orders, 24 families and 28 genera. Herbarium data collected during the study were analyzed and it was found that 45 species of phytopathogenic micromycetes parasitize 32 species of host plants belonging to 28 genera and 21 families. The study identified 45 species of phytopathogenic micromycetes parasitizing 32 species of host plants. These 32 species of forage plants belong to 27 genera and 21 families, of which 21 species of trees and 11 species of shrubs were identified. Under the influence of fungal diseases caused by phytopathogenic micromycetes recorded in 32 species of ornamental trees and shrubs, the aesthetic properties of these plants decreased. Host plants were identified that were heavily infected with several species of phytopathogenic micromycetes.

Analysis of phytopathogenic micromycetes common in fruit trees and shrubs (the city of Samarkand as an example)

Analysis of phytopathogenic micromycetes common in fruit trees and shrubs (the city of Samarkand as an example)

MICROFLORA AND PLANT PATHOGENIC FUNGI AFFECTING BACTERIA IN GRAPE PLANTATIONS IN UZBEKISTAN

In the presented study, isolation of bacterial strains, viz., Pantoea agglomerans, Priestia megaterium and phytopathogenic micromycetes that cause damage and eventually death of grape crops, came from a 10 to 15-year-old vine plantation. A Pantoea agglomerans gram-negative bacillus facultative and anaerobic bacterium strain achieved isolation from grape plants, with its morphological characteristics studied. Bacterial strains with antifungal activities against phytopathogenic micromycetes succeeded in their identification. Bacterial isolates collected from the vines underwent screening for their growth properties. It was apparent that Pantoea agglomerans actively grew wheat coleoptiles by 2.6 mm and maize coleoptiles by 2.3 mm compared with the control. Observable evidence also showed that sorghum coleoptile actively grew by 1.7 mm compared with the control treatment by 2.9 mm. The 26 Aspergillus sp., 23 Penicillium sp., 25 Fusarium sp., 30 Alternaria sp., and five Curvularia sp. phytopathogenic micromycetes belonging to the genus were notable. Bacterial strains isolated from the vine showed the highest antifungal activity against micromycetes belonging to the genus Penicillium and reduced the radius of phytopathogenic growth to 47–54 mm. Compared with micromycetes belonging to the genus Fusarium, it was also apparent that the pathogen reduced the growth radius to 27–35 mm. Isolation of phytopathogenic micromycetes from the vine allows early detection and prevention of grape diseases. Based on these studies, the identification of antifungal activity of the bacterial strains isolated from the vine and the presence of phytohormones in the culture fluid indicated that it is an essential and environmentally friendly biological tool in the cultivation of grapes for human consumption.

PHYSIOLOGICAL AND BIOCHEMICAL PROPERTIES OF SOYBEAN CULTIVARS INFECTED WITH PHYTOPATHOGENIC FUNGI

An investigation on soybean (Glycine max L.) commenced at the experimental field of the Institute of Genetics and Plant Experimental Biology, Academy of Sciences, Republic of Uzbekistan. The purposive study aimed to determine the effects of Fusarium solani phytopathogenic micromycetes on the physiological and biochemical composition of five soybean cultivars, viz., Sochilmas, Genetic-1, Nafis, Tomaris, and Baraka. The results revealed in the budding and flowering stages, the soybean cultivar leaves infected with F. solani showed decreased amounts of chlorophyll a and b compared with the healthy plants (control). In the control comparison against the soybean variants with phytopathogenic micromycetes, some soybean cultivars showed enhanced contents of carotenoids in the leaves, and others revealed a decline in carotenoids to varying degrees. The peroxidase enzyme activity was higher in soybean cultivars Tomaris and Nafis artificially infected with F. solani than the other cultivars. It was evident that the peroxidase enzyme activity under the influence of F. solani in the leaves of studied soybean cultivars increased by 20.76%, 43.6%, and 35.4%, respectively, in Baraka, Tomaris and Nafis cultivars. Results further indicated that under the influence and stressful conditions of F. solani, the activity of the polyphenol oxidase enzyme enhanced by 84.1% and 117.1%, respectively, in soybean cultivars Tomaris and Nafis. The phenylalanine-ammonia-lyase enzyme activity was also higher in the said cultivars with F. solani infection compared with the control. The earlier situation confirmed that the soybean plant leaves’ physiological and biochemical parameters are closely associated with the phytopathogenic micromycetes

