Home – Home – Jornals – Contemporary Problems of Ecology 2023 number 4

The study of alkali-resistant fungi was carried out for the first time on the coast of saline lakes in the south of the Trans-Baikal region on the territory of the Daursky Biosphere Reserve (lakes Zun-Torey, Khangei). Indicated changes in the structure of the community of alkali-resistant ascomycetes depended on local conditions. The coast of Khangei was devoid of halophites, but with a high content of Artemia eggs and was characterized by the absolute dominance of the alkaliphilic ascomycete Sodiomyces alkalinus (100 % occurrence) and Emericellopsis alkalina (80 %), with a minimum diversity of other fungi. S. alkalinus predominated (100 %) on the coast of Lake Zun-Torey in damp places without plants. Dark-colored fungi from Dothideomycetes (Alternaria, Neocamarosporium, etc.) predominated in the alkaline soil samples of this lake not far from the halophites, the occurrence of E. alkalina was 60 %, and S. alkalinus was not found here, but the high occurrence was shown for the other species from Plectosphaerellaceae (Chordomyces, Gibellulopsis). The distribution, substrate preferences, and functional roles of alkaliphilic and alkalitolerant fungi in extreme natural habitats with soda salinity are discussed in this paper.

The biodiversity of wood-destroying fungi on leguminous woody plants (LWP) growing in the Middle Urals has been studied for the first time. In the model region – Sverdlovsk province, from 2002 to 2022, there are 136 species of wood-destroying fungi were collected: 127 species of Basidiomycota and 9 species of Ascomycota. Fungi develop on 12 out of 20 species of LWP. The largest number of fungal species was found on the alien Caragana arborescens (115 species / 84.5 % of the total number of species), while on Caragana decorticans, C. ussuriensis, Laburnum alpinum two each, and one on Genista florida. 122 species of fungi were found on nine alien species of the LWP, which is 4.1 times more than on three native species. The largest number of substrate-specific fungal species develops on C. arborescens (85/62.5 %), while four on Chamaecytisus ruthenicus (2.9 %), three on Maackia amurensis (2.2 %), two each on Genista tinctoria and Robinia pseudoacacia (1.5 %), and one species on Caragana ussuriensis (0.7 %). Nectria cinnabarina develops on seven species of LWP, on six species – Xylodon sambuci, on four – Peniophora cinerea and Schizophyllum commune. In contrast, 71.3 % of fungal species were found on one LWP species, and 27.2 % of species are characterized by a single find. For the first time for Sverdlovsk province, 14 fungal species are indicated, of which 86 % were found in the parks of Ekaterinburg city, tree-lines along the roads, but only 14 % in natural conditions.

In order to reveal the latitudinal-zonal specificity for the distribution of species richness of the LWP associated mycobiota, we use Aphyllophoroids as the largest group of fungi among all analyzed (75 % of species), and Caragana arborescens, or Siberian pea tree, is the richest plant substrate. Changes in the fungal diversity were studied along a meridional transect stretching for 800 km. along 60° E, from the middle boreal subzone of Sverdlovsk province to the steppes of Chelyabinsk province (Russia) and Kostanay province (Kazakhstan). In each of the 5 vegetation zones/subzones, as well as in Ekaterinburg city, six sites were studied, the area of which varies from 0.9 to 6.8 ha. The aboveground phytomass of C. arborescens is maximal in the forest-steppe (8.9–11.7 t/ha), and minimal at the edges of transect (2.4–5.8 t/ha).A positive correlation was found between the aboveground plant phytomass and the species richness of mycobiota, while there was no correlation with climatic parameters. In Ekaterinburg city, where the Siberian pea tree phytomass is two times lower than in the forest-steppe, but the species richness of mycobiota is similar to the forest-steppe, is out of this pattern. A similar result was obtained for α-diversity (average number of fungal species on the sites and Shannon index) of mycobiota: an increase in indicators from the middle boreal subzone to the forest-steppe and a decrease in the steppe. The Whittaker and Czekanowski – Sørensen indices (β-diversity) increase towards the steppe, which is due to a strong relationship with the mean annual temperature and precipitation. A range of fungal species gravitating towards northern, southern and urbanized conditions has been revealed. In the north of transect, local species of fungi predominate, while in the south and in Ekaterinburg city, the role of biogeographically distant (alien) taxa is high. In this regard, the species composition of Siberian pea tree’s mycobiota is divided into two clusters – northern (boreal) and southern (nemoral-steppe) including Ekaterinburg city. To the south, species richness of pathogenic fungi increases, but this parameter does not correlate with the C. arborescens phytomass. In plantings of invasive Siberian pea tree, species richness of Poroid fungi is similar to Corticioid fungi at the local and regional level, which differs significantly from natural conditions. A high level of pathogenic fungi was also revealed compared to natural conditions. The results obtained can be used to optimize the concept development of Greenway planning in Ekaterinburg city and can help prevent a number of environmental problems arising after the “rapid” implementation of the strategy for the city development and surrounding areas.

