Cystotheca lanestris on the new host Quercus canbyi, Microidium bauhiniicola on the new host Bauhinia macranthera and an undescribed species of Phyllactinia on Mimosa aculeaticarpa have recently been collected in Mexico. Analyses of morphological traits and molecular sequence data led to identifications of the causal agents of the powdery mildew diseases involved. Microidium bauhiniicola, hitherto only known from Argentina and Brazil, is new to Mexico. The phylogenetic analysis revealed an isolated position distant from Microidium indicating an undescribed genus, which is introduced as Bulbomicroidium gen. nov. Sequences derived from a Mexican specimen of C. lanestris on Quercus canbyi agree completely with other North American sequences, but differ from sequences retrieved from Asian collections, suggesting that C. lanestris in Asia is not conspecific with C. lanestris s. str. in North America. A new species of Phyllactinia on Mimosa malacophylla is morphologically similar to P. dalbergiae but readily distinguishable by differences in the asexual morph. Based on morphological peculiarities and results of molecular sequence analyses, this species is described as Phyllactinia mimosae sp. nov.

We investigated changes in the expression of Tmpal1 and Tmpal2, that encode phenylalanine ammonia-lyases (PALs), during the growth of Tricholoma matsutake NBRC 30605 mycelia, and the effect of exogenously added _L-phenylalanine (_L-Phe), a substrate of PALs, on _pal expression and methyl cinnamate production in the mycelia. Expression patterns of Tmpal1 and Tmpal2 differed during mycelial growth. Transcript levels of Tmpal2, PAL activity, and methyl cinnamate content increased markedly in cultures supplemented with 4–6 mM _L-Phe. These results indicate that _L-Phe supplementation increases PAL activity that is mainly responsible for Tmpal2 expression; consequently, methyl cinnamate is abundantly produced from _L-Phe.

Albatrellus roseus sp. nov. is described from Swat, Pakistan, based on morphological and molecular data. Morphological descriptions and illustration for the new species and comparison with closely allied species are provided. Phylogenetic analyses based on nuclear ribosomal DNA (nuc-rDNA) internal transcribed spacer (ITS1-5.8S-ITS2) and 28S loci are studied. This study represent the first record of the genus Albatrellus from Pakistan.

Mycorrhizal fungi were isolated and cultured from rhizomes of mycoheterotrophic Cremastra aphylla (Orchidaceae) plants collected in 3 sites across Japan. In total, 5 Cr. aphylla individuals were collected, and 10 fungal isolates were obtained. Sequence analysis of the internal transcribed spacer regions (ITS) of nuclear ribosomal DNA from the fungal samples revealed that all isolates belonged to the genus Coprinellus in the family Psathyrellaceae. All isolates from each site were of the same phylotype. In total, 3 ITS phylotypes were detected. One of the isolates produced fruiting bodies and was identified as Co. domesticus on the basis of macro- and microscopic characteristics of the basidiomata and ITS sequence data. In this study, the sharing of saprobic Psathyrellaceae fungus by the mycoheterotrophic and leafy Cremastra species was newly confirmed.

Knowledge of fungal root-associates is essential for effective conservation of tropical epiphytic orchids. We investigated the diversity of root-associated fungi of Cyrtochilum myanthum, Scaphyglottis punctulata and Stelis superbiens from a tropical mountain rainforest in southern Ecuador, using a culture dependent approach. We identified 115 fungal isolates, corresponding to 49 fungal OTUs, based on sequences of the nrDNA ITS and partial 28S region. Members of Ascomycota were unambiguously dominant (37 OTUs), including Trichoderma sp. as the most frequent taxon. Members of Basidiomycota (Agaricales and Polyporales) and Mucoromycota (Umbelopsidales and Mortierellales) were also identified. Four potential mycorrhizal OTUs of Tulasnellaceae and Ceratobasidiaceae were isolated from C. myanthum and S. superbiens. Fungal community composition was examined using Sørensen and Jaccard indices of similarity. Alfa diversity was significantly different between C. myanthum and S. superbiens. No difference in beta diversity of the fungal communities between the 3 orchid species and the collecting sites was detected. The study revealed a high diversity of fungi associated with orchid roots. Our results contribute to a better understanding of specific relationships between epiphytic orchids and their root-associated fungi.