Формування фітопатогенного мікобіому на вегетативних органах рослин пшениці озимої

Cultivated plants, which are characterized by high resistance to phytopathogenic microorganisms, create significant selective pressure on their populations and select highly pathogenic and aggressive forms. Highly susceptible plants to such microorganisms ensure a rapid growth in the population of phytopathogenic micromycetes in agrocenoses. Cultivation of such plant groups on production crops leads to an increase in biological pollution of the agrosphere and a significant decrease in the level of biological safety. This requires increased use of chemical means of plant protection against diseases, which causes chemical pollution of agroecosystems and leads to a significant decrease in the quality of plant products through the accumulation of metabolic products of phytopathogenic microorganisms in it and a decrease in biological safety in agrocenoses. Therefore, the assessment and selection of winter wheat varieties as a factor in the regulation of the phytopathogenic mycobiome in agrocenoses is a highly relevant area of research that ensures the selection of ecologically safe varieties of cultivated plants. Cultivation of such varieties leads to a decrease in the level of biological pollution in agrocenoses and increases the quality and safety of plant products. It is known that biotic, abiotic and anthropogenic factors affect the formation of populations of microorganisms. Therefore, the formation of the mycobiome on the vegetative organs of winter wheat during the ontogenesis of plants under traditional and organic technologies was investigated. It has been proven that the meteorological conditions during the years of the study, namely: high air temperature and a significant amount of precipitation during the growing season, which was observed in 2021 and in the long dry years of 2020 and 2022, had a significant impact on the formation of the population of micromycetes in the agrocenosis of winter wheat. According to the results of our own research, the population density of micromycetes and the intensity of sporulation of mushroom species decreased during the phase of emergence into the tube using traditional cultivation technology. At the same time, during the earing phase, mushroom sporulation increases by 2–3 times. This can be explained by the homeostatic reaction of the population of micromycetes in the mycobiome of vegetative organs of winter wheat plants to the chemical pressure of applied pesticides, which can cause contamination of agrocenoses with infectious structures of pathogens and their toxic metabolites. At the same time, the population density of micromycetes, under organic cultivation technology, increased during the growing season from the tillering phase to the earing phase, depending on the soil and climatic conditions. Under the conditions of various winter wheat cultivation technologies, significant changes in the formation of micromycete populations were observed due to the influence of varietal characteristics of plants. A significantly lower frequency of occurrence of species and their intensity of sporulation was observed on the vegetative organs of the Skagen variety, compared to winter wheat plants of the Podolyanka variety. This testifies to the ability of physiological and biochemical substances of plants of various varieties of winter wheat to stimulate or restrain the development of micromycetes in the mycobiome of vegetative organs of the culture. Evaluation of the plant variety based on indicators of influence on the density, frequency of occurrence and intensity of sporulation of micromycetes will ensure a decrease in the level of biological pollution and an increase in the biosafety of plant raw materials.

Analysis of Physiological and Biochemical Characteristics of Local Soybean Varieties which were Artificially Damaged with Phytopathogenic Fungi

According to the analysis of the results of the amount of chlorophyll "a" and "b" in the leaves of local soybean varieties under the influence of phytopathogenic micromycetes during the budding period was found that the chlorophyll "a" and chlorophyll "b" index of all soybean varieties decreased compared to the control. This situation indicates that the amount of chlorophyll "a" and chlorophyll "b" in the leaves of soybean plants is related to the presence of phytopathogenic micromycetes. When studying the effect of micromycetes F. oxysporum on the content of chlorophyll "b" in soybean leaves, the least effect was found in varieties Tomaris and Genetik-1 (respectively, the difference from the control = -9.3 and -9.6), and the local variety Sochilmas had the strongest influence (respectively, it showed that the difference from the control = -56.6 and -61.1). When studying the effect of micromycetes A. alternata on the amount of chlorophyll "b" in soybean plant leaves, the variety Genetik-1 had the least effect (respectively, the difference from Control = -15.4 and -14.3), and the strongest effect was on varieties Nafis and Sochilmas (respectively differences from control = -41.6 and -38.2).

