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A novel negative-stranded RNA mycovirus was isolated from the phytopathogenic fungus Fusarium sibiricum strain AH32. This virus, tentatively named Fusarium sibiricum coguvirus 1 (FsCV1), has a bipartite genome consisting of two RNA segments (RNA1 and RNA2). The negative-sense RNA1 is 6737 nt in length, encoding the RNA-dependent RNA polymerase (RdRp, p251) in the viral complementary (vc) strand. The ambisense RNA2 (1232 nt long) encodes two overlapping proteins: the nucleocapsid protein (NP, p38) in the vc strand and an unknown function protein (UFP, p36) in the viral (v) strand, different from the typical features of Bunyavirales members: the two open reading frames are separated by a long AU-rich intergenic region (IR). Phylogenetic analysis based on the RdRp demonstrated that FsCV1 belongs to the genus Coguvirus, family Phenuiviridae, order Bunyavirales. This is the first report of a coguvirus infecting a fungus.

Fusarium langsethiae is a suspected plant-pathogenic fungus causing cereal contamination with trichothecene mycotoxins. Here, we report the genome sequences of two F. langsethiae strains, MFG217701 (a prototroph) and MFG217702 (a biotin auxotroph), isolated from a grain of oat harvested in Russia.

International audience; Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. Previously (Geiser et al. 2013; Phytopathology 103:400-408. 2013), the Fusarium community voiced near unanimous support for a concept of Fusarium that represented a clade comprising all agriculturally and clinically important Fusarium species, including the F. solani Species Complex (FSSC). Subsequently, this concept was challenged by one research group (Lombard et al. 2015 Studies in Mycology 80: 189-245) who proposed dividing Fusarium into seven genera, including the FSSC as the genus Neocosmospora, with subsequent justification based on claims that the Geiser et al. (2013) concept of Fusarium is polyphyletic (Sandoval-Denis et al. 2018; Persoonia 41:109-129). Here we test this claim, and provide a phylogeny based on exonic nucleotide sequences of 19 orthologous protein-coding genes that strongly support the monophyly of Fusarium including the FSSC. We reassert the practical and scientific argument in support of a Fusarium that includes the FSSC and several other basal lineages, consistent with the longstanding use of this name among plant pathologists, medical mycologists, quarantine officials, regulatory agencies, students and researchers with a stake in its taxonomy. In recognition of this monophyly, 40 species recently described as Neocosmospora were recombined in Fusarium, and nine others were renamed Fusarium. Here the global Fusarium community voices strong support for the inclusion of the FSSC in Fusarium, as it remains the best scientific, nomenclatural and practical taxonomic option available.

Introduction. Barley can be infected with a broad variety of fungi, which can cause considerable loss of crop yield and reduce the quality of grain. Modern vision on the geographical and ecological distribution and biodiversity of micromycetes has been established by traditional, cultivation-based methods. However, more recently, molecular methods have shifted microbiological research to a new level, making it possible to investigate hidden taxonomical biodiversity. Study objects and methods. For this study, we determined the fungal biome on the surface and inside of barley grains using the traditional mycological method and the contemporary molecular method, which employed DNA metabarcoding based on NGS (nextgeneration sequencing) of the ITS2 region. We analyzed five cultivars that were collected in two subsequent crop seasons (2014, 2015). Results and discussion. DNA metabarcoding revealed 43 operational taxonomic units, while 17 taxa of genus or species level were recovered by the traditional method. DNA metabarcoding revealed several minor species and one predominant, presumably plantpathogenic Phaeosphaeria sp., which were not detected in the agar plate-based assay. Traditionally, Fusarium fungi were identified by mycological assay. However, the resolution of DNA metabarcoding was sufficient to determine main Fusarium groups divided by ability to produce toxic secondary metabolites. The combined list of Ascomycetes consisted of 15 genera, including 14 fungi identified to species level. The list of Basidiomycota derived from DNA metabarcoding data alone included 8 genera. Conclusion. It was found that crop season predetermines the fungal community structure; mycobiota on the surface and inside of grain was significantly different.

