A new genus, Brevicollum, is established for two new species, B. hyalosporum on Syzygium samarangense and B. versicolor on Volkameria inermis, in Japan. This genus is characterized by the presence of immersed ascomata with an excentric to central, short cylindrical ostiolar neck, thin ascomatal wall, clavate asci with a shallow ocular chamber, and broadly fusiform, hyaline to pale brown ascospores with a sheath. Molecular phylogenetic analyses based on a combined data set of sequences of 18S and 28S nuc rDNA genes and the second largest subunit of RNA polymerase II (RPB2) revealed that Brevicollum is a member of Neohendersoniaceae (Pleosporales, Dothideomycetes). The genera Brevicollum, Crassiparies, Medicopsis, and Neohendersonia are accepted in Neohendersoniaceae. Revised descriptions of Crassiparies and its type species, C. quadrisporus, are provided based on the holotype and a newly obtained specimen and isolate. An asexual morph of C. quadrisporus is reported for the first time. The nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) phylogenetic tree of the newly collected species (B. hyalosporum, B. versicolor, and C. quadrisporus), and the unnamed or provisionally identified endophytic species, suggests a broader distribution of Brevicollum and Crassiparies species.
The resinicolous fungi Sarea difformis and S. resinae (Sareomycetes) were taxonomically revised on the basis of morphological observations and phylogenetic analyses of the nucleotide sequences of the nSSU-LSU-rpb1-rpb2-mtSSU genes. The results of phylogenetic analyses show that S. difformis and S. resinae are grouped with members of Xylonomycetes. According to the results of phylogenetic analyses and their sexual and asexual morphs resemblance, Sareomycetes is synonymized with Xylonomycetes. Although Tromera has been considered a synonym of Sarea based on the superficial resemblance of the sexual morph, we show that they are distinct genera and Tromera should be resurrected to accommodate T. resinae (= S. resinae). Xylonomycetes was morphologically re-circumscribed to comprise a single family (Xylonaceae) with four genera (Sarea, Trinosporium, Tromera, and Xylona) sharing an endophytic or plant saprobic stage in their lifecycle, ascostroma-type ascomata with paraphysoid, Lecanora-type bitunicate asci, and pycnidial asexual morphs. Phylogenetic analyses based on ITS sequences and environmental DNA (eDNA) implied a worldwide distribution of the species. Although Symbiotaphrinales has been treated as a member of Xylonomycetes in previous studies, it was shown to be phylogenetically, morphologically, and ecologically distinct. We, therefore, treated Symbiotaphrinales as Pezizomycotina incertae sedis.
1 September 2000 in Japanese Journal of Applied Physics
A Bi-Ta multi-seeding layer system is proposed to improve the ferroelectric properties of SrBi2Ta2O9 (SBT) thin films prepared by a sol-gel method for applications to nonvolatile memories. For seeding layers composed of different ratios of Bi to Ta, three different structures were observed after heat treatment at 800°C: γ-Bi2O3, Bi3TaO7 and Bi1.4Ta2O6.75. γ-Bi2O3 with a sillenite structure exhibited a plate-like surface morphology. Bi3TaO7 with a fluorite structure exhibited a flat surface morphology. Bi1.4Ta2O6.75 with a pyrochlore structure exhibited a rough surface morphology. Because a flat surface morphology with a fluorite structure is desirable for a seeding layer, the Bi–Ta seeding layers, with a Bi to Ta ratio equal to 3 to 1, were used as multi-seeding layers. When the seeding layers were sandwiched between SBT thin films, multi-seeding layers provided, after heat treatment at 800°C, a higher degree of crystal orientation in the a- or b-axis direction than a simple SBT thin film without seeding layers. Orientation in the a- or b-axis direction is desirable for SBT thin films to obtain improved ferroelectric properties, especially high remanent polarization values. The SBT thin film with Bi–Ta multi-seeding layers was found to have higher saturation characteristics than that without seeding layers, which suggests that the former type of SBT thin film has a good potential for low-voltage operation. The multi-seeding method is thus effective for improving ferroelectric properties of SBT thin films for nonvolatile memories.
The diversity of sporocarp-inhabiting fungi (SCIF) was examined using six samples of xylarialean fungi from two different forests in Ibaraki Prefecture, Japan: a moist forest in the Sakuragawa area and an urban dry forest in the Tsukuba area. These fungi were enumerated using direct observation and dilution plate methods. We obtained 44 isolates, and careful morphological and molecular phylogenetic studies of these isolates revealed that approximately 30% of the operating taxonomic units were undescribed or cryptic species related to known fungi. Although typical mycoparasitic fungi, such as helotialean fungi and Trichoderma spp., were not isolated, the genera Acremonium, Acrodontium, and Simplicillium were detected. Comparisons of SCIF communities between the two forests suggested that the number of isolated species in the Sakuragawa area was lower than that in the Tsukuba area. Soil-borne fungi, such as Aspergillus, Beauveria, Penicillium, and Talaromyces, or polypores/corticioid mushrooms, are frequently detected in the Tsukuba area. Factors affecting SCIF communities in the two forests are discussed. Some noteworthy fungi are briefly described with notes on taxonomy, ecology, and molecular phylogeny.