Ossicaulis is a small genus in the family Lyophyllaceae. Two known species, O. lachnopus, and O. lignatilis, are distributed in north temperate regions. The third taxon, O. yunnanensis sp. nov., is described from the alpine belt of subtropics of southwestern China, and this genus is also reported for the first time from China. Morphologically, the new species is characterized by its whitish basidiomata and very small basidiospores. Molecular analyses from the nuclear rDNA internal transcribed spacer region (ITS) show that the subtropical alpine species is distinct from hitherto known Ossicaulis species and has a close relationship to O. lachnopus.

Biotic interactions play an important role in the assembly and stability of communities. All orchids depend on mycobionts for early establishment, but whether individual orchid species depend on a specific or broad spectrum of mycobionts is still a matter of debate. Tulasnellaceae (Basidiomycota) is the richest and most widespread mycobiont worldwide. We assessed Tulasnellaceae richness in epiphytic and terrestrial orchids in different habitats, and evaluated the degree of generalism in orchid-Tulasnellaceae interactions and the robustness of this mutualistic system to the extinction of mycobiont partners. We sampled 114 orchid individuals including all common and rare species in 56 plots of 1 m² in 3 habitats: pristine forest, regenerating forest and a landslide site in a tropical montane rainforest in Southern Ecuador. We found 52 orchid and 29 Tulasnellaceae species. The composition of Tulasnellaceae OTUs was moderately to highly similar across habitats and between orchid growth forms. A significantly nested network architecture indicated the existence of a core of generalist Tulasnellaceae OTUs interacting with both rare and common orchids. Terrestrial and epiphytic orchids showed significant differences in robustness to the extinction of their Tulasnellaceae mycobionts. Thus, generalist mycobionts may be relevant for the preservation of hyperdiverse orchid communities in the tropics.

Coltriciella minuscula sp. nov. is described and illustrated from a specimen collected on Pinus merkusii from Bogor, Indonesia. This species is characterized by the size of its basidiocarp up to 4 mm in diam, with long hair on the stipe and with ornamented spores. Both morphological distinctiveness and phylogenetic separation based upon analyses of nrDNA ITS sequences support the establishment of this new species. Morphological dissimilarities between C. minuscula and closely related species are discussed.

Two strains of a psychrophilic basidiomycetous yeast species belonging to the genus Mrakia were isolated from a melt-pool mat community, on an ice island located in Disraeli Fjord, Ellesmere Island in the Canadian Arctic. Analysis of the large subunit rDNA D1/D2 domain and internal transcribed spacer region sequences indicated that these strains represent a novel species, and the name Mrakia arctica sp. nov. is proposed. This new species could grow at sub-zero temperatures and in vitamin-free media. Moreover, lipase and cellulase enzymes of M. arctica were strongly active even at −3 °C. These results suggest an important role for M. arctica in the biogeochemical cycle of glacial ecosystems.

During the last decade, our concept of chytrid systematics has dramatically changed based on molecular phylogeny and zoospore ultrastructure. In contrast with well-studied saprotrophic chytrids, only a few obligate parasitic chytrids have been investigated with modern methods. Here, we investigate the novel chytrid culture KS93 that is parasitic on the diatom Aulacoseira granulata. Thallus morphology of KS93 was characterized by a spherical, stalked zoosporangium with a single, apical inoperculate discharge pore and zoospore discharge as a mass in a vesicle. A cross-inoculation experiment revealed that the infection of KS93 was specific to A. granulata. Zoospores of KS93 possessed the characters of the Group I type zoospore of the Chytriomycetaceae in the Chytridiales, but does not appear to have a paracrystalline inclusion. Additionally, KS93 also possessed a globule-type KAS (kinetosome-associated structure), first reported here for members of Chytriomycetaceae. In our molecular phylogeny, KS93 was placed in the basal position of the Chytriomycetaceae and was distinguished from any known species in the family. Morphological features of KS93 were distinct from those of any other taxa in the Chytriomycetaceae and from any described chytrids. Based on these results, we describe this chytrid as Pendulichytrium sphaericum gen. et sp. nov. in the family Chytriomycetaceae.