Alternaria fungi dominate the grain microbiota in many regions of the world, therefore, the detection of species that are able to produce mycotoxins has received much attention. A total of 178 grain samples of wheat, barley and oat obtained from the Urals and West Siberia regions of Russia in 2017–2019 were included in the study. Grain contamination with Alternaria fungi belonging to sections Alternaria and Infectoriae was analysed using qPCR with specific primers. The occurrence of four mycotoxins produced by Alternaria, AOH, AME, TEN, and TeA, was defined by HPLC-MS/MS. Alternaria DNA was found in all analysed grain samples. The prevalence of DNA of Alternaria sect. Alternaria fungi (range 53 × 10−4–21,731 × 10−4 pg/ng) over the DNA of Alternaria sect. Infectoriae (range 11 × 10−4‒4237 × 10−4 pg/ng) in the grain samples was revealed. Sixty-two percent of grain samples were contaminated by at least two Alternaria mycotoxins. The combination of TEN and TeA was found most often. Eight percent of grain samples were contaminated by all four mycotoxins, and only 3% of samples were free from the analysed secondary toxic metabolites. The amounts varied in a range of 2–53 µg/kg for AOH, 3–56 µg/kg for AME, 3–131 µg/kg for TEN and 9–15,000 µg/kg for TeA. To our knowledge, a new global maximum level of natural contamination of wheat grain with TeA was detected. A positive correlation between the amount of DNA from Alternaria sect. Alternaria and TeA was observed. The significant effects of cereal species and geographic origin of samples on the amounts of DNA and mycotoxins of Alternaria spp. in grain were revealed. Barley was the most heavily contaminated with fungi belonging to both sections. The content of AOH in oat grain was, on average, higher than that found in wheat and barley. The content of TEN in the grain of barley was lower than that in wheat and similar to that in oat. The content of TeA did not depend on the cereal crop. The effect of weather conditions (summer temperature and rainfall) on the final fungal and mycotoxin contamination of grain was discussed. The frequent co-occurrence of different Alternaria fungi and their mycotoxins in grain indicates the need for further studies investigating this issue.

Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. In 2013, the

The biological characterization of Microdochium majus, M. nivale, and M. seminicola strains with wide geographical origins showed the diversity of their pathogenic properties and metabolite compounds, allowing them to exist in their habitats. Significant differences in the ability of Microdochium fungi to cause lesions on wheat and oat leaves were found. The intensity of symptoms depended on the species and substrate origin of the strains. On average M. seminicola strains were able to cause less leaf necrosis than M. majus and M. nivale. The volatile organic compound (VOC) profile of Microdochium fungi included 29 putative fungal metabolites. The spectrum of the identified VOCs in M. seminicola strains was much richer than that in M. majus and M. nivale strains. In addition, the strains of M. seminicola emitted at least six sesquiterpenes. Mycotoxin analysis by HPLC/MS/MS revealed that the analyzed Microdochium strains did not produce any toxic metabolites typically produced by filamentous fungi.

In total, 46 Microdochium strains from five different geographic regions of Russia were explored with respect to genetic diversity, morphology, and secondary metabolites. Based on the results of PCR, 59% and 28% of the strains were identified as M. nivale and M. majus, respectively. As a result of sequencing four genome regions, namely ITS, LSU, BTUB, and RPB2 (2778 bp), five genetically and phenotypically similar strains from Western Siberia were identified as M. seminicola, which, according to our findings, is the prevalent Microdochium species in this territory. This is the first record of M. seminicola in Russia. Attempts were made to distinguish between Microdochium species and to identify species-specific morphological characteristics in the anamorph and teleomorph stages and physiological properties. We examined the occurrence frequency of conidia with different numbers of septa in the strains of Microdochium. The predominance of three-septate macroconidia in M. majus was higher than that in M. nivale and typically exceeded 60% occurrence. Most M. majus and M. nivale strains formed walled protoperithecia on wheat stems. Only three strains of M. majus and one strain each of M. nivale and M. seminicola produced mature perithecia. The growth rate of M. seminicola strains was significantly lower on agar media at 5&ndash, 25 &deg, C than those of M. majus and M. nivale strains. Multimycotoxin analysis by HPLC-MS/MS revealed that the strains of three Microdochium species did not produce any toxic metabolites.

