The phylogenetic position of 50 isolates of the genus Botryosphaeria isolated from 31 host plant species in the 19 families in Japan were analyzed using the combined sequences consisting of partial DNA sequences of rDNA ITS, rpb2, tef1-α, and tub2 regions. As a result, one isolate obtained from Gamblea innovans formed a clade with B. qingyuanensis from China. The other 49 isolates formed a large clade with B. dothidea epitype and its related species. Isolates from Brown blight of walnut and Guignardia canker of Japanese alder formed small subclades of B. dothidea, respectively. It was suggested that the host species and morphological characterstics may be effective in species distinction in this genus. However, the resolution for species distinction by the multi-region analyses adopted in the present study was seemed not to be enough to distinguish B. dothidea species complex. Therefore, we need alternative and additional phylogenetic approach that will divide species complex of B. dothidea. In addition, morphological, biological, and ecological characterization are necessary to reveal probable several species included in the species complex of B. dothidea.

We isolated a sporulation-deficient (sporeless) mutant (B682) of Lentinula edodes using UV-irradiation. The number of basidiospores falling from the mature fruiting body was approximately 1/10,000 of the original (wild-type) strain. Scanning electron microscopy observation showed negligible mature spores on the hymenium surface; however, immature spores were frequently observed. Using HCl-Giemsa staining for basidia of mutant fruiting bodies, eight nuclei were observed in each basidium, suggesting that somatic division of four daughter nuclei occurred after meiosis. Genetic analysis using the tester-population (98115A population) suggested that the sporeless trait resulted from a single dominant factor. Based on next-generation sequencing for original and mutant genomes, single-nucleotide polymorphism (SNP) with nonsense mutation was found, and its inheritance was confirmed in sporeless segregants from the 32D tester-population. From this result, B682 is the first dominant sporeless mutant of L. edodes and is a biological material for studying the sporulation mechanism in basidiomycetes. Furthermore, the SNP is presumably an effective mutation point that enables marker-assisted selection in promoting breeding utilization of sporeless mutation.

We redescribed and illustrated the hyphomycete species, Balaniopsis triangularis, occurring on an inner wall (domestic cypress boards) inside the covering building (shelter) of Mezurashizuka Tumulus (National Historic Site), belonging to the Yakata burial mound group, in Ukiha City, Fukuoka, Japan. This species has not been reported since its original description based on two collections, namely conifer wood in the crawl space of a building in Vancouver City, Canada, and damp plywood in New York City, USA. Our finding in Japan suggests that B. triangularis causes the biodeterioration of woody building materials under indoor conditions.

Pucciniosira cornuta was discovered on Berberis nepaulensis at Doi Suthep-Pui National Park, Chiang Mai Province, Thailand. The fungus is characterized by narrow columnar, peridiate telia composed of catenulate, two-celled teliospores. This paper describes detailed sorus and spore morphology of this fungus, that were not previously reported, and lists published records of the hosts and geographic distribution.

Two helotialean species were collected from the cool-temperate or subarctic wetlands in Japan. Based on the morphological examination of the apothecia, the two species were identified as Dasyscyphella cassandrae and Incrucipulum sulphurellum, which have not been reported in Japan before. Descriptions, micrographs, and line drawings of the two species are provided. In this study, septate ascospores and paraphyses of D. cassandrae were documented for the first time. Furthermore, we assessed whether pure white apothecia and sulfur-colored apothecia of I. sulphurellum coexisted in the fresh state.

Goplana dioscoreae and Phakopsora dioscoreae were found in Thailand. Goplana dioscoreae occurs on Dioscorea bulbifera at Doi Suthep, Chaing Mai Prov., D. wallichii at Takua Pa, Phang Nga Prov., and unidentified Dioscorea plants at Doi Suthep, Chiang Mai Prov. and Thap Satae, Prachuap Khiri Khan Prov. Phakopsora dioscoreae occurs on D. aff. alata, D. bulbifera, and unidentified Dioscorea plants at Doi Suthep, Chiang Mai Prov. Phakopsora dioscoreae was known only from the type material collected in Myanmar in 1972.

Stromatinia rapulum, a plant pathogen of Polygonatum species, was first reported from Japan in 1913. However, its identification is doubtful because the description has clear morphological differences from the original description of S. rapulum. In addition, the host plant was incorrectly identified as “Polygonum multiflorum”, an orthographical confusion with “Polygonatum multiflorum”. We newly collected ascomata of S. rapulum occurring from the rhizomes of planted Polygonatum falcatum in Hokkaido. This is the first report of S. rapulum from Japan with the correctly identified host plant.

Five smut fungi collected in Japan are described here: Pilocintractia fimbristylidicola on Fimbristylis miliacea, Sporisorium manilense on Sacciolepis indica, Tilletia arundinellae on Arundinella hirta, Tilletia vittata on Oplismenus undulatifolius, and Ustilago phragmitis on Phragmites australis. These species are reported in Japan for the first time. Besides, Neovossia moliniae on P. australis is described. This is the second record of this smut fungus in Japan.