The main mechanisms of environmentalization of the agricultural production

Solving the issues of environmentalization of agricultural production is an extremely important task in a scientific and applied sense, namely: providing the population with food, preventing crop losses from harmful objects, and protecting the environment from excessive chemical loading. Accordingly, an alternative solution in overcoming the negative consequences of chemicalization of agricultural production and improving the quality of seed products is the use of environmentally safe plant protection measures. An important component of technologies for growing various crops is their protection against phytopathogenic microorganisms. After all, in the agrocenoses of agricultural crops, there is an accumulation of an infectious background of phytopathogenic micromycetes, among which species of the genera Penicillium, Aspergillus, Alternaria, and Fusarium predominate, which can cause outbreaks of many plant diseases (root rot, Alternaria, Fusarium, Phytophthora, Anthracnose, Cercosporosis). Phytotoxic metabolites of necrotrophic phytopathogenic fungi, which are able to accumulate in soil, seeds and plant residues, deserve special attention. Mycotoxins lead to a decrease in the yield and quality of grain, as well as the quality of food products, which negatively affects their ecological safety, and can cause poisoning of humans and animals.

Анализ современного состояния проблемы фузариоза колоса и зерна пшеницы в Российской Федерации

Abstract. The aim of the article was to study and summarize the information about modern aspects of fusarium ear and grain of wheat, strategically important crop in the Russian Federation. Scientific novelty. As a result of analysis of scientific literature data on fusarial ear blight, the following main factors (features) were identify that develop ideas about this branch of knowledge: the biology of pathogens, their ecological plasticity; the difficulty of visual identification of phytopathogenic micromycetes of the Fusarium genus; specific etiology and harmfulness of the disease; insufficient effectiveness of measures to protect crop. Methods. In the process of research, by using analytical and statistical methods, the collection, analysis and generalization of information on biological properties, intrapopulation variability, the ability to produce mycotoxins dangerous for humans and animals, and other properties of phytopathogens of the Fusarium genus were carried out. Results. The information about significant factors causing the spoiling of an agricultural crop was systematized, and the urgency of the problem of fusarium ear and grain of wheat in the Russian Federation was shown. From the analysis of the data obtained, it follows that to control the destructive disease of wheat, it is necessary to study in depth the characteristics of the pathogen, and carry out a set of protective measures with timely identification of the phytopathogen. The presence of unresolved issues causes the continuation of research on the development of genetic methods of fusarium pathogen indication, assessment of the species composition of fungi and methods of forecasting their epiphytotic distribution; fungicide preparations using modern achievements of biotechnology, including nanotechnology and chemical synthesis; instrumental base for monitoring wheat crops for seeding with fusarium pathogens.

POPULATION OF PHYTOPATHOGENIC MICROMYCETES IN THE RHIZOSPHERIC SOIL OF KENT VARIETY SOYBEAN PLANTS

Fertile lands and a favorable climate led to the rapid spread of soybean production in Ukraine. At the same time, there is an increase in the mass accumulation of phytopathogenic microorganisms in soybean agrocenoses [1, 2, 3]. This leads to the development of harmful diseases of soybean plants during the growing season and can intensively colonize the vegetative organs of the plant, the rhizosphere and seed material, which leads to a deterioration in the quality of the crop [4]. Biopreparations are one of the most powerful factors in the regulation of biotic relationships in agrocenoses, which allows solving the issue of ensuring balanced nutrition of plants and resistance to phytopathogenic micromycetes.

