A phylogenetic overview of Squamanita, with descriptions of nine new species and four new combinations

Nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode) sequence data from eight type specimens of previously described Squamanita species were obtained. Phylogenetic analysis of ITS and partial nuc 28S rDNA data revealed Squamanita as paraphyletic splitting into two monophyletic groups, which we recognize as the genera Squamanita and Dissoderma. We accept 14 Squamanita and nine Dissoderma species, provide the first sequences of 13 of these, and describe six new species of Squamanita and three new species of Dissoderma. We transfer three species of Squamanita into Dissoderma, one into Cystoderma, and treat S. basii and S. umbilicata as synonyms of D. paradoxum. Squamanita can be distinguished from Dissoderma by the generally larger fleshier basidiomata with a tricholomatoid or amanitoid stature and yellowish to tawny brown pileus and often similarly colored stipe. Most species have cheilo- and pleurocystidia. Species of Dissoderma are small, collybioid or mycenoid, lack cystidia, and the pileus and often upper stipe are purplish gray. Both genera parasitize basidiomata of other agarics.

Tricholoma olivaceonigrum, a new species of the section Tricholoma (Agaricales) from Japan

A novel species of Tricholoma section Tricholoma, namely, T. olivaceonigrum, is described and illustrated based on samples found in an oak woods dominated by Quercus myrsinifolia, an evergreen oak, in Tottori Prefecture, western Japan. It is characterized by a conic-umbonate, dark-greenish olivaceous pileus with blackish innate fibrils; a whitish silky-fibrillose stipe, often faintly tinted pale yellow and with a narrowed subpointed base; subglobose to broadly elliptic spores; and fruiting in early winter. Phylogenetic analysis targeting the internal transcribed spacer region of the ribosomal RNA gene revealed that T. olivaceonigrum forms a well-supported clade sister to T. portentosum. Other morphologically and phylogenetically closely related species of the section Tricholoma are discussed.

Productivity and bioactivity of enokipodins A-D of Flammulina rossica and Flammulina velutipes

Enokipodins are antimicrobial sesquiterpenes produced by Flammulina velutipes in a mycelial culture medium. To date, enokipodin production has not been reported in other members of the genus Flammulina. Hence, in this study, the production of enokipodins A, B, C, and D by F. velutipes and F. rossica was investigated. Some strains of F. rossica were confirmed to produce at least one of the four enokipodins in the culture medium. However, some strains of F. velutipes did not produce any of the enokipodins. In an antibacterial assay using liquid medium, enokipodin B showed the strongest growth inhibitory activity against Bacillus subtilis among the four types of enokipodins. Enokipodin B inhibited the spore germination of some plant pathogenic fungi. Enokipodins B and D exerted moderate anti-proliferative activity against some cancer cell lines, and enokipodins A and C inhibited the proliferation of the malarial parasite, Plasmodium falciparum.

A global view of Gyroporus: molecular phylogenetics, diversity patterns, and new species

Gyroporus (Gyroporaceae, Boletales) is a highly diverse genus of poroid ectomycorrhizal mushrooms with a nearly worldwide distribution. Previous attempts to unravel the diversity within this genus proved difficult due to the presence of semicryptic species and ambiguous results from analysis of ribosomal RNA markers. In this study, we employ a combined morphotaxonomic and phylogenetic approach to delimit species and elucidate geographic and evolutionary patterns in Gyroporus. For phylogenetic analyses, the protein-coding genes atp6 (mitochondrial adenosine triphosphate [ATP] synthase subunit 6) and rpb2 (nuclear second largest subunit of RNA polymerase II) were selected based on their utility in studies of Boletales. We infer several distinct clades, most notably one corresponding to G. castaneus as a speciose Northern Hemisphere group, another unifying G. cyanescens and like entities, and a third group unifying G. longicystidiatus and a New World sister species. Also notable is the recovery of a sister relationship between the cyanescens and longicystidiatus clades. We formally describe five new species of Gyroporus, outline a number of provisional species, and briefly discuss distributional patterns. This study provides an important scaffold for future work on this well-known but poorly understood genus of fungi.