Changes in the taxonomic structure of the fungal community during the processing of cow manure with straw using Eisenia fetida worms were studied using fundamentally different methods - cultural and metabarkoding (by amplification and high-performance sequencing of ITS2 rDNA). Significantly more fungal taxa have been identified in substrates and vermicompost by application of metabarkoding than by plating method (66 and 33 species, respectively). Single species were identified simultaneously by both methods. The method of metabarcoding revealed OTE of Ascomycota, Basidiomycota, Mortierellomycota, Chytridiomycota, Glomeromycota, Basidiobolomycota, Rozellomycota, Aphelidiomycota, fungi from Ascomycota, Basidiomycota, Mucoromycota were isolated by culture method. The species richness of the community decreased during the first 10-20 days of substrate processing, then grew and reached maximum values in the vermicompost (60 days). Both methods showed the dominance of ascomycetes at all stages of transformation of sunstrates by E. fetida. Metabarcoding showed the dominance of sordariomycetes of the order Sordariales (48-53 %), mainly Zopfiella spp., fungi of the orders Pezizales, Microascales, Hypocreales, Pleosporales, Chaetothyriales, Onygenales, Eurotiales had the representation at the level of several percents. The increase of the portion of Chytridiomycota in the community (from 1,1 to 3.2 %) was observed during vermicomposting. At the same time, the representation of fungi of Mortierellomycota (5.7 to 1,5 %) of genus Mortierella and Basidiomycota (from 8 and 21 to 3 %) decreased with an increase in their diversity. Among the basidiomycetes, Coprinellus marculentus, Coprinellus subdisseminatus, Coprinus annuloporus, Occultifur sp prevailed. According to the plating method, ascomycetes also prevailed during waste processing and in the vermicompost, but it were other species - Diplodascus geotrichum, genera Penicillium, Aspergillus, Talaromyces, Trichoderma, Fusarium, mucoromycetes of the genus Mucor and basidiomycetes - Filobasidium wieringae. Fungi capable of decomposition of various polymer compounds in waste, active destructors of lignocellulose have been identified. Coprophiles, keratinophiles, thermophilic and thermotolerant species, representatives of the genera Trichoderma, Penicillium, capable of determining the suppressive properties of vermicompost to phytopathogens and human pathogens were found. The differences in mycobiota during composting and vermicomposting of various wastes are considered.

The interaction in the system “epiphytic microorganisms - host plant-pathogen” was considered on the example of Scotch pine (Pinus sylvestris L.) seedlings which artificially infected with the facultative saprotroph Lophodermium seditiosum Minter, Staley & Millar. At the same time, the change of quantity of the epiphytic microorganisms, the composition and concentration of volatile compounds and the morphological parameters of pine in different variants of the experiment were studied. The influence of two factors on the studied characteristics was considered: L. seditiosum infection and the introduction of mycocompost into the soil. Classical phytopathological and microbiological methods were used. Volatile compounds were studied using chromato-mass spectrometry, phytoncide activity was studied using the Tokin method adapted to our conditions. At the stage of ascospore germination, an increase in the amount of volatile components released by the affected needles and a decrease in the number of those released by the roots of infected plants were noted. Against the background of changes in the composition of volatile compounds, an increase in the phytoncide activity of the leaf and root systems of plants with signs of the disease was found compared to specimens without signs of damage. This is also evidenced by the results of microbiological cultures: in the variants with infection, compared with the control, a significant decrease in the number of epiphytic microorganisms was noted. A significant increase in the mass of needles was noted in the variants with infection and with the adding of mycocompost, confirmed by ANOVA analysis. Registered correspond to Selye’s adaptive syndrome (activation of physiological processes at an early stage of adverse effects, followed by exhaustion of the body if the load continues).

The ability to determine the spatial distribution of rare fungal species is critical to understanding the environmental factors that affect them. Maximum entropy (MaxEnt) spatial distribution modeling solves this problem by allowing inferences about the distribution of species in a gradient of environmental factors based on occurrence data. To identify patterns of spatial distribution based on objective data, models of the potential geographical distribution of the rare polyporoid fungus of Picipes rhizophilus under current conditions (~1950-2000) and with predicted future climate changes (2100 AD) on a global scale were created. The species Picipes rhizophilus can develop in steppe habitats of both plains and mountains. Most of the known habitats of the species are found in the ecoregions that make up the Temperate grasslands, savannas and shrublands, Mediterranean Forests, woodlands and scrubs, and Deserts and xeric shrublands biomes. The species is not associated with forest biomes, but it can be represented in habitats located on their territory, subject to the processes of climate aridization and desertification. The species Picipes rhizophilus can develop in steppe habitats of both plains and mountains. Modeling the potential distribution of the species under the selected climatic scenario showed the dynamics of changes in its range. The species-friendly climate area will increase in the North American continent, while there will be no significant changes in Europe and adjacent areas of Africa. In the most favorable territory for the species, located in the basin of the Western Manych River, conditions will become less favorable. In the Asian part, there will be a local shift in the areas of potential distribution.