Formation of the phytopathogenic mycobiome of seeds of sunflower hybrids in the conditions of the Сentral Forest-Steppe of Ukraine

A high level of contamination of the seeds of sunflower plants with phytopathogenic micromycetes can lead to a significant decrease in the yield of this valuable crop, a decrease in the oiliness of the seeds, a deterioration of its sowing qualities, and an increase in the quantitative and qualitative losses of the crop during storage. As a result of the vital activity of microorganisms on plant seeds, both the sowing qualities of the seeds (germination energy, germination, viability and productivity) and food quality indicators are significantly reduced (the fatty acid composition changes, oiliness decreases and the acid number of the oil increases). Therefore, the goal of our work was to determine the number and spectrum of phytopathogenic micromycetes in the mycobiome of sunflower seeds in the conditions of the Central Forest-Steppe of Ukraine. According to the research results, it was found that the biological properties of Dushko and Oliver hybrids, in the conditions of traditional and organic cultivation technologies, can both suppress and stimulate the number of micromycetes in the seed mycobiome. The formation of the number of phytopathogenic micromycetes in the mycobiome of the seeds of Dushko and Oliver hybrids under the organic technology of growing sunflower plants was at the level of traditional technology and ranged from 5.0 to 5.5 thousand CFU/g in the fruit shell, and from 2.1 to 2.6 thousand CFU/g of dry seeds. The seed microbiome of the investigated sunflower hybrids is represented by micromycetes with phytopathogenic properties (A. alternata and F. oxysporum) and species capable of causing seed mold (Penicillium, Aspergillus), the frequency of which varies from 5 to 65%. Phytopathogenic fungi inhabiting the seeds of sunflower plants are a powerful factor in the biological pollution of agroecosystems and are capable of significantly reducing seed quality and nutritional quality indicators of seed production of sunflower plants.

Antifungal Activity and Effect of Plant-Associated Bacteria on Phenolic Synthesis of Quercus robur L.

Europe's forests, particularly in Ukraine, are highly vulnerable to climate change. The maintenance and improvement of forest health are high-priority issues, and various stakeholders have shown an interest in understanding and utilizing ecological interactions between trees and their associated microorganisms. Endophyte microbes can influence the health of trees either by directly interacting with the damaging agents or modulating host responses to infection. In the framework of this work, ten morphotypes of endophytic bacteria from the tissues of unripe acorns of Quercus robur L. were isolated. Based on the results of the sequenced 16S rRNA genes, four species of endophytic bacteria were identified: Bacillus amyloliquefaciens, Bacillus subtilis, Delftia acidovorans, and Lelliottia amnigena. Determining the activity of pectolytic enzymes showed that the isolates B. subtilis and B. amyloliquefaciens could not cause maceration of plant tissues. Screening for these isolates revealed their fungistatic effect against phytopathogenic micromycetes, namely Fusarium tricinctum, Botrytis cinerea, and Sclerotinia sclerotiorum. Inoculation of B. subtilis, B. amyloliquefaciens, and their complex in oak leaves, in contrast to phytopathogenic bacteria, contributed to the complete restoration of the epidermis at the sites of damage. The phytopathogenic bacteria Pectobacterium and Pseudomonas caused a 2.0 and 2.2 times increase in polyphenol concentration in the plants, respectively, while the ratio of antioxidant activity to total phenolic content decreased. Inoculation of Bacillus amyloliquefaciens and Bacillus subtilis isolates into oak leaf tissue were accompanied by a decrease in the total pool of phenolic compounds. The ratio of antioxidant activity to total phenolic content increased. This indicates a qualitative improvement in the overall balance of the oak leaf antioxidant system induced by potential PGPB. Thus, endophytic bacteria of the genus Bacillus isolated from the internal tissues of unripe oak acorns have the ability of growth biocontrol and spread of phytopathogens, indicating their promise for use as biopesticides.

