Mycological Progress最新文献

Fabaceae, one of the largest flowering plant families, comprises several subfamilies and genera. Fabaceous plant species host a large number of powdery mildew species belonging to the genus Erysiphe. The affiliation of these species to Erysiphe is readily possible, but they represent a morphologically and taxonomically complicated complex of closely related, morphologically similar species with overlapping traits. Precise morphological examinations along with phylogenetic analyses, including type collections and other representative samples, are needed to solve the complexity of Erysiphe spp. on legumes. In this study, we sequenced a number of collections of powdery mildews on Pisum, Lathyrus, Vicia and Ononis spp., with a special focus on specimens from Iran, to clarify species delimitations within the Erysiphe pisi complex and other Erysiphe species complexes on legumes. Sequences retrieved from powdery mildew on Pisum and Ononis fall into separate, well supported clades. Hence, the original status of E. cruchetiana as a species of its own on Ononis spp. is reinstated instead of E. pisi var. cruchetiana. Ten species, viz., E. astragali, E. bremeri, E. caulicola, E. cruchetiana, E. iranica, E. medicaginis, E. pisi, E. rayssiae, E. sesbaniae and E. trifoliorum were confirmed for Iran, redescribed and illustrated on the basis of Iranian collections. Erysiphe astragali, E. bremeri, E. coluteae and E. crispula form a genetically little differentiated clade in ITS/LSU analyses, which is referred to as E. astragali clade (complex), comparable to the E. trifoliorum clade (complex). Based on our results, E. coluteae and E. crispula are reduced to synonymy with E. astragali and E. sophorae is considered a synonym of E. bremeri. Sequences of the North American E. intermedia on Lupinus species form a small clade nested within the big E. astragali clade. DNA of the holotype of E. sesbaniae was sequenced for the first time in this study. To use the sequences obtained from some new collections as reference sequences for phylogenetic-taxonomic purposes, we propose, for the interim, reference sequences for E. bremeri, E. caulicola, E. cruchetiana, E. pisi and E. viciae-unijugae.

Xylodon lanatus and closely related species were studied with molecular and morphological means. This species complex contains six species, two of which we describe as new. Species in the complex have minutely odontioid hymenophore projections that consist of encrusted, firm-walled hyphae and ellipsoid spores. We assign an epitype for X. lanatus, for which ITS and 28S rDNA sequences were obtained, and amend the concept of X. pseudolanatus. The two new species, both well supported in our phylogenetic analyses, are X. afromontanus, found in Eastern Africa, and X. mantiqueirensis, found in southeastern Brazil. We show the phylogenetic affinity of X. echinatus with X. lanatus for the first time, and according to new data the range of the previous species extends to Sunda Archipelago. We provide scanning electron microscopy illustrations of the crystalline deposits on projecting hyphae for the above-mentioned species. The sixth member of the complex is X. kunmingensis. Outside the X. lanatus complex, we report additional sequenced specimens of X. hyphodontinus. A new species, X. neotropicus from South America, related to X. hyphodontinus, is described. We also describe X. gloeocystidiifer from Ecuador as new species. It is characterised by globose/broadly ellipsoid spores, gloeocystidia and capitate cystidia with a resinous cap. The heterotypic names Hyphodontia yunnanensis and Xylodon yunnanensis are considered. We suggest the previous one is a synonym of the latter.

Owing to ineffective biological nitrogen (N) fixation, and imbalanced doses of N and potassium (K) fertilization, soybean productivity is declining under intensive cropping practices. This study aimed to find out the effectiveness of Trichoderma viride priming on soybean root growth promotion, and enhancement of soil-N and K uptakes under graded fertilization. Soybean seeds were treated with freshly prepared T. viride BHU-2953 talc. Root lignification, indole acetic acid (IAA) production, and activity of 1-aminocyclopropane-1-carboxylate deaminase (ACCD) were determined to observe root growth-promoting activities. A pot experiment was conducted to evaluate root volume, and soil exploration by roots, i.e., the potential volume of influence (PVI), uptakes of N and K, and different physiological attributes at different growth periods of soybean. Results revealed that biopriming enhanced the root lignification, IAA, and ACCD, assisting more soil volume exploration (PVI) for better N and K acquisitions. Biopriming increased the plant biomasses which ultimately, led to more seed yield than untreated soybeans, receiving even higher N-K doses. The PVI correlated well with root volume (r² = 0.95; P < 0.01), explaining good soil-nutrient foraging by bioprimed soybeans. Hence, we conclude that T. viride priming can enhance the N and K uptakes in soybeans under graded soil fertilization.