Data on the dynamics of rust fungi are presented on the example of the Skadovsky Zvenigorod Biological Station of Lomonosov Moscow State University. The survey was carried out by the route method in years 2011-2019 and 2021 during vegetative season. 81 species of rust fungi were recorded on the territory of the biological station, the number of species detected during one year varies from 36 to 56. The number of species detected per year shows a significant correlation (r = 0.76) with the G index calculated from temperature and rainfall in June and August. During each season there is a change in the dominant stages of rust fungi. Species with aeciospores (I) are more common in June, species with urediniospores (II) are more common in July, and species with teliospores (III)predominate in August. The number of species detected in stage II per month is mainly determined by the number of species identified in the previous month in stage I (r = 0.61). Similarly, the number of species detected in stage III in a month is predominantly determined by the number of species detected in the previous month in stage II (r = 0.85). The revealed dependencies correspond to the biology of the Pucciniales.

The taxonomic diversity of epiphytic myxomycetes on living woody plants in the arboretum of the Central Siberian Botanical Garden SB RAS was studied. The regularity of the distribution community of epiphytic myxomycetes by trunk height has been established. All samples of myxomycetes were obtained by cultivation moist chambers in Petri dishes in the laboratory. Bark sampling from live woody plants was carried out at the height of the trunks from 0 to 15 meters from the soil level. Nine species of deciduous woody introduced plants participated in the experiment: Fraxinus pennsylvanica, Prunus maackii, Populus alba, Salix alba, S. pentandra, S. triandra, Sorbus aucuparia, Tilia cordata, Junglans mandshuria. Fifty-one species of myxomycetes have been identified. The species composition of myxomycetes on the studied woody plants differs significantly from that on native tree species growing on the territory of the botanical garden. Two species have been identified as new to science from the genera Arcyria and Trichia, three species are new to Russia (Didymium clavodecus, D. ovoideum, D. synsporon), eighteen species are new to the Novosibirsk region. The change in the taxonomic composition of myxomycetes community′s correlates with the height from the soil surface. Representatives of the genus Perichaena are found at all altitudes, but the greatest species diversity is noted in the basal part. There are 7 species noted here, while the species of the genus Didymium have the maximum species diversity (6 species) at an altitude of 5 meters, including 3 species new to Russia, noted only at this altitude. The distribution of the number of collected samples by height showed that the bark of living woody plants is most abundantly populated at a height of 5 meters (72 samples) and in the basal part (50 samples).

Ecological and genetic characteristics of the phoma-like fungus Calophoma complanata were defined. C. complanata is a potential bioherbicide of the giant hogweed. An ecological analysis of the C. complanata sample collection sites showed this pathogen is found where the humidity is high, and the temperature is a lower than at other sites of phoma-like micromycetes. The growing degree days >10 ℃ (GDD) of the distribution of the species varies between 106.0 (Shetland) and 911.5 (Lublin, Poland) with rather low average of 570. The minimum and maximum Selyaninov hydrothermal coefficient on the boundary of the species area are 3.26 and 1.31, respectively, with the average of 1.9. The species area is characterized by long photoperiods. Classical morphological, histochemical, and molecular methods for founding C. complanata MF‑32.121 in plants were carried out. It is shown that this species, depending on the conditions, can be able to cause the Sosnowsky's hogweed disease, or turns to the endophytic lifestyle. We believe that this is one of the mechanisms that allow the pathogen to survive in harsh natural conditions. The obtained data allow to predict the effectiveness of mycoherbicides depending on environmental conditions, to assess the long-term risks associated with its application and to reveal the spectrum of non-target biological activities.

Based on the culture method and high-performance sequencing of the ITS2 rDNA site, the number of colony-forming units (CFU), taxonomic structure and species richness of fungal communities in the bottom ground of Lake Baikal from depths from 9 to 178 m were determined. 215 species of 138 genera of 50 orders of 22 classes of 6 divisions - Ascomycota, Basidiomycota, Mucoromycota, Mortierellomycota, Chytridiomycota, Glomeromycota have been identified. Only DNA barcoding allowed to detect representatives of the Phyla of Chytridiomycota, Glomeromycota and Rozellomycota. The cultural method and high-performance sequencing of the ITS2 rDNA site in the soil revealed 77 and 146 species, respectively, and only 8 species were established by both approaches. Most of the nucleotide sequences have not been identified to the level of families and species. There are representatives of various ecological and trophic groups - saprotrophs, pathogens, symbiotrophs in the mycobiota of the bottom grounds. These are mainly psychrotolerant organisms, among them there are facultative anaerobic species. Changes in the taxonomic structure of fungal communities depending on the depth and species, and able to function in soils, have been established. These are, in particular, Pseudeurotium bakeri, Pseudeurotium hygrophilum, Pseudogymnoascus pannorum, Pseudogymnoascus roseus, Trichoderma hamatum, Trichoderma harzianum, Trichoderma lixii, Trichoderma polysporum, Penicillium glandicola, Penicillium swiecickii, species of the genera Rhizophydium, Fusarium, Daldinia Mortierella, Coniochaeta, Cystobasidium, Mrakia, Rhodothorula, Solicoccozyma and a number of others. A collection of fungal strains isolated from the bottom soils of Lake Baikal has been created.

For the first time, the results of studying the long-term dynamics of the phytopathological state of alien tree and shrub plants (hereinafter as ATSP) in Ekaterinburg city (Russia, Ural) are presented. In connection with the active implementation of numerous landscaping programs, including the concept of the Greenway planning of Ekaterinburg city, over the past twenty years, a large number of ATSP seedlings have arrived in the city, which contributes to the penetration of many previously unknown species of alien and pathogenic fungi into the Urals, the number of which increases exponentially. On alien woody substrates, many species of local saprotrophic fungi exhibit pathogenic properties, which also contribute to a sharp increase in the pathogenic activity of urban mycobiota. A number of invasive fungal species cause mass diseases of woody plants and expand their trophic spectrum. Some invasive fungal species are expanding their invasive range into the natural forests. A list of ATSP species resistant to local and alien diseases, which are recommended for greening Ekaterinburg, is given. The applicability of the "sentinel plantations" technique for the early detection and localization of alien phytopathogens is discussed. Recommendations are given for the creation of a four-stage system of phytopathological monitoring of green urban spaces, which will contribute to the protection against penetration and the rapid detection of alien pathogenic fungi before diseases outbreaks.

At present, the taxonomy of fusarioid fungi has changed significantly due to the clarification of their taxonomic status by molecular genetic methods. This led to the emergence of new species / genera and the abolition of old ones. Data on the diversity and distribution of Fusarium species do not always correspond to modern taxonomy and require careful revision. In this work, we systematized long-term data on the species composition and specialization of fusarioid fungi associated with woody plants in Russia (Far East, Siberia, Northwestern region, Crimea). Molecular genetic identification of 53 isolates previously identified as Fusarium spp. was carried out. Using morphological characters, phylogenetic analysis, and ecological features, five Fusarium species complexes have been identified. 11 Fusarium species have been identified (F. acuminatum, F. avenaceum, F. equiseti, F. oxysporum, F. redolens, F. reticulatum, F. sambucinum, F. sporotrichioides, F. torulosum, F. tricinctum, F. venenatum) and 1 closely related species of the genus Neocosmospora (N. solani). On woody plants, the Fusarium tricinctum species complex is represented by the largest number of species: F. acuminatum, F. avenaceum, F. reticulatum, F. torulosum and F. tricinctum. The maximum number of isolates (17) belong to the F. avenaceum associated with various plants throughout the study area. In forest nurseries (Central and Southern Siberia) on juvenile plants with symptoms of mycosis, seven species of Fusarium and N. solani were identified. F. oxysporum, F. equiseti and N. solani were found only on seedlings of conifers in the first year of vegetation. In forest and park stands, where fusarioid fungi are predominantly saprotrophs and endophytes, nine Fusarium species were found, of which F. tricinctum, F. torulosum, F. venenatum and F. reticulatum were not isolated from pathological and seed material in forest nurseries.

On the example of spruce forests of the European taiga of Russia, the most important functional positions of wood-destroying fungi (DRFs) in the genesis of forest communities are described. In spruce forests, the age structures of forest stands, the extent of damage to forests by the DRG of the biotrophic complex, the volume of tree waste, and the participation of fungi of the xylotrophic complex in the decomposition of deadwood biomass by stages of decomposition were studied. The graphic version shows the structure of the process of formation of the biomass balance of the indigenous taiga spruce forest, based on differences in the time periods of accumulation and decomposition of the biomass of woody fractions of indigenous sustainable spruce forests. DRGs perform the task of coordinating the processes of accumulation and decomposition of forest biomass, maintaining its balance in the dynamics of the forest community to a state of optimal sustainability. The participation of wood-destroying fungi in the formation of structures of sustainable spruce forest formations should be considered as the main paradigm of their functional tasks in forest communities.