Phytopathogenic Micromycetes of Vitis vinifera Grown in Uzbekistan

In the cultivation of grapes in Uzbekistan, phytopathogenic micromycetes cause dangerous diseases and cause the death of most of the crop. Therefore, it is important to identify the micromycetes that spread the disease from grapes. The article covers research aimed at studying micromycetes that spread disease in grapes grown in Uzbekistan. This makes it possible to grow ecologically clean products in viticulture and identify dangerous diseases in advance. The aim of our study was to study the microbiome of the soil of the grape growing area, infected young vines, leaves and fruits of grapes and to identify the phytopathogenic micromycetes that spread the disease. As part of our research, samples of infected branches, leaves, and fruits of “Kishmish” and “Rizamat” grape varieties grown in Urgut and Altyarik districts of Uzbekistan were brought. Phytopathogenic micromycetes were isolated from the samples. Cleaned 10 times with 3% hydrogen peroxide, alcohol and distilled water was grown meat-peptone agar (MPA), potatodextrose agar (PDA), Oat agar (ОА), Chapek nutrient media. Micromycete isolates belonging to the genera Fusarium, Alternaria, Penicillium and Aspergillus were detected in the soils of grape growing and in samples taken from infected grapes.

PHYTOPATHOGENIC MYCOBIOTA IN AGROCENOSES OF CULTURAL PLANTS IN THE CONDITIONS OF THE CENTRAL FOREST STEPPE OF UKRAINE

Intensive development of phytopathogenic micromycetes in the agrocenoses of cultivated plants leads to significant crop losses, deterioration of its quality and reduction of plant productivity. Phytopathogens are a powerful factor in biological pollution of agroecosystems. The purpose of our study is to determine the number and species composition of micromycetes on the leaves of sunflower plants of Dushko and Oliver hybrids and winter wheat of Podolyanka and Skagen varieties in the agrocenoses of the Central Forest Steppe of Ukraine. Studies of the mycobiome of the leaves of sunflower plants have shown that the number of micromycetes is significantly influenced by the biological features of the investigated sunflower hybrids and their cultivation technologies. It was established that the number of phytopathogenic micromycetes on the vegetative organs of the investigated hybrids under the organic technology of sunflower cultivation was at the level of the traditional technology and varied between 14.6 and 19.9 thousand CFU/g of dry leaf. The species composition of micromycetes on the leaves of sunflower plants was determined and it was established that the dominant fungi are the following genera: Aspergillus P. Micheli ex Haller, Alternaria Nees, Penicillium Link; Fr, Fusarium Link and Cladosporium Link. They were characterized by a different frequency of occurrence during the growing season, which ranged from 15 to 70%. According to the results of the research of the mycobiome of the leaves of winter wheat plants, it was established that the number of micromycetes on plant leaves ranged from 0.9 to 3.8 thousand CFU/g of dry leaf and significantly depended on the cultivation technology and biological characteristics of plants of different breeding origins. Metabolites of Podolyanka winter wheat plants under conditions of both traditional and organic growing technology stimulated the development of micromycetes in the mycobiome of vegetative organs of plants. Metabolites of Skagen winter wheat plants under conditions of different cultivation technologies restrained the development of micromycetes at an ecologically safe level. The species composition of micromycetes on the vegetative organs of winter wheat plants was determined, and it was established that under the conditions of traditional growing technology, the dominant micromycetes were the species F. oxysporum, F. graminearum, and B. sorokiniana with a frequency of occurrence of 55 to 70%. And in the conditions of organic cultivation technology - F. oxysporum and T.viride, the frequency of which was 50%. Micromycetes of these genera are toxin-producing species that contaminate agricultural crops with mycotoxins, which poses a danger to animal and human health.

Pathogenic mycobiome and quality indicators of soybean seed (Glycine max Moench) under growing in organic technologies

