Mycoscience最新文献

Species of Hypochnicium (Polyporales, Basidiomycota) collected from Japan were studied on their taxonomy by morphological and phylogenetic approaches. Phylogenetic analyses based on a nrDNA LSU and ITS dataset including the Japanese specimens and other publicly available ones show that Hypochnicium is polyphyletic. Since the clade containing the type species H. bombycinum was well-supported, we defined this clade as Hypochnicium s. str., and emended Hypochnicium to include restricted taxa with only smooth basidiospores. The new genus Neohypochnicium is proposed to accommodate the remaining taxa excluded from the genus Hypochnicium s. str., which includes both species with smooth basidiospores and ornamented ones. Three new species, Gyrophanopsis japonica, N. asiaticum and N. perlongicystidiosum are described and illustrated based on morphological and phylogenetic analyses using an ITS region dataset. In addition, the following 15 new combinations are proposed: N. albostramineum, N. aotearoae, N. capitulateum, N. cremicolor, N. cystidiatum, N. geogenium, N. guineense, N. huinayense, N. michelii, N. microsporum, N. patagonicum, N. pini, N. punctulatum, N. subrigescens and N. wakefieldiae. An identification key to Japanese species of Bulbillomyces, Gyrophanopsis, Hypochnicium and Neohypochnicium is provided.

Chinese yam (Dioscorea polystachya) has been cultivated as a food crop in Japan. The blue mold disease of Chinese yam during the storage and treatment of forced sprouting is one of the hindrances in attaining productivity that can lead to food security in tropical countries and steady farming that will eventually lead to farmers' profitability. In this study, three species of the genus Penicillium related to the blue mold of yam were isolated from two locations in Hokkaido, Japan. From the morphology and phylogeny, these were Penicillium albocoremium, P. polonicum, and P. sclerotigenum. Pathogenicity was confirmed in all Penicillium-like isolates, and sensitivity against benomyl was evaluated based on MIC. The first two species were newly recorded as the causal fungi of the blue mold of yam in Japan, and the pathogenicity of P. albocoremium is first confirmed in yam seed tuber. Moreover, some isolates showed possible resistance to benomyl.

Gentiana zollingeri (Gentianaceae) is an initial mycoheterotrophic plant that depends on a specific group of arbuscular mycorrhizal (AM) fungi for carbon source during underground growth after seed germination. In this study, a mycorrhizal fungus dominant in mycoheterotrophic seedlings of G. zollingeri was successfully isolated from a soil core collected from a point close to a flowering G. zollingeri. The AM fungal isolate was identified as conspecific or closely related to Dominikia aurea (Glomeraceae) by spore morphology and molecular phylogeny. Basic Local Alignment Search Tool (BLAST) searches against the MaarjAM database showed that the nuclear small subunit ribosomal DNA sequences of the isolate matched the AM fungal sequences obtained from a wide range of plants in various ecosystems, including several mycoheterotrophs. Thus, it is suggested that the AM fungal isolate is one of the cheating susceptible AM fungi. Furthermore, the sequences corresponded to those of a group of AM fungi dominantly detected in Japanese temperate forests. Accordingly, there is a possibility that mycoheterotrophic plants, including seedlings of G. zollingeri, may target AM fungi with a wide host range and ubiquitous distribution.

The genus Schizoplasmodiopsis is one of the most morphologically diverse groups among the class Variosea. Recent phylogenetic studies suggest that Schizoplasmodiopsis is polyphyletic, but there are few taxonomic studies of this genus. We established S. micropunctata strain YIP-40, observed in detail its of morphology and lifecycle, and conducted a phylogenetic analysis. The phylogenetic analysis revealed that S. micropunctata was sister to Tychosporium acutostipes. Scanning electron microscopy showed S. micropunctata had a non-deciduous hilum structure that is unique to Tychosporium. The morphology of amoebae, mitotic behavior, and prespore cells of S. micropunctata also supported the close relationship to Tychosporium. We propose to transfer S. micropunctata to Tychosporium and emend the generic concept of Tychosporium to include this species.

Rhodocybe subasyae is described from northeast China as a new species with both morphological and molecular characteristics, which is morphologically characterized by its tricholomatoid basidiomata, orange white to beige red pileus, adnexed to sinuate lamellae and long clavate branched cheilocystidia within section Rufobrunnea. The phylogenetic tree based on internal transcribed spacers of rDNA (nrITS) sequences using Bayesian methods showed that new taxon was distinguished from other species of Rhodocybe.

There is increasing incidence of food spoilage and health hazards caused by heat-resistant fungi belonging to the genera Byssochlamys, Thermoascus, and Neosartorya, among others. Their ascospores cannot be sterilized by heating the food. The microbiological risk assessment studies of these fungi during the production of food and beverages indicated that these fungal species or genera in food are associated with different health risks. Therefore, it is necessary to distinguish Byssochlamys, Thermoascus, and Neosartorya from other fungi in the food industry. These genera can be identified by sequence analysis of housekeeping genes such as β-tubulin, but the process is costly and time-consuming. Therefore, rapid and simple PCR-based methods have been developed using specific primer sets for genus- or species-level identification. PCR amplification products are observed to be specific for each of these genera or species and do not cross-react with other fungi associated with food spoilage and environmental contamination. These identification methods are simple, rapid, and highly specific, making them feasible for use in the quality management of food production plants.

Wood-rotting fungi are important components of woody plant ecosystems and play an active role in the decomposition and turnover of nutrients from wood, and are among the major groups of Basidiomycota. In this study, a new species of wood-rotting fungus, Sistotrema yunnanense, was proposed based on morphological characteristics and molecular evidence. It is characterized by resupinate basidiomata, a monomitic hyphal system having generative hyphae with clamp connections, suburniform to urniform basidia, and short-cylindrical to oblong ellipsoid basidiospores (4.5-6.5 × 3-4 µm). Phylogenetic analyses performed using the large subunit nuc rDNA indicated that S. yunnanense was nested within the genus Sistotrema s.l. of the family Hydnaceae, within the order Cantharellales.

Lasiodiplodia species cause dieback, shoot blight, fruit rot, and stem-end rot of woody plants. Recently, studies on taxonomic revision of Lasiodiplodia species have been conducted globally and have led to more clarification of the species diversity of this genus. However, only three species of the genus have been reported in Japan. To evaluate the species diversity of Lasiodiplodia in Japan, we re-examined the taxonomical positions of 30 isolates based on their morphological and cultural characteristics and phylogenetic relationships. Phylogenetic analyses were performed using a matrix comprising ITS, tef1, tub2, and rpb2 sequences, and the results indicate that the examined Japanese isolates belong to six species: Lasiodiplodia brasiliensis, L. hormozganensis, L. pseudotheobromae, L. thailandica, L. theobromae, and Lasiodiplodia sp. Moreover, three of these species were newly added to the Japanese mycoflora.