Mycoscience最新文献

Typhula ishikariensis and the related fungi were separated into three biological species by morphological and physiological characteristics, as well as DNA sequences and mating reactions. We propose that the T. ishikariensis complex should be divided into three species (T. ishikariensis, T. canadensis and T. hyperborea) and two varieties (T. ishikariensis var. ishikariensis and var. idahoensis). Typhula hyperborea was reappraised to be recognized also as a separate species of the T. ishikariensis complex.

Phylogenetic and morphological analyses have been conducted on powdery mildew specimens on different Berberis and Mahonia spp. from Asia, Europe and North America. The present study showed that collections of Erysiphe berberidis exhibit a high degree of morphological plasticity of the sexual morph, in contrast to their morphologically, rather uniform, asexual morph. In phylogenetic tree, all sequences cluster in a large strongly supported clade, without any indication and support for further differentiation into cryptic species. There are three morphological types within E. berberidis s. lat. that contain consistent differences. Until future multi-locus analyses will be available, we prefer to treat these 'morphological types' as varieties. These include Erysiphe berberidis var. berberidis, E. berberidis var. asiatica, and E. berberidis var. dimorpha comb. nov. (≡ Microsphaera berberidis var. dimorpha, M. berberidicola, and M. multappendicis). To fix the application of species name E. berberidis, an appropriate epitype was designated, with an ITS sequences.

Microbial symbionts are essential for plant niche expansion into novel habitats. Dormant propagules of ectomycorrhizal (EM) fungi are thought to play an important role in seedling establishment in invasion fronts; however, propagule bank communities above the treeline are poorly understood in the Eurasian Arctic, where treelines are expected to advance under rapid climate change. To investigate the availability of EM fungal propagules, we collected 100 soil samples from Arctic tundra sites and applied bioassay experiments using Larix cajanderi as bait seedlings. We detected 11 EM fungal operational taxonomic units (OTUs) by obtaining entire ITS regions. Suillus clintonianus was the most frequently observed OTU, followed by Cenococcum geophilum and Sebacinales OTU1. Three Suillus and one Rhizopogon species were detected in the bioassay seedlings, indicating the availability of Larix-specific suilloid spores at least 30 km from the contemporary treeline. Spores of S. clintonianus and S. spectabilis remained infective after preservation for 14 mo and heat treatment at 60 °C, implying the durability of the spores. Long-distance dispersal capability and spore resistance to adverse conditions may represent ecological strategies employed by suilloid fungi to quickly associate with emerging seedlings of compatible hosts in treeless habitats.

We describe a new species of Gerhardtia from Japan based on basidiomata morphology, live culture characteristics, and molecular phylogenetic analyses. Gerhardtia venosolamellata is found on broad-leaf litter, and is characterized by tricholomatoid to marasmioid basidiomata, an off-white to pale salmon-pink pileus surface with faint marginal striae, subdistant lamellae with lateral veins, a tomentose to strigose stipe base with hyphal strands generating arthroconidia measuring 4-7 × 2-3 µm, cyanophilic, elongate-ellipsoid to cylindrical, slightly verrucose or undulate basidiospores measuring 4.5-6 × 2.5-3 µm, and cyanophilic basidia measuring 25-35 × 5-6 µm and containing siderophilous granules. Phylogenetic analyses based on the internal transcribed spacer and large subunit regions of the fungal nrDNA indicates that G. venosolamellata is related to G. sinensis and G. highlandensis, but differs from the former with respect to basidiomata color, basidiospore shape, and habitat. An isotype specimen of G. highlandensis exhibited relatively close lamellae without veins, and slightly larger basidiospores (4.5-6.5 × 2.5-3 µm). Cultured mycelia of G. venosolamellata produced arthroconidia measuring 4.5-8.5 × 2.5-3 µm with both schizolytic and rhexolytic secession on MA and PDA media, and chlamydospores occasionally covered with crystals on MA and MYG media.

We describe two new species of Fulvifomes based on morphological observations and phylogenetic investigations. Both species were identified as Phellinus rimosus by former mycologists, but both are morphologically distinct from authenticated specimen of P. rimosus. Fulvifomes boninensis is characterized by perennial basidiomata, a sulcate pileus surface becoming rimose, lack of a distinct crust on the pileus surface, subdimitic hyphal system in the context, and ellipsoid basidiospores. This species is endemic to the Bonin Islands, Japan, and is specific to the host Morus boninensis, a red-listed tree species. Fulvifomes imazekii is characterized by perennial basidiomata, sulcate and velutinous pileus surface, lack of a crust on the pileus surface, dimitic hyphal system in the context, and broadly ellipsoid basidiospores. This species is specific to Berchemiella berchemiaefolia, and is known only from Mt. Yokogura-yama, in Kochi Prefecture, Japan. Fulvifomes boninensis and F. imazekii are considered threatened, because of their high host specificity each with a threatened tree species as well as the limited distribution of the former and the extremely small number of "mature individuals" of the latter. The following new combinations were also proposed: Fulvifomes aulaxinus, F. pappianus, and F. tepperi.

