著者

Shuji Ushijima Eiji Nagasawa Naoki Endo Akiyoshi Yamada

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.62, no.4, pp.233-238, 2021-07-20 (Released:2021-07-20)

参考文献数

14

被引用文献数

2

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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.

著者

Ryotaro Shino Kozue Sotome Naoki Endo Nitaro Maekawa Akira Nakagiri

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.64, no.6, pp.136-149, 2023-11-20 (Released:2023-11-20)

参考文献数

72

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Physisporinus, a genus in Polyporales, Basidiomycota, is a versatile fungus that lives as a wood decomposer, a potential pathogen of standing trees, and an orchid mycobiont. We previously reported that some Physisporinus species inhabiting wet wood in aquatic environments such as streams and waterfalls form synnema-like structures (SSs) bearing acanthophyses at their apices, and that they produce acanthophyses on vegetative hyphae when cultured on agar media. In this study, we investigated the acanthophysis-forming ability in Physisporinus and allied genera, and experimentally demonstrated the function of SSs. Phylogenetic analyses and observations of Meripilus, Physisporinus and Rigidoporus cultures showed that all of the strains forming acanthophyses belonged to Physisporinus, whereas strains of Meripilus and Rigidoporus did not produce acanthophyses. These findings suggest that SS/acanthophysis formation is a useful taxonomic character for members of Physisporinus. When Physisporinus strains were cultured under oxygen (O2) concentrations of 5, 10, 20 and 40%, most of those cultured under 20% O2 formed the most acanthophyses. According to these experimental data, the SSs/acanthophyses in Physisporinus were considered to have a respiratory function. Physisporinus probably acquired the SS/acanthophysis-forming ability to adapt to moist and/or aquatic habitats and to decay wet wood in which the O2 concentration is often low.

著者

Kenya Tsuji Yuki Kitade Takuya Sumita Chihiro Tanaka

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.62, no.5, pp.289-296, 2021-09-20 (Released:2021-09-20)

参考文献数

29

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In this study, we identified Sec5 in Bipolaris maydis, a homologue of Sec5 in Saccharomyces cerevisiae and a possible exocyst component of the fungus. To examine how Sec5 affects the life cycle of B. maydis, we generated null mutant strains of the gene (Δsec5). The Δsec5 strains showed a strong reduction in hyphal growth and a slight reduction in pathogenicity. In sexual reproduction, they possessed the ability to develop pseudothecia. However, all ascospores were aborted in any of the asci obtained from crosses between Δsec5 and the wild-type. Our cytological study revealed that the abortion was caused by impairments of the post-meiotic stages in ascospore development, where ascospore delimitation and young spore elongation occur.

著者

Philippe Clowez Takumi Izumi Paul-Bill Lamiable Koichi Shibakusa Camelia Minculeasa Pablo Alvarado

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.63, no.6, pp.274-283, 2022-10-21 (Released:2022-11-20)

参考文献数

67

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A previously unknown morel species apparently endemic to Japan is here described. Morchella nipponensis is proposed for this species. This new taxon displays archaic features recalling section Rufobrunnea (pileus lanceolate, few primary alveoli), and a yellow pileus similar to subsection Sceptriformis of section Morchella. The phylogenetic analysis of ITS rDNA, as well as RPB1, RPB2 and TEF1 genes from up to four collections suggests that this morel species represents a basal branch of section Morchella (yellow morels), for which the new subsection Japonicae is proposed.

著者

Jun-Hong Dong Ya-Xing Wu Chang-Lin Zhao

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.63, no.2, pp.65-72, 2022-03-20 (Released:2022-03-31)

参考文献数

54

被引用文献数

3

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Two new wood-inhabiting fungal species, Steccherinum hirsutum and S. yunnanense spp. nov., are proposed based on a combination of morphological features and molecular evidence. Sequences of internal transcribed spacer and large subunit region of nuculear ribosomal RNA gene of the studied samples were generated, and phylogenetic analyses were performed using maximum likelihood, maximum parsimony and bayesian inference methods. Steccherinum hirsutum is characterized by an annual growth habit, stipitate basidiocarps with scarlet to red, odontioid hymenial surface, a dimitic hyphal system with clamped generative hyphae negative in Melzer's reaction, and acyanophilous basidiospores measuring 2.5-3.5 × 1.5-2.5 µm. Steccherinum yunnanense is distinguished by resupinate basidiomata with odontioid hymenial surface, a dimitic hyphal system with clamped generative hyphae, strongly encrusted cystidia and ellipsoid, hyaline, thin-walled, smooth basidiospores (3.5-4.5 × 2-3.5 µm). The phylogenetic analyses comfirmed that two new species nest in Steccherinum, in the residual polyporoid clade.