Four different fungicides that recommended to control seed-borne pathogens, were tested in this study. Three fungicides contain singly pyraclostrobin (200 g/L), thiram (400 g/L), fludioxonil (25 g/L), and one fungicide contains together imazalil, metalaxyl, and tebuconazole (50, 40, and 30 g/L, respectively). Comparative assessment of the fungicides at four concentrations of active substance (10, 100, 1 000, and 10 000 ppb) on the growth of ten strains of Fusarium spp. was studied in vitro tests. To visualize the effect of fungicides on fungal growth the strains were cultivated in 50 mL liquid Czapek medium containing fungicides in the range of concentrations. The fungicide based on pyraclostrobin was the most effective in growth inhibition of Fusarium fungi. Broadly, the using of this fungicide is confident way to control Fusarium species, which are serious threat to crop production. The sensitivity of F. acuminatum, F. graminearum, F. semitectum, F. culmorum, F. sporotrichioides, F. equiseti strains to fungicides was higher in compare with the strains belonging to F. oxysporum, F. solani, F. verticillioides, and F. proliferatum.

The microbiological quality of 23 grain samples of wheat and barley harvested in the North Caucasus in 2019 was analysed on the basis of the percentage of grains infected by fungi and the amounts of trichothecene-producingFusariumDNA andAlternariaDNA. The mycotoxins produced by these fungi were also determined.AlternariaandFusariumfungi were the predominant fungi in the mycobiota of grain, accounting for at 93% and 14% of the observed fungi, respectively. Alternariol produced byAlternariafungi was detected in 65% of samples, and its content (11-675 ppb) was positively correlated with the abundance of fungi of sectionAlternariain grain.F. langsethiaewas found in wheat grain from the Chechen Republic for the first time. The T-2 toxin produced by this fungus was found in 25% of samples, and its content in one barley grain reached 650 ppb, which exceeded the permitted level for this mycotoxin. The mycotoxins deoxynivalenol and zearalenone, which are mainly produced byF. graminearum, were also identified in 13% of the grain samples. The positive correlation between the amounts of both these mycotoxins and the DNA of Tri-Fusariumwas established.

The compositions of volatile organic compounds (VOCs) emitted by Fusarium fungi (F. langsethiae, F. sibiricum, F. poae, and F. sporotrichioides) grown on two nutritive substrates: potato sucrose agar (PSA) and autoclaved wheat kernels (WK) were investigated. The culturing of fungi and study of their VOC emissions were performed in chromatographic vials at room temperature (23 - 24 °C) and the VOCs were sampled by a solid-phase microextraction on a 85 μm carboxen/polydimethylsiloxane fiber. GC/MS was performed using a 60-m HP-5 capillary column. Components of the VOC mixture were identified by electron impact mass spectra and chromatographic retention indices (RIs). The most abundant components of the VOC mixture emitted by Fusarium fungi are EtOH, AcOH, (i) BuOH, 3-methylbutan-1-ol, 2-methylbutan-1-ol, ethyl 3-methylbutanoate, terpenes with M 136, sesquiterpenes with M 204 (a total of about 25), and trichodiene. It was found that the strains grown on PSA emit a wider spectrum and larger amount of VOCs compared with those grown on wheat kernels. F. langsethiae strain is the most active VOC producer on both substrates. The use of SPME and GC/MS also offers the potential for differentiation of fungal species and strains.

Enzymes capable of modifying the sulfated polymeric molecule of fucoidan are mainly produced by different groups of marine organisms: invertebrates, bacteria, and also some fungi. We have discovered and identified a new strain of filamentous fungus Fusarium proliferatum LE1 (deposition number in Russian Collection of Agricultural Microorganisms is RCAM02409), which is a potential producer of fucoidan-degrading enzymes. The strain LE1 (RCAM02409) was identified on the basis of morphological characteristics and analysis of ITS sequences of ribosomal DNA. During submerged cultivation of F. proliferatum LE1 in the nutrient medium containing natural fucoidan sources (the mixture of brown algae Laminaria digitata and Fucus vesiculosus), enzymic activities of α-L-fucosidase and arylsulfatase were inducible. These enzymes hydrolyzed model substrates, para-nitrophenyl α-L-fucopyranoside and para-nitrophenyl sulfate, respectively. However, the α-L-fucosidase is appeared to be a secreted enzyme while the arylsulfatase was an intracellular one. No detectable fucoidanase activity was found during F. proliferatum LE1 growth in submerged culture or in a static one. Comparative screening for fucoidanase/arylsulfatase/α-L-fucosidase activities among several related Fusarium strains showed a uniqueness of F. proliferatum LE1 to produce arylsulfatase and α-L-fucosidase enzymes. Apart them, the strain was shown to produce other glycoside hydrolyses.