Myconymphaea yatsukahoi is a fungus that has only been isolated once from a forest in the Sugadaira Research Station, Nagano, Japan. Over 20 y have passed since its first discovery but since then it has not been rediscovered. Here, we re-isolated M. yatsukahoi from the type locality and another location, Tambara Moor, Gunma, Japan. Sporophores of this species were detected by direct field observation in Sugadaira and by induction from soil from Tambara. We attempted to narrow down isolation sources of this species by investigating the excrements of Lithobiomorpha and Scolopendromorpha centipedes, which are frequently found in the two locations where the species is distributed. In both locations, we found M. yatsukahoi in the excrements of Lithobiomorpha but not Scolopendromorpha. Myconymphaea yatsukahoi appears to be a coprophilous fungus and the excrements of the predators living in soil may be promising isolation sources for understanding the hidden diversity of kickxellalean fungi.

Due to the high crude fiber content, straw of various crops is difficult to become a high quality forage resource. The degradation of cellulose in nature mainly depends on the cellulase secreted by microbes, which degrade cellulose into small molecular substances through chemical action, and the microbes that secrete cellulase mainly include some bacteria, fungi and actinomycetes, etc. The large and diverse microbial population contained in the mammalian gastrointestinal tract plays an important role in nutrient digestion. At present, many cellulose-degrading strains have been screened and obtained from animal digestive system and feces, such as Bacillus subtilis from the feces of Panda, Bacillus amyloliquefaciens from the cecum of goose. In this study, the fungal diversity was analysed in the fresh faeces of Tibetan sheep, Tibetan gazelle and Tibetan antelope in Qiangtang, Tibet. Results showed that the structure and species of gut fungi are different in three animals, which may be related to the different physiological functions among different animals, e.g., Tibetan antelope and Tibetan gazelle have stronger tolerance to rough feeding than Tibetan sheep. This study will lay a foundation for cellulose-degrading fungal development and provides technical support for improving rough feeding tolerance of Tibetan sheep.

We describe two new species of resupinate Sistotrema sensu lato (Cantharellales) collected in Japan: S. flavorhizomorphae and S. chloroporum. Both species have urniform basidia with more than four sterigmata and monomitic hyphal system, oil-rich hyphae in subiculum, which is typical for this genus. Sistotrema chloroporum is characterized by poroid hymenophore partly yellowish-green, basidia 4-6-spored, medium-sized basidiospores (4.5-6.5 × 3.5-6 µm), and broadleaf forest habitat. Sistotrema flavorhizomorphae is characterized by hydnoid-irpicoid hymenophore, bright yellowish rhizomorphs, basidia 6-8-spored, small basidiospores (3-3.5 × 2.5-3 µm), and pine forest habitat. Phylogenetic trees inferred from the fungal nrDNA ITS and LSU and the rpb2 sequences supported that both species were distinct and grouped with other ectomycorrhizal Sistotrema and Hydnum species, but their generic boundary was unclear. Mycorrhizae underneath basidiomes of both species were identified and described via molecular techniques. Mycorrhizae of S. chloroporum have similar characteristics to those of other Sistotrema s.l. and Hydnum species, i.e., S. confluens and H. repandum, whereas S. flavorhizomorphae has a distinct morpho-anatomy, for example, a distinct pseudoparenchymatous mantle. Comprehensive characterizations of basidiomes and mycorrhizae improve the taxonomic analysis of mycorrhizal species of Sistotrema s.l.

Puccinia caricis-smilacis, a new species of caricicolous rust fungus was described based on morphological characteristics and nuclear rDNA sequences from Japan. The heteroecious life cycle of P. caricis-smilacis was elucidated via field observations, inoculation experiments and molecular analyses. This rust fungus produces uredinial and telial stages on Carex fibrillosa, and spermogonial and aecial stages on Smilax china.

A white-colored truffle Tuber japonicum, indigenous to Japan, is an ascomycetous ectomycorrhizal fungus. To clarify the physiological characteristics of this fungus, we investigated the influence of culture medium, temperature, and sources of nitrogen (N) and carbon (C) on the growth of five strains. Tuber japonicum strains grew better on malt extract and modified Melin-Norkrans medium, and showed peak growth at 20 °C or 25 °C. This fungus utilized inorganic (NH₄ ⁺ and NO₃ ^-) and organic N sources (casamino acids, glutamine, peptone, urea, and yeast extract). Additionally, this fungus utilized various C sources, such as monosaccharide (arabinose, fructose, galactose, glucose, and mannose), disaccharide (maltose, sucrose, and trehalose), polysaccharide (dextrin and soluble starch), and sugar alcohol (mannitol). However, nutrient sources that promote growth and their effects on growth promotion widely varied among strains. This can result from the strain difference in enzyme activities involved in the assimilation and metabolism of these sources.