著者

Kazunari Takahashi Yu Fukasawa

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

pp.MYC563, (Released:2022-02-14)

被引用文献数

1

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The bark of live trees provides an important microhabitat for corticolous myxomycetes. However, the association between the presence of myxomycetes and health of host trees has not been studied in detail. In this study, we aimed to investigate the relationship between tree vitality and myxomycetes on the bark of Cryptomeria japonica trees in a montane forest in western Japan. The vitality of trees was categorized into four grades based on the visual assessment of tree shape and leaf density in the upper branches. Myxomycetes on the bark surface were examined using the moist chamber culture method. A decline in tree vitality increased bark pH and decreased electrical conductivity of the bark exudates. Seventeen myxomycete species were recorded in 74 C. japonica trees. The structure of myxomycete communities varied between healthy and unhealthy trees, and species diversity increased as the vitality declined. The relative abundance of Cribraria confusa decreased as the vitality declined, while that of Paradiacheopsis solitaria increased. The results showed that acidophilic myxomycetes grew on healthy C. japonica bark, but changes in bark pH associated with vitality decline led to the weakening of acidity and shifted the community structure; thus, corticolous myxomycete diversity was enhanced as tree vitality decline.

著者

Nitaro Maekawa

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.62, no.6, pp.345-355, 2021-11-20 (Released:2021-11-20)

参考文献数

111

被引用文献数

3

---

Corticioid fungi form effused basidiomata with various hymenophore configurations, mostly on woody substrates, and they are presently classified into 15 orders in Agaricomycotina in the phylum Basidiomycota. In this review, the corticioid fungi of Japan are treated on the basis of the current classification system, and all currently known species are listed and classified by order. Japanese corticioid fungi number 442 species in 160 genera belonging to 14 orders. Analysis of the distribution of Japanese corticioid species reveals that 375 species (85% of the total) have wide distributions, and that the Japanese corticioid fungal flora is composed of species with diverse patterns of distribution. In the subtropical regions, 146 corticioid species belonging to 77 genera are listed, including 100 species from the Nansei Islands and 76 from the Ogasawara Islands. Although these two island groups are located at similar latitudes, they share only 30 corticioid species―21% of the total reported from the subtropical regions. Along with this summary of the current status, this study presents future directions for the taxonomic research of the Japanese corticioid fungi.

著者

Boontiya Chuankid Santhiti Vadthanarat Benjarong Thongbai Marc Stadler Saisamorn Lumyong Kevin David Hyde Olivier Raspé

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.62, no.5, pp.297-306, 2021-09-20 (Released:2021-09-20)

参考文献数

32

被引用文献数

2

---

Morphological characters and multi-gene phylogenetic analyses were used to identify Retiboletus specimens collected in northern Thailand. Retiboletus brevibasidiatus is described as new to science, whereas R. fuscus and R. nigrogriseus are reported for the first time from Thailand. Retiboletus brevibasidiatus produces medium-sized basidiomes, with a dark blonde to clay pileus and densely reticulate stipe mostly on the upper part with pale yellow to chrome yellow basal mycelium. It is difficult to separate R. brevibasidiatus from other closely related species on the basis of macroscopic characters. However, the new species can be distinguished by microscopic characters, mostly the shorter basidia. The macro- and micro-morphology of the R. fuscus and R. nigrogriseus collections from Thailand fit well with the previous descriptions of materials from China and Japan. Detailed descriptions, molecular phylogeny, and illustrations of the three species are provided.