Analysis of 49 strains of Fusarium langsethiae originating from northern Europe (Russia, Finland, Sweden, UK, Norway, and Latvia) revealed the presence of spontaneous auxotrophic mutants that reflect natural intraspecific diversity. Our investigations detected that 49.0% of F. langsethiae strains were auxotrophic mutants for biotin, and 8.2% of the strains required thiamine as a growth factor. They failed to grow on vitamin-free media. For both prototrophic and auxotrophic strains, no growth defect was observed in rich organic media. Without essential vitamins, a significant reduction in the growth of the auxotrophic strains results in a decrease of the formation of T-2 toxin and diacetoxyscirpenol. In addition, all analysed F. langsethiae strains were distinguished into two subgroups based on PCR product sizes. According to our results, 26 and 23 strains of F. langsethiae belong to subgroups I and II respectively. We determined that the deletion in the intergenic spacer (IGS) region of the rDNA of F. langsethiae belonging to subgroup II is linked with temperature sensitivity and causes a decrease in strain growth at 30 °C. Four thiamine auxotrophic strains were found in subgroup I, while 21 biotin auxotrophic strains were detected in subgroups II. To the best of our knowledge, the spontaneous mutations in F. langsethiae observed in the present work have not been previously reported.

In this letter, we advocate recognizing the genus Fusarium as the sole name for a group that includes virtually all Fusarium species of importance in plant pathology, mycotoxicology, medicine, and basic research. This phylogenetically guided circumscription will free scientists from any obligation to use other genus names, including teleomorphs, for species nested within this clade, and preserve the application of the name Fusarium in the way it has been used for almost a century. Due to recent changes in the International Code of Nomenclature for algae, fungi, and plants, this is an urgent matter that requires community attention. The alternative is to break the longstanding concept of Fusarium into nine or more genera, and remove important taxa such as those in the F. solani species complex from the genus, a move we believe is unnecessary. Here we present taxonomic and nomenclatural proposals that will preserve established research connections and facilitate communication within and between research communities, and at the same time support strong scientific principles and good taxonomic practice Fil: Geiser, David M.. State University of Pennsylvania; Estados Unidos Fil: Aoki, Takayuki. National Institute of Agrobiological Sciences; Japón Fil: Bacon, Charles W.. Toxicology and Mycotoxin Research; Grecia Fil: Baker, Scott E.. Pacific Northwest National Laboratory; Estados Unidos Fil: Bhattacharyya, Madan K.. University of Iowa; Estados Unidos Fil: Chulze, Sofia Noemi. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Scandiani, María Mercedes. Laboratorio Agrícola Río Paraná. San Pedro; Argentina Fil: Ploetz, Randy C.. University of Florida; Estados Unidos Fil: Proctor, Robert H.. NCAUR-ARS-USDA; Estados Unidos Fil: Rehner, Stephen A.. United States Department of Agriculture; Estados Unidos Fil: Robert, Vincent A. R. G.. Fungal Biodiversity Center; Países Bajos Fil: Rooney, Alejandro P.. NCAUR-ARS-USDA; Estados Unidos Fil: Salleh, Baharuddin bin. University of Malaysia; Malasia Fil: Scauflaire, Jonathan. Université Catholique de Louvain; Bélgica Fil: Short, Dylan P. G.. University of California; Estados Unidos Fil: Steenkamp, Emma. University of Pretoria; Sudáfrica Fil: Suga, Haruhisa. Gifu University; Japón Fil: Summerell, Brett A.. The Royal Botanic Garden Sydney; Australia Fil: Sutton, Deanna A.. University of Texas; Estados Unidos Fil: Thrane, Ulf. Technical University of Denmark; Dinamarca Fil: Trail, Francis. Michigan State University; Estados Unidos Fil: Van Diepeningen, Anne. Fungal Biodiversity Center; Países Bajos Fil: VanEtten, Hans D.. University of Arizona; Estados Unidos Fil: Viljoen, Altus. University of Stellenbosch; Sudáfrica Fil: Waalwijk, Cees. Wageningen University; Países Bajos Fil: Ward, Todd J.. NCAUR-ARS-USDA. Pretoria; Sudáfrica Fil: Wingfield, Michael J.. University of Pretoria; Sudáfrica Fil: Xu, Jin-Rong. Purdue University; Estados Unidos Fil: Yang, Xiao-Bing. University of Iowa; Estados Unidos Fil: Yli-Mattila, Tapani. University of Turku; Finlandia Fil: Zhang, Ning. Rutgers University; Estados Unidos