Sequencing ribosomal DNA loci, such as ITS and LSU, are among the first steps to characterize and identify newly isolated fungal strains. Substantial doubt has recently been raised concerning the unequivocal suitability of using this sequence information for inferring inter- and intraspecific relationships, as especially the ITS locus was repeatedly shown to harbor high intragenomic plasticity. The evolutionary mechanisms leading to this phenomenon are poorly understood, but this is about to change, owing to the availability of third generation sequencing techniques. The current study attempts a comprehensive analysis of rDNA cistrons in the genomes of over 40 selected species of Hypoxylaceae (Xylariales), using a combination of 2nd generation (Illumina) and 3rd generation sequencing technologies (Oxford Nanopore), along with extensive usage of bioinformatic tools to obtain high-quality genomes. Our findings revealed high intragenomic polymorphisms in distinct Hypoxylaceae species, indicating the presence of deep rDNA paralogs. Phylogenetic inference of the ITS rDNA showed low support for the primary clades within Hypoxylaceae, while inference using the protein encoding gene RPB2 showed better support. We also found that proteinogenic genes are not prone to intraspecific and intragenomic polymorphisms as much as the rDNA loci. Our study highlights the limitations of solely relying on the rDNA cistron as a barcode for fungi. We propose TUB2 as a new primary barcoding marker for Hypoxylaceae and other Xylariales. Moreover, we demonstrate the feasibility to retrieve some DNA loci that had hitherto not been used for classical phylogenetic studies (such as TEF1) in Xylariales directly from genomes without the necessity to work with primers.

Preparative high-performance liquid chromatography (HPLC) purification of the ethyl acetate extract derived from dried basidiomes of the European mushroom Hericium coralloides led to the identification of two previously undescribed isoindolinone derivatives named corallocins D and E (1-2). The structures of the compounds were elucidated based on HR-ESI-MS (high-resolution electron spray ionization mass spectrometry), interpretation of 1D and 2D NMR spectra, electronic circular dichroism (ECD) experiments, and comparisons with published and theoretical data. The metabolites were tested for their cytotoxic and antimicrobial effects in vitro where weak to moderate biological effects were observed against HeLa cells (KB 3.1), Mucor hiemalis and Bacillus subtilis.

Nacobbus aberrans is a plant parasitic nematode that causes significant economic losses in the American Continent and is considered a quarantine pest in many countries. Some arbuscular mycorrhizal fungi have shown the ability to reduce the population of this pathogen; however, most studies do not consider other relevant aspects that have to do with the crop or the fungus. The purpose of this work was to select an isolated mycorrhizal fungus based on a comprehensive analysis of the Nematode–Plant–Mycorrhizal Fungus system. The test was conducted on Solanum lycopersicum L. grown in pots. The evaluated isolates were Funneliformis mosseae, Rhizoglomus intraradices A2, and Rhizoglomus intraradices B1. All the isolates reduced the nematode population significantly; however, differences in the content of photosynthetic pigments, soluble proteins, and osmoregulatory metabolites were identified. All of these impacted on the photosynthetic rates of the different treatments. There were also differences in the growth of the fungi within the roots, and in the viability of the fungal structures. The comprehensive analysis of the plant–nematode–fungus group allows us to conclude that the isolate with the greatest capacity to compensate for the negative effect of parasitism, and with the greatest possibility of lasting as a biocontrol agent is Funneliformis mosseae.

During the assessment of coprophilous mucoralean diversity in northeastern areas of Brazil, a Lichtheimia-like specimen (URM 8358) was isolated from rabbit dung. It was characterized based on morphological, physiological, and molecular analyses of the internal transcribed spacer (ITS), large subunit ribosomal (LSU) and actin DNA sequences. These analyses revealed a novel Lichtheimia species, which is described herein. The novel species forms abundantly branched sporangiophores, with most branches arising near the main sporangia, various-shaped columellae, and irregularly shaped sporangiospores. Furthermore, this manuscript provides notes of all Lichtheimia species, and an identification key for the genus is provided. These findings contribute to the existing knowledge on the taxonomy and distribution of Lichtheimia. Because of the clinical relevance of other Lichtheimia species, we encourage future research to determine whether URM 8358 can be pathogenic to humans.

Cladochytriales comprises a taxonomic order and lineage of chytrid fungi that are primarily saprobes of organic matter in aquatic and terrestrial ecosystems. The order contains species from 12 genera, though molecular confirmations of almost all type species are lacking, and many genera are considered polyphyletic. We conducted phylogenetic analyses of ribosomal RNA genes and developmental morphology of Cladochytriales isolates from the Collection of Zoosporic Eufungi at the University of Michigan and noted some strains that were distinct from described genera. In our phylogenetic analysis, Endochytriaceae represented by only one strain of Endochytrium ramosum was sister to Septochytriaceae while the incertae sedis lineage formed by the new species Thomasia carolinae was sister to Nowakowskiellaceae. Additionally, the phylogenetic relatedness of the other two new species, Dogmamyces elongatus and Allochytrium aureum, was also highly supported. A thorough revision of the order is needed because some genera, such as Catenochytridium and Nephrochytrium, remain polyphyletic or paraphyletic. In addition to indicating these problems, our updated phylogeny supports the description of two new genera and three new species and thereby begins to bring the knowledge of the Cladochytriales up to date.