Mycobiology最新文献

Endophytic fungi associated with seaweeds have increasingly attracted attention due to their ecological roles and potential as biological resources. In this study, fungal endophytes were isolated from the brown alga Sargassum thunbergii, collected in intertidal habitats of Seongsan-eup, Jeju-do and Buan-gun, Jeollabuk-do, Korea. Identification was carried out using an integrative approach that combined morphological characterization with multilocus phylogenetic analyses of ITS, LSU, SSU, TUB2, RPB2, and CaM sequences. Six fungal taxa were identified as new records for Korea: Botryotrichum murorum, Hypomontagnella spongiphila, Subramaniula cristata, Parachaetomium perlucidum, Palmiascoma acericola, and Aspergillus clavatophorus. Detailed morphological descriptions and phylogenetic analysis supporting the identification of these species are provided. These findings expand our knowledge of fungal diversity associated with S. thunbergii and highlights the ecological importance and potential applications of seaweed-associated endophytes in Korea.

Endophytic fungi play essential roles in plant resilience and sustainable agriculture. Among these, dark septate endophytic (DSE) fungi are recognized for their ability to colonize plant root tissues and contribute to stress tolerance. In this study, a potential DSE isolate, designated as FX2, was obtained from agricultural soil in Tsukuba, Ibaraki, Japan. Morphological and phylogenetic analysis of the isolate showed the isolate as a novel species within the genus Cladophialophora (proposed as C. novalis). Physiological characterization revealed that C. novalis FX2 is sensitive to salinity, with colony growth decreasing significantly with the addition of ≥50 mM NaCl, prefers a near-neutral pH range of 5.5-7.0, and exhibits moderate drought tolerance with growth sustained up to 15% PEG. Despite C. novalis FX2 was isolated directly from soil, this isolate demonstrated endophytic ability without pathogenic symptoms in Chinese cabbage, maize and tomato, and increasing maize biomass significantly by 51.6% compared with uninoculated plants. These findings highlight C. novalis FX2 as a promising novel DSE candidate to enhance plant growth.

Two novel fungal species (KNUF-24-1Ha^T and KNUF-24-3La^T), belonging to the genus Exophiala, were isolated from galls produced by gall-midge (Lasioptera sp.; Diptera: Cecidomyiidae) on a Chinese magnolia vine (Schisandra chinensis) collected in Mungyeong-si, Gyeongbuk province, South Korea. Molecular analyses based on combined sequences of the internal transcribed spacer (ITS) regions and partial sequences of the large subunit (LSU), rRNA, beta-tubulin, and actin genes revealed that the strains clustered within the Exophiala genus. However, strains KNUF-24-1Ha^T and KNUF-24-3La^T each occupied a distinct phylogenetic position. Comparative analysis of the morphological characteristics of KNUF-24-1Ha^T and KNUF-24-3La^T and those of closely related species in the phylogenetic tree revealed distinct differences in the shape and size of conidia, conidiogenous cells, and yeast cells. Based on molecular and morphological evidence, strains KNUF-24-1Ha^T and KNUF-24-3La^T represent a novel species within the genus Exophiala, now designated as Exophiala schisandrae sp. nov. and E. exsudans sp. nov., respectively.

Marine fungi play a crucial role in maintaining the ocean ecosystem functions by participating in organic matter degradation, carbon and nitrogen biogeochemical cycles, and interactions with other marine organisms. Nevertheless, many marine habitats remain poorly explored for fungal diversity, as fungi have historically been overlooked in marine research. In this study, we investigated marine fungi in two underexplored coastal habitats (PET plastic waste and seafoam) collected from the intertidal zone of Udo Island, South Korea. A total of 88 fungal strains were isolated and identified as 45 taxa (22 taxa from PET waste and 24 from seafoam) based on multigene phylogenetic analysis and morphological characteristics. The distinct fungal communities recovered from PET plastic waste and seafoam highlight the ecological value of anthropogenic and ephemeral marine habitats. Among these, we report two novel species - Leptospora conidiifera sp. nov. and Neodevriesia oceanoplastica sp. nov. - along with five previously unrecorded marine fungi species in Korea. These findings suggest that the two habitats can serve as reservoirs of unique fungal biodiversity and marine fungi may play unrecognized roles in marine nutrient cycling and microbial interactions.

Sclerotium (=Agroathelia) rolfsii and S. delphinii are soilborne fungal pathogens responsible for southern blight and collar rot in numerous crops worldwide. Accurate detection and identification of these related pathogens are critical for disease management and the selection of resistant plant cultivars. In this study, we identified a polymorphic simple sequence repeat (SSR) locus through reference genome sequence analysis and developed a quantitative PCR (qPCR)-based high-resolution melting (HRM) assay to distinguish S. delphinii, S. rolfsii, and two intraspecific groups (G1 and G2) of S. rolfsii. Using a single primer pair in a closed-tube system without probes, HRM analysis differentiated the target groups by melting temperature profiles and detected as little as 1 pg of genomic DNA. The assay was validated on pure cultures, artificially inoculated soil, and rhizosphere soil from diseased tomato plants. This qPCR-HRM method provides a rapid, cost-effective, and robust diagnostic tool for the detection and discrimination of S. rolfsii G1, S. rolfsii G2, and S. delphinii, complementing conventional PCR and probe-based qPCR diagnostics.