著者

Kaoru Yamaguchi

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.64, no.5, pp.128-135, 2023-09-30 (Released:2023-09-30)

参考文献数

73

---

Aero-aquatic fungi compose an ecological group of saprophytes inhabiting the submerged decaying substrates in stagnant freshwater environment. They produce three-dimensional shaped, multi-cellular conidia, which float on water surface by holding air between conidial cells. Because the conidia show diverse morphology, genus and species level classification have been based on their features. They are mostly known as asexual morphs of Ascomycota or Basidiomycota. Recent phylogenetic study revealed the aero-aquatic fungi appeared mainly in the lineages of Leotiomycetes, Dothideomycetes, and Sordariomycetes. Furthermore, the phylogenetic tree showed the aero-aquatic fungi have polyphyletic origins and similar three-dimensional conidial morphology generated as a convergent evolution among different lineages of fungi by the selection pressure for inhabiting freshwater environment. Recent studies suggested the ancestors of the aero-aquatic fungi were terrestrial fungi.

著者

Miao Liu Uwe Braun Susumu Takamatsu Sarah Hambleton Parivash Shoukouhi Kassandra R. Bisson Keith Hubbard

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

pp.MYC525, (Released:2021-03-13)

被引用文献数

20

---

A taxonomic revision of the hitherto monotypic genus Blumeria was conducted incorporating multi-gene sequence analyses, host preference data and morphological criteria. The sequenced loci included rDNA ITS, partial chitin synthase gene (CHS1), as well as fragments of two unnamed orthologous genes (Bgt-1929, Bgt-4572). The combined evidence led to a reassessment and a new neotypification of B. graminis s. str. (emend.), and the description of seven additional species, viz. B. americana sp. nov. (mainly on hosts of the Triticeae), B. avenae sp. nov. (on Avena spp.), B. bromi-cathartici sp. nov. (on Bromus catharticus), B. bulbigera comb. nov. (on Bromus spp.), B. dactylidis sp. nov. (on Dactylis glomerata as the main host, but also on various other hosts), B. graminicola sp. nov. (on Poa spp. as principal hosts, but also on various other hosts), and B. hordei sp. nov. (on Hordeum spp.). Synonyms were assessed, some were lectotypified, and questionable names previously associated with powdery mildew on monocots were discussed although their identities remained unresolved. Keys to the described species were developed.

著者

Ryo Sugawara Nana Shirasuka Tatsuki Yamamoto Kosuke Nagamune Kaito Oguchi Nitaro Maekawa Kozue Sotome Akira Nakagiri Shuji Ushijima Naoki Endo

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.63, no.3, pp.102-117, 2022-05-31 (Released:2022-05-31)

参考文献数

66

被引用文献数

3

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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.

著者

Hiroki Sato Sayaka Ban Tsuyoshi Hosoya

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

pp.MYC594, (Released:2022-12-26)

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Dr. Kobayasi and Mr. Shimizu described 31 species of Cordyceps infecting Lepidoptera. Holotype specimens of 14 species and two authentic specimens of one of the 31 species were rediscovered from a herbarium of the National Museum of Nature and Science (TNS). Registration numbers (TNS-F-number) were given to these 16 specimens, and one was lectotypified as follows. Holotypes: Metarhizium indigoticum TNS-F-230337; Yosiokobayasia kusanagiensis TNS-F-197994 (Clavicipitaceae); Beauveria hepialidicola (Kobayasi & Shimizu) Hirok. Sato, S. Ban & Hosoya, comb. nov. TNS-F-197986; Cordyceps ampullacea TNS-F-197981, Cordyceps militaris f. alba TNS-F-230340, Cordyceps ochraceostromata TNS-F-195471, and Cordyceps rosea TNS-F-197972 (Cordyceps sensu stricto, Cordycipitaceae); Ophiocordyceps aurantia TNS-F-195485, Ophiocordyceps cochlidiicola TNS-F-195470, and Ophiocordyceps hiugensis TNS-F-197978 (Ophiocordycipitaceae); and Cordyceps changpaishanensis TNS-F-195501, Cordyceps ootakiensis TNS-F-197976, Cordyceps shimizui TNS-F-197995, and Cordyceps sulfurea TNS-F-197974 (Cordyceps sensu lato). Lectotype: Cordyceps bulolensis TNS-F-230327 (Cordyceps sensu lato). A new combination Beauveria hepialidicola comb. nov., is proposed for Cordyceps hepialidicola based on morphological observations.