Identification and symbiotic ability of Psathyrellaceae fungi isolated from a photosynthetic orchid, Cremastra appendiculata (Orchidaceae)

PREMISE OF THE STUDY

Photosynthetic orchids found in highly shaded forests are often mixotrophic, receiving part of their carbon energy via ectomycorrhizal fungi that had originally received carbohydrate from trees. A photosynthetic orchid, Cremastra appendiculata, is also found under highly shaded forest, but our preliminary data suggested that its associated fungi were not ectomycorrhizal. We tested whether their relation is an unusual example of a mixotrophic orchid associating with saprotrophic fungi by direct detection of fungal DNAs in conjunction with isolation of the fungus in pure culture and experimental inoculation of orchid seeds with the fungus. •

METHODS

For isolated mycobionts of C. appendiculata plants, two regions of nuclear ribosomal DNA, the internal transcribed spacer (ITS) and the large subunit (LSU), were sequenced, and fruiting bodies of the one isolate, SI1-1 were induced. In addition, two fungal isolates, SI1-1 and KI1-1, were grown in symbiotic cultures with C. appendiculata to verify their status as mycobionts. •

KEY RESULTS

In phylogenetic analyses, all isolates clustered with fungi belonging to Coprinellus in Psathyrellaceae of Agaricales. Phylogenetic analyses of these DNA sequences showed that five fungal isolates from C. appendiculata, including SI1-1 and two mycobionts isolated from the mycoheterotrophic orchid Epipogium roseum, have very similar ITS sequences. Isolate SI1-1 was identified as Coprinellus domesticus based on the morphological characteristics of the fruiting body. Isolates SI1-1 and KI1-1 induced seed germination of C. appendiculata as mycobionts. •

CONCLUSIONS

This report is the first of a mycorrhizal symbiosis between a fungus in Psathyrellaceae and a photosynthetic orchid, revealing a new pathway to full mycoheterotrophy and contributing to our understanding of the evolution of mycoheterotrophy.

Trichoderma mienum sp. nov., isolated from mushroom farms in Japan

During an investigation of Hypocrea/Trichoderma species inhabiting mushroom bedlogs, we found five strains of an undescribed species from a culture collection. These were analyzed using a combined approach, including morphology of holomorph, cultural studies, and phylogenetic analyses of the rRNA gene cluster of the internal transcribed spacer region, translation elongation factor 1-α, and RNA polymerase subunit II gene sequences. Distinctive morphological characters include stromata with green ascospores produced on potato dextrose agar medium, and Gliocladium-like to irregularly Verticillium-like conidiophores. In phylogenetic analyses, this species belongs to the Semiorbis clade, but its morphological characteristics do not match the other members of this clade. Based on morphological observations and phylogenetic analyses, we describe this as a new species, Trichoderma mienum, representing its Hypocrea teleomorph and Trichoderma anamorph.

Identification of the biological species of Armillaria associated with Wynnea and Entoloma abortivum using PCR-rFLP analysis of the intergenic region (IGR) of ribosomal DNA

Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis of the first intergenic region (IGR1) of nuclear ribosomal DNA was used to clarify the relationship between IGR1 variations and six Japanese biological species of Armillaria: A. gallica, A. nabsnona, A. ostoyae, A. cepistipes, A. mellea and Nagasawa's E (Nag. E: taxonomically unknown species). The procedure was then used to identify Armillaria species associated with Wynnea species (W. americana and W. gigantea) and Entoloma abortivum. By combining the RFLP patterns obtained using three endonucleases, HaeIII, HinfI and MspI, the IGR1s from 18 isolates of six Armillaria species were assigned to nine different RFLP phenotypes and the six species were distinguished from each other. Each of the RFLP phenotypes from the Armillaria isolates associated with Wynnea species or E. abortivum matched a corresponding phenotypes observed among the six Armillaria species. Based on this, all four isolates from W. gigantea were identified as A. mellea, two from W. americana as A. cepistipes, and all three from E. abortivum as Nag. E. These results provide new information on the biological species of Armillaria associated with Wynnea and E. abortivum.

Biological Species of Armillaria in Japan

Pairing tests with isolates of Armillaria in culture were used to identify species of Armillaria and their distribution throughout Japan. The existence of 10 intersterile groups of Armillaria was determined by pairing haploid single spore isolates obtained from 20 basidiocarps from a wide geographic distribution in Japan. Two to four haploid tester isolates from each intersterile group were then paired to biological and morphological species with haploid tester isolates from Europe and North America identified in previous studies. Japanese haploid tester isolates were then paired with 190 haploid or diploid isolates and compatibility reactions were used to identify these to species. Of the 10 intersterile groups identified in Japan, 7 were authenticated as A. gallica, A. nabsnona, A. ostoyae, A. cepistipes, A. mellea, A. sinapina, or A. tabescens. Three of the groups were not compatible with any of the tester species. The distribution and host relationships of the Japanese biological species are also discussed.