The genus Xylaria Hill ex Schrank is an ecologically significant group of wood-decaying fungi that contribute to nutrient cycling and ecosystem stability in forests worldwide. Despite a recent global increase in the descriptions of new species, Korean Xylaria species have rarely been reexamined using modern taxonomic frameworks. In this study, dried specimens preserved at the Korea National Arboretum were re-identified through integrative morphological and molecular analyses using four genetic markers (ITS, ACT, TUB2, and RPB2). Consequently, one previously unrecorded species (Xylaria frustulosa) and three novel species (Heteroxylaria aciculiformis, Xylaria gwangneungensis, and Xylaria pratimongolica) were discovered. Morphological observations revealed that H. aciculiformis is characterized by its slender, needlelike, unbranched stromata with fine longitudinal striations and semi-exposed perithecia; X. gwangneungensis has distinctive capitate stromata with a short stipe and a solitary perithecium; and X. pratimongolica exhibits an erect, oriental brush-like stroma partially developed underground. Phylogenetic analyses supported the unique status of these taxa, as they formed distinct and well-supported clades separate from known species within Xylariaceae. These findings further elucidate the diversity of the Xylariaceae family and demonstrate the value of combining morphological and molecular data to resolve cryptic species within this genus.

The main objective of the present study is to compile and comprehensively reevaluate all known records of Cercospora dispori in order to establish a standardized framework for the accurate characterization and identification of this species. Nine isolates of C. dispori obtained from Disporum smilacinum and D. viridescens from various regions of Korea were analyzed. The morphological features of the fungus and isolated colonies were described and illustrated. Nucleotide sequences of the internal transcribed spacer (ITS) region, including the protein-coding genes, such as actin (actA), calmodulin (cmdA), translation elongation factor 1-alpha (tef1), and histone H3 (his3), were determined, and a phylogenetic tree was generated from a multi-gene dataset of ITS+tef1+act+cmdA+his3. This study provides a more robust taxonomic placement of C. dispori and clarifies its phylogenetic relationships within the genus Cercospora.

In a survey of freshwater and near-freshwater soils in Chungbuk, Gyeonggi, Gangwon, Gyeongbuk, and Gyeongnam provinces in Korea, seven fungal strains were isolated and identified as members of the genus Penicillium based on the internal transcribed spacer (ITS) regions sequence analyses. Identification was performed through observing morphological characteristics and conducting phylogenetic analyses based on concatenated partial ITS, β-tubulin, calmodulin, and RNA polymerase II subunit gene sequences. The phylogenetic analyses revealed that strain NNIBRFG6577 was distinct from known Penicillium species, and based on morphological comparisons with the closest related species, P. scruposum CGMCC 3.25167^T and P. subasperum CGMCC 3.25173^T, it was proposed as a novel species. Strains NNIBRFG4823, NNIBRFG4610, and NNIBRFG4600 were closely related to P. ellipsoideum CGMCC 3.25156^T, P. skrjabinii CBS 439.75^T, and P. yezoense CBS 350.59^T, respectively, while strains NNIBRFG1486, NNIBRFG48324, and NNIBRFG49919 clustered with P. pancosmium CBS 276.75^T, and all strains showed morphological characteristics similar to those of their respective reference strains. These findings enrich Korea's fungus inventory, providing a basis for valuable future resource development.

Freshwater ascomycetes are fungi that play an important role in the decomposition of submerged plant debris in freshwater habitats. At present, approximately 3000 species of ascomycetes have been described from freshwater habitats. However, the number of fungi in freshwater habitats in South Korea is small, and many species are still completely unknown. During investigations of freshwater ascomycetes in South Korea, three Dothideomycetes strains and seven Sordariomycetes strains were collected. Based on morphological and multigene phylogenetic analyses, one new species of Neopestalotiopsis was delimited: Neopestalotiopsis koreensis. In addition, Chaetocapnodium philippinense, Curvularia plantarum, Engyodontium rectidentatum, Fusarium arcuatisporum, Microdochium yunnanense, Septoriella verrucispora, Stephanonectria chromolaenae, and Trichoderma amoenum, are reported for the first time from South Korea. Herein, detailed descriptions and illustrations of the morphological characteristics of these species are provided.

Acremonium is a cosmopolitan and diverse genus of filamentous fungi, commonly isolated from soil and plant material, with several species recognized as opportunistic pathogens in both plants and humans. In this study, a novel species, Acremonium quercivorum sp. nov., is described from declining oak (Quercus spp.) trees in Algeria. This species is characterized by thin-walled hyphae, conidia oblong-ellipsoidal, and rounded at the apex, and subulate phialides with a thin neck at the apex. The multi-locus phylogenetic analyses combining ITS, LSU, RPB2, and TEF1 sequence data provide robust evidence supporting its distinction from A. egyptiacum and other closely related taxa. Comprehensive morphological descriptions, micrographs, and phylogenetic analyses of the new taxon associated with oak dieback are presented.