著者

Yuuki Kobayashi Miyuki Katsuren Masaru Hojo Shohei Wada Yoshie Terashima Masayoshi Kawaguchi Gaku Tokuda Kazuhiko Kinjo Shuji Shigenobu

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.63, no.1, pp.33-38, 2022-01-20 (Released:2022-01-20)

参考文献数

29

被引用文献数

3

---

Fungi in the genus Termitomyces are external symbionts of fungus-growing termites. The three rhizogenic Termitomyces species T. eurrhizus, T. clypeatus, and T. intermedius, and one species similar to T. microcarpus that lacks pseudorrhiza, have been reported from Ryukyu Archipelago, Japan. In contrast, only two genetic groups (types A and B) of Termitomyces vegetative mycelia have been detected in nests of the fungus-growing termite Odontotermes formosanus. In this study, we investigated the relationships between the mycelial genetic groups and the basidiomata of Termitomyces samples from the Ryukyu Archipelago. We found that all the basidioma specimens and the type B mycelia formed one clade that we identified as T. intermedius. Another clade consisted of the type A mycelia, which showed similarity to T. microcarpus, was identified as T. fragilis. Our results indicate that the Japanese T. eurrhizus and T. clypeatus specimens should re-named as T. intermedius.

著者

Ayuka Iwakiri Norihisa Matsushita Kenji Fukuda

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.62, no.6, pp.406-409, 2021-11-20 (Released:2021-11-20)

参考文献数

27

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Racodium therryanum is a snow mold causing snow blight and seed rot in conifers. The sexual stage of R. therryanum has not been found, however, it has been speculated that Herpotrichia juniperi, which causes brown felt blight, is the sexual stage of R. therryanum. In this study, we conducted phylogenetic analysis using 28S large subunit (LSU) rDNA, 18S small subunit (SSU) rDNA, translation elongation factor 1-alpha (tef1), and RNA polymerase II second largest subunit (rpb2). Four isolates were identified as R. therryanum based on their morphological characteristics; together with two strains of H. juniperi, they composed a clade supported by high bootstrap and Bayesian posterior probability values. Therefore, we conclude that the snow mold previously described as R. therryanum is phylogenetically H. juniperi.

著者

Yuta Sawada Toshitsugu Sato Ryosuke Fukushi Yoshihito Kohari Yuuki Takahashi Sayaka Tomii Lifeng Yang Takashi Yamagishi Hirofumi Arai

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.64, no.6, pp.156-165, 2023-11-20 (Released:2023-11-20)

参考文献数

41

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Edible basidiomycetes are highly active in the oxidative decomposition and polymerisation of polyphenols, and soybeans contain large amounts of isoflavones, which are polyphenol glycosides. Isoflavone aglycones exhibit weak estrogenic activities. In this study, we investigated the isoflavone content, polyphenol production, antioxidant activity and ergothioneine (EGT) content of soybeans fermented by Pleurotus cornucopiae and Pleurotus ostreatus. Isoflavone glycosides, which were abundant in unfermented soybeans, decreased, and aglycones increased on day 10 of culture in both edible basidiomycete-fermented soybeans. The total maximum polyphenol content in soybeans fermented by both mushrooms were approximately 4 times higher on day 30 to 40 of culture, than that of unfermented soybeans. P. cornucopiae-fermented soybeans showed maximum antioxidant activity on day 20 of culture, and this was approximately 6.1 times higher than that of unfermented soybeans. EGT was not detected in unfermented soybeans, whereas both fermented soybeans showed a maximum EGT content on day 20 of culture, which was especially high in P. cornucopiae-fermented soybeans. The antioxidant activity and EGT of P. cornucopiae-fermented soybeans were higher than those of P. ostreatus, suggesting that EGT was responsible for the increase in the antioxidant activity of P. cornucopiae-fermented soybeans.

著者

Tie-Zhi Liu Li Liu Jing Wen Shu-Yan Liu

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.64, no.6, pp.150-155, 2023-10-27 (Released:2023-11-20)

参考文献数

26

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A powdery mildew was found on Leontopodium leontopodioides (Asteraceae) in China. Phylogenetic analyses using a combination of internal transcribed spacer and 28S rDNA sequences showed that this species, which clusters as sister to Neoerysiphe joerstadii, is allied to N. galii, N. geranii, and N. nevoi. This species differs from the closely allied N. joerstadii in the number and size of asci (3-10 asci, 55-75 × 20-40 µm versus 16-32 asci, 40-60 × 20-30 µm). This species is morphologically very similar to N. gnaphalii, but clearly differs from this species in having larger chasmothecia and colorless appendages. Therefore, the powdery mildew on L. leontopodioides is described as N. leontopodii sp. nov.