Production of type A trichothecenes has been reported in the closely related species Fusarium langsethiae and F. sporotrichioides. Here, we characterized a collection of Fusarium isolates from Siberia and the Russian Far East (hereafter Asian isolates) that produce high levels of the type A trichothecene T-2 toxin and are similar in morphology to the type A trichothecene-producing F. langsethiae, and to F. poae which often produces the type B trichothecene nivalenol. The Asian isolates possess unique macroscopic and microscopic characters and have a unique TG repeat in the nuclear ribosomal intergenic spacer (IGS rDNA) region. In Asian isolates, the TRI1–TRI16 locus, which determines type A versus type B trichothecene production in other species, is more similar in organization and sequence to the TRI1–TRI16 locus in F. sporotrichioides and F. langsethiae than to that in F. poae. Phylogenetic analysis of the TRI1 and TRI16 gene coding regions indicates that the genes in the Asian isolates are more closely related to those of F. sporotrichioides than F. langsethiae. Phylogenetic analysis of the beta-tubulin, translation elongation factor, RNA polymerase II and phosphate permease gene sequences resolved the Asian isolates into a well-supported sister lineage to F. sporotrichioides, with F. langsethiae forming a sister lineage to F. sporotrichioides and the Asian isolates. The Asian isolates are conspecific with Norwegian isolate IBT 9959 based on morphological and molecular analyses. In addition, the European F. langsethiae isolates from Finland and Russia were resolved into two distinct subgroups based on analyses of translation elongation factor and IGS rDNA sequences. Nucleotide polymorphisms within the IGS rDNA were used to design PCR primers that successfully differentiated the Asian isolates from F. sporotrichioides and F. langsethiae. Based on these data, we formally propose that the Asian isolates together with Norwegian isolate IBT 9959 comprise a novel phylogenetic species, F. sibiricum, while the two subgroups of F. langsethiae only represent intraspecific groups.

We investigated Fusarium graminearum complex (Fg complex) species diversity and toxin potential in European and Asian regions of the Russian Federation and adjoining regions northwest to Finland and south near Harbin, Heilongjiang Province, China, to expand our knowledge of the host range and geographic distribution of these economically devastating cereal head blight pathogens. Results of a recently described multilocus genotyping (MLGT) assay revealed that F. graminearum was the sole Fg complex pathogen in northern Europe and the predominant one in Asia (90.5%). Even though isolates of F. graminearum were segregating for 3-acetyldeoxynivalenol (3ADON) and 15-acetyldeoxynivalenol (15ADON) chemotype in nearly equal frequencies in the regions sampled on both continents, significant differences in the geographic distribution of isolates producing these acetyl ester derivatives of deoxynivalenol (DON) were observed in Europe. While 93.5% of the isolates in southern Russia (n = 43 of 46) possessed the 15ADON chemotype, isolates of F. graminearum recovered in Finland and northwestern Russia (n = 40) were exclusively 3ADON producers. Based on results of the MLGT assay, species identity of 10 genetically novel Fg complex isolates from the Russian Far East was investigated further via molecular phylogenetic analyses of multilocus DNA sequence data. Results of these analyses resolved these isolates as a phylogenetically distinct, reciprocally monophyletic sister lineage of F. asiaticum, which together with F. vorosii form a newly discovered Asian clade within the Fg complex. Because this novel lineage fulfills the highly conservative criterion of genealogical exclusivity under phylogenetic species recognition it is formally described herein as F. ussurianum. In addition to morphologically characterizing isolates of F. ussurianum, experiments were conducted to assess pathogenicity to wheat and trichothecene toxin potential in planta.

PCR assays that yield markers that are predictive of NIV versus DON production or 3ADON versus 15ADON production were performed for 60 Fusarium graminearum isolates, most of which were from Finland and Russia. None of the F. graminearum isolates originating from Finland and north-western Russia produced any PCR fragment with DON and NIV specific primers, which indicates that they have a 3ADON chemotype. All F. graminearum isolates from southern Russia and most of the isolates from Asia and Germany produced fragments typical of the 15ADON chemotype. All F. culmorum isolates belonged to 3ADON chemotype, while all F. cerealis isolates belonged to NIV chemotype. The highest DON levels were found in the 3ADON molecular chemotype isolates of Finland, north-western Russia, and central Russia. In the combined 3ADON molecular chemotype isolates, DON production was clearly higher than in the combined 15DON chemotype isolates.