A new cold-adapted yeast species, Gelidatrema psychrophila sp. nov., was isolated from a melt-pool microbial mat community, on an ice island located in Disraeli Fjord, Ellesmere Island, in the Canadian High Arctic. Molecular analysis of the D1/D2 domain sequence of the large subunit rDNA showed that this species is novel and could grow at sub-zero temperatures and in vitamin-free media. These characteristics were likely acquired by the yeast to survive in extreme, perennially cold oligotrophic environments.

An asexual morph of a powdery mildew was found on Buddleja asiatica (Scrophulariaceae) in Nepal. The morphological traits of this powdery mildew strongly resemble those of Phyllactinia species (including Ovulariopsis) belonging to a phylogenetically basal group closely related to Leveillula species, but phylogenetic examinations and analyses clearly showed that this fungus pertains to Leveillula. Within the latter genus, it seems to be allied to L. duriaei, but clearly differs from this species in having conidiophores arising from superficial hyphae and narrower conidia with different length/width ratios. Therefore, the powdery mildew on B. asiatica is described as Leveillula buddlejae sp. nov.

During dismantling and relocation of the Takamatsuzuka Tumulus stone chamber, many Cladophialophora and chaetothyrialean black fungi, such as Exophiala and Phialophora, were isolated from samples taken from the joints between the stone walls. However, inside the stone chamber of the Kitora Tumulus, after intermittent UV irradiation in 2009, these black fungi were also isolated from samples taken from the stone walls. Molecular phylogenetic analyses based on only nrLSU and the concatenated (nrLSU D1/D2 + ITS) sequences revealed that the 35 Takamatsuzuka and Kitora Tumuli isolates of Cladophialophora and the chaetothyrialean black fungi were divergent. Two new species of Cladophialophora are described herein: C. tumulicola from the viscous gels and various substrates on the stone walls of the Takamatsuzuka and Kitora Tumuli and C. tumbae from black substances on the plastic cover over the “thief hole,” soil and plaster pieces between the stone walls, and the exterior of the Takamatsuzuka Tumulus chamber. Also, molecular phylogenetic placements for the remaining eight Takamatsuzuka and Kitora Tumuli isolates of chaetothyrialean black fungi have been determined or suggested.

Since the mid-nineties Phyllactinia fraxini has become frequent in Germany. This species has hitherto been characterized by having straight conidiophore foot cells. However, we found that recent collections from Germany have conidiophores with sinuated and twisted foot cells. So far sinuated foot cells were only known from the related P. fraxinicola, another species with Eastern Asian origin. We thus hypothesized that recent collections from Germany belong to P. fraxinicola which might have been introduced to Europe. Using morphological and molecular rDNA data we found that no introduction took place and that there is only P. fraxini in Germany.

The Japanese delicacy Tricholoma matsutake has been conducted in vitro ectomycorrhizal syntheses for more than 20 y. The development of its ectomycorrhizal structures varies among experimental systems. Here, we examined the effects of soil-fungus interactions on the early stage of in vitro T. matsutake ectomycorrhization. Axenic Pinus densiflora seedlings were transplanted into autoclaved natural inorganic soil, inoculated with the cultured mycelium of T. matsutake, and incubated for 90 d in vitro. Both soil type and fungal strain significantly affected host plant growth; host plant growth and mycorrhization levels significantly differed among soil type/fungal strain combinations. Therefore, the selection of T. matsutake strains for optimal mycorrhization must take into account such fungal and soil properties.