Mycena cupulicola sp. nov. and M. adscendens var. carpophila, new to Japan, are described and illustrated. The former is characterized by having lageniform caulocystidia with a slightly thick-walled broadened base and no cheilocystidia. The latter is characterized by having a white pileus up to 1 mm in diameter and narrowly conical caulocystidia. Mycena cryptomeriicola was confirmed to have inamyloid basoidiospores.
Field observations and inoculation experiments revealed that Uromyces appendiculatus var. azukicola has an autoecious and macrocyclic life cycle and produces spermogonia, aecia, uredinia, and telia on Vigna angularis var. angularis and V. angularis var. nipponensis. From inoculation experiments, it was suggested that this rust fungus has different host relationships from other varieties. Morphological examinations revealed that the characteristics of urediniospores and teliospores are different among varieties, although aeciospores are morphologically similar to each other.
Genetic differences among Agaricus blazei strains were investigated using somatic incompatibility testing, isozyme analysis, restriction fragment length polymorphism (RFLP) analysis of mitochondrial DNA (mtDNA), and random amplified polymorphic DNA (RAPD) analysis. Eight strains, one cultivated strain from Brazil and seven from Japan, were used in this study. Somatic incompatibility interactions were observed between the Brazilian cultivated strain and the Japanese strains. The Brazilian cultivated strain had its own distinct patterns of esterase isozyme and mtDNA RFLP, but all seven Japanese cultivated strains showed identical patterns. When the RAPD patterns, obtained using eight primers, were compared the eight strains had their own distinct RAPD profiles. Distance values were calculated between all pairs of the strains based on presence or absence of individual RAPD bands, and a dendrogram was constructed by unweighted pair-group method with arithmetic clustering (UPGMA) analysis. Seven Japanese cultivated strains were grouped to each other, and this group was finally linked to the Brazilian cultivated strain. Based on these results, the degree of genetic variation among the A. blazei strains used is discussed.
To examine the colonization of living leaves from buds and twigs by phyllosphere fungi of Japanese beech, the mycobiota were investigated on buds and twigs and on leaves covered with well-ventilated bags before budbreak. Ten phyllosphere fungi were isolated from rolled-up leaves within buds, bud scales, and twigs. However, frequencies of phyllosphere fungi on expanded leaves were reduced markedly when the buds were covered with well-ventilated bags before budbreak compared to the leaves that were not covered. This observation suggests that invasion of the fungi to the leaves from buds and twigs may be possible but is not the main route. Horizontal transmission may be common in endophytes and epiphytes of beech leaves. Phyllosphere mycobiota were then compared between sun and shade leaves. Of 13 species recorded as phyllosphere fungi, the frequencies of 2 species were lower and those of 3 species were higher in sun leaves than in shade leaves. Frequencies of the other 8 phyllosphere species were not different between sun and shade leaves. This result indicates that the colonization of leaves by some phyllosphere fungi was affected by the microenvironmental conditions on leaf surfaces.
The coelomycete Dwiroopa was determined to be the correct genus for Harknessia lythri, and a new combination is made for this species. The type species of Dwiroopa, D. ramya, is redescribed and illustrated based on the type specimen for which a lectotype is designated. A key to the two species of Dwiroopa is presented along with a discussion of their similarities and differences. The genus Dwiroopa is distinguished from Harknessia by conidial characteristics. In Dwiroopa the macroconidia have widely spaced, longitudinal slits around the conidia and lack a basal appendage, whereas in Harknessia the macroconidia are smooth or have closely spaced, longitudinal slits on only one side of the conidia and often have a true basal appendage. Both Dwiroopa and Harknessia are included in the Diaporthales.
A powdery mildew fungus on leaves of Dalbergia cultrata var. cultrata (Fabaceae) collected at the Queen Sirikit Botanical Garden in northern Thailand is proven to be a new species of the genus Brasiliomyces and is described as B. chiangmaiensis sp. nov. with light and SEM micrographs. Differences in known Brasiliomyces species are discussed, and a key to species of this genus is provided.
Identifications were made by type examinations for 27 species of polypores described by Corner. Roseofavolus gen. nov. is proposed, typified by Grifola eos. The following new combinations are proposed: Amylocystis unicolor, Antrodiella xanthochroa, Cristelloporia pahangensis, C. rutilantiformis, Roseofavolus eos, Tyromyces armeniacus, T. olivascens, and Wrightoporia solomonensis. Hapalopilus rubescens is accepted in the original genus. The following species were already combined with the proper genus: Stecchericium gyroporum and S. trametoides. The following species are synonyms: Tyromyces sublamellatus, a synonym of Abortiporus roseus; T. subradiatus, a synonym of Daedaleopsis conchiformis; T. subroseiporus, a synonym of Fomitopsis scorteus; T. subtrimiticus, a synonym of Fomitopsis spraguei; T. sulphureiceps, a synonym of Antrodiella flava; and Loweporus corticicola, a synonym of C. rutilantiformis. The following species are dubious because of their poor or sterile conditions: Cristelloporia trimitica, Loweporus castaneus, Tyromyces subrubescens, and T. tristaniae. No authentic specimens were traced for Ischnoderma brunneipurpureum, I. friabile, I. solomonense, Loweporus ochraceicinctus, L. pileoliferus, Stecchericium trimiticum, and Tyromyces xanthophaes. Descriptions and line drawings are given for little-known species.
Cell cycle progression of Cryptococcus neoformans was studied for cells grown exponentially at 15°, 24°, and 30°C. Except for speed, cell cycle progression was similar. In particular, budding occurred relatively soon after initiation of DNA synthesis at 15°, 24°, and 30°C. After growth temperature was shifted from 15° to 30°C, cells were transiently arrested before initiation of DNA synthesis. Thus, similar to