著者

Carolina Cornejo Tatsuya Otani Nobuhiro Suzuki Ludwig Beenken

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.64, no.5, pp.123-127, 2023-09-30 (Released:2023-09-30)

参考文献数

20

被引用文献数

1

---

Cryphonectria carpinicola is an ascomycetous fungus that has been regularly found in its asexual form on European hornbeam (Carpinus betulus) in Europe over the past two decades. Here we describe the discovery of C. carpinicola in Japan and report for the first time its sexual state on Carpinus species. No symptomatic trees were observed, but stromata were found saprotrophically on broken branches of Carpinus species on the forest floor. The sexual structures of C. carpinicola resembled that of other Cryphonectria species and strongly resembled those of the closely related species C. radicalis. A phylogenetic tree based on the internal transcribed spacer sequences showed monophyly for the Japanese and European isolates of C. carpinicola. Further studies on the distribution and host range of C. carpinicola in Japan and on the life history strategies of this fungus are needed.

著者

Kosuke Izumitsu Kanako Hatoh Takuya Sumita Yuki Kitade Atsushi Morita Chihiro Tanaka Abdul Gafur Akira Ohta Masataka Kawai Takashi Yamanaka Hitoshi Neda Yuko Ota

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.53, no.5, pp.396-401, 2012 (Released:2023-03-31)

被引用文献数

106

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We have optimized a simple and rapid preparation procedure for mushroom DNA extraction from colonies on media or from fruiting bodies for PCR amplification. The protocol combines microwaving twice for 1 min, cooling for 10 min, and centrifuging for 5 min. By using this procedure, more than 100 samples of mushroom DNA can be prepared within 1 h. The DNA obtained can be used for (1) identifying mushroom species by PCR and subsequent sequencing, (2) amplifying low copy number genes (at least 2,000 bp), and (3) screening genetic transformants. This technique will contribute to the mycology of mushroom species.

著者

Miao Liu Uwe Braun Susumu Takamatsu Sarah Hambleton Parivash Shoukouhi Kassandra R. Bisson Keith Hubbard

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.62, no.3, pp.143-165, 2021-05-20 (Released:2021-05-20)

参考文献数

59

被引用文献数

20

---

A taxonomic revision of the hitherto monotypic genus Blumeria was conducted incorporating multi-gene sequence analyses, host preference data and morphological criteria. The sequenced loci included rDNA ITS, partial chitin synthase gene (CHS1), as well as fragments of two unnamed orthologous genes (Bgt-1929, Bgt-4572). The combined evidence led to a reassessment and a new neotypification of B. graminiss. str. (emend.), and the description of seven additional species, viz. B. americana sp. nov. (mainly on hosts of the Triticeae), B. avenae sp. nov. (on Avena spp.), B. bromi-cathartici sp. nov. (on Bromus catharticus), B. bulbigera comb. nov. (on Bromus spp.), B. dactylidis sp. nov. (on Dactylis glomerata as the main host, but also on various other hosts), B. graminicola sp. nov. (on Poa spp. as principal hosts, but also on various other hosts), and B. hordei sp. nov. (on Hordeum spp.). Synonyms were assessed, some were lectotypified, and questionable names previously associated with powdery mildew on monocots were discussed although their identities remained unresolved. Keys to the described species were developed.

著者

Akihiko Kinoshita Kohei Yamamoto Toshiyuki Tainaka Toshifumi Handa Akiyoshi Yamada

出版者

The Mycological Society of Japan

雑誌

Mycoscience (ISSN:13403540)

巻号頁・発行日

vol.63, no.1, pp.26-32, 2022-01-20 (Released:2022-01-20)

参考文献数

24

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We describe a new truffle species, Tuber torulosum, based on molecular and morphological analyses. This species forms a single globose ascospore per ascus, pale yellow in color, as do Japanese T. flavidosporum and Chinese T. turmericum and T. xanthomonosporum in the Japonicum clade of the Tuber phylogeny. However, it can be distinguished from them microscopically by its whitish tomentose mycelium that partially covers the ascoma surface and the mesh size of its spore ornamentation. Cystidia are moniliform and yellowish to reddish. Molecular phylogenetic analysis using the internal transcribed spacer and partial large subunit regions of ribosomal DNA also supports T. torulosum as a distinct species. On the basis of our results, we provide a key to species in the Japonicum clade.