The number of colony-forming units (CFU) of micromycetes in soybean seeds of Suzirya and Kent varieties, created by Filazonite technology, was determined. A significant suppression of micromycetes was found in soybean seeds of Suzirya and Kent varieties compared to the control sample. It was established that the formation of CFU micromycetes on soybean seeds of the specified varieties is influenced by seed growing technologies and climatic conditions. Depending on these factors, the number of CFU micromycetes on soybean seeds of different varieties ranged from 0.2·104 CFU/g of seed to 1.5·104 CFU/g of seed, which is almost 2.5 times less than the amount in the control sample (from 0.8·104 CFU/g to 2.7·104 CFU/g of seeds). It was established that the species of phytopathogenic micromycetes belonging to the genera Alternaria, Fusarium, and Penicillium dominate in the soybean seeds of Suzirya and Kent varieties. They are factors of biological pollution of agrophytocenoses and reduction of biosafety of products. The changes in the quality indicators of the researched varieties of soybean seeds, grown under conditions of organic production using biological technologies, were determined. Based on the results of three-year research, it was established that the indicators of the content of protein and oil in the seeds of Kent and Suzirya varieties in all variants were higher than the normative indicators specified in DSTU 4964:2008. TU. SOY. At the same time, the indicator of the mass fraction of seed moisture did not exceed the permissible norms. It was established that the biochemical composition of soybean seeds had a certain influence on the genotypes of the varieties, as well as the types of soil and the climatic conditions of the growing technology. Depending on these factors, the content of protein in the soybean seeds of the studied varieties ranges from 37.5% to 41.11%, fat from 19.02% to 21.7%, and the mass fraction of moisture from 8.8% to 11.4%.

Biopreparations as an agro-ecological factor enhancement of biosafety in agrocenoses

The problem of environmentalization of agricultural production is extremely important in a scientific and applied sense, the main task of which is to provide the population with food products, prevent crop losses from harmful objects, and protect the environment from excessive chemical load. Accordingly, an alternative solution in overcoming the negative consequences of chemicalization of agricultural production and improving the quality of seed products is the use of environmentally safe plant protection measures. Protection against phytopathogenic microorganisms is an important component of technologies for growing various crops. After all, in soybean agrocenoses there is an accumulation of an infectious background of phytopathogenic micromycetes, among which species of the genus Penicillium, Aspergillus, Alternaria, and Fusarium predominate, which can cause outbreaks of many plant diseases (root rot, Alternaria, Fusarium, late blight, anthracnose, cercosporosis). Phytotoxic metabolites of necrotrophic phytopathogenic fungi, which are able to accumulate in soil, seeds and plant residues, deserve special attention. After all, mycotoxins lead to a decrease in the yield and quality of grain, as well as the quality of food products, which negatively affects their ecological safety, and this, in turn, can cause poisoning of humans and animals. The use of biofungicides is aimed at controlling diseases and reducing their harmful effects. Seed treatment leads to disinfection of seed material and protection of young plants from various infections. Therefore, the use of useful microorganisms, which are part of biological preparations, which effectively affect the processes of functioning of agroecosystems, is relevant.

The features of diagnostics of grain crop seeds intended for export

Russia occupies a leading position among the largest wheat producers and exporters. One of the key requirements for the biological safety of domestic grain products is the phytosanitary requirements of importing countries. The conformity of grain products with regard to phytopathogenic micromycetes is determined by their complete absence or the minimum content in the batch. When shipping exported products, it is necessary to carry out a phytosanitary estimation of a batch of plant products in a short time. In the current paper there has been estimated the effect of the proposed method of sample preparation of grain crop seeds on the quality of an isolated fungal pathogens’ DNA. The purpose of the study was to optimize the methods of sample preparation of grain products for the extraction of nucleic acids with further identification to reduce laboratory trials. The development of modern, reliable and low labor-consuming methods for diagnosing phytopathogens in plant products is of great urgency. In order to conduct the current research, wheat, barley and rye kernels were artificially inoculated with such fungal pathogens as Parastagonospora nodorum, the causative agent of Septoria leaf spot, and Alternaria infectoria, the causative agent of Alternaria leaf spot. The infection was carried out by soaking the kernels in a spore suspension followed by incubation. In order to assess infection, there were used the classical methods of mycology, as well as the patented E.Yu. Toropova’s method. The pathogens were identified by a classical PCR analysis using the target-specific primers. There has been given an assessment of the sensitivity of the proposed extraction method for each of the studied crops. The method allows identifying target objects even with a minimum number of infected kernels in the sample (1–5 infected seeds per 195–199 healthy ones). There were not identified any related pathogens, and there were no false-positive results during the conducted PCR analysis.