|
|
Identification of RNA elements in fungi
PÍCHALOVÁ, Barbora
Nowadays, the focus of fungus, mycovirus and environmental interactions has expanded. The kingdom of Fungi includes ecologically and economically important species of fungi that are pathogenic or symbiotic or can occur in the soil as mycorrhizal and endophytic fungi. Despite their ecological significance, biomedical and industrial importance, phylogenomic studies of Fungi and their viruses are lacking. To understand the basic interactions between mycoviruses and their fungal hosts, the study of the biological properties, distribution and transmission is required. This study aims to identify different species of fungi and determine the interaction between fungus and virus. Samples collected in the Czech Republic during 2020 and 2021 were used for diversity research and molecular genetic methods were chosen for their detection and identification. DNA was isolated using CTAB-PVP, the DNA segment was amplified and phylogenetically analyzed using the sequences of internal transcribed spacers (ITS), the translation elongation factor (TEF) 1-alpha gene and the beta-tubulin gene. Based on the sequences, a phylogenetic tree was created for the samples according to the genetic similarity between the individual genera. The method of dsRNA isolation using phenol-chloroform and cellulose was used for the detection of mycoviruses.
|
|
|
Studium diversity a rozšíření virů entomopatogenní houby \nl{}\kur{Beauveria bassiana} v České republice
VANĚČEK, Petr
Mycoviruses are viruses that infect and replicate in fungal cells, but unlike most known viruses of plants and animals, they exceptionally produce deleterious effects on their host. Nonetheless, the last discoveries showed that some mycoviruses can decrease the virulence of their phytopathogenic fungal hosts, making them very attractive for their possible use as biological control agents. Most mycoviruses have dsRNA genomes and are widespread in all major taxa of fungi. Beauveria bassiana is one of the most studied species of entomopathogenic fungi; it has a cosmopolitan distribution and is used as biocontroller against invertebrates in agriculture. In the present work, a collection of 137 isolates of B. bassiana obtained at different locations and from different habitats in the Czech Republic was analysed. These isolates were analysed for the presence of dsRNA elements indicative of viral infections. The results revealed a high prevalence of viral infections in Czech B. bassiana isolates, with 22.6% of the isolates containing dsRNA elements with viral characteristics. Obtained dsRNA electropherotypes showed that virus diversity in infected isolates was high and that mixed virus infections occurred among them. Based on the characteristics of the electrophoretic band patterns, it could be hypothesized that B. bassiana isolates collected in the Czech Republic could harbour members of the viral families Totiviridae, Partitiviridae, Chrysoviridae and Hypoviridae.
|
|
|
Occurrence of putative dsRNA mycoviruses in Ash Dieback Causal Agent
Čermáková, Vendula
Thanks to environmental changes, globalization, long distance trade and plant transport, invasive organisms have become a major threat for world biodiversity and ecosystem services. Over the last 20 years, common European ash trees (Fraxinus excelsior L., Fraxinus angustifolia Vahl. etc.) have been subjected to heavy dieback and mortality because of the introduction and spread of the ascomycetous fungal pathogen Hymenoscyphus pseudoalbidus Queloz (syn. Chalara fraxinea Kowalski). Once the disease is established, its management is hardly possible. Therefore, one of the main objectives of European researchers is to find effective and respectful control methods, such as biological control. The discovery of viruses which reduce the virulence of the chestnut blight fungus Cryphonecria parasitica (Murr.) Barr., has intensively stimulated the research of fungal viruses as potential biological control agents (BCA). The occurrence of putative dsRNA particles in the decaying fungus H. pseudoalbidus was investigated as an important indicator of the mycoviruses' presence. In total, 106 samples of this pathogen were obtained from eight different European countries. According to the results, dsRNA segments were confirmed in 32.1 % of examined samples (two similarly sized at 2--2.5 kb and a third one of approximately 5 kb). Statistical results have revealed no significant relation between the presence of dsRNA and growth rate, colour or any other characteristic of the mycelium.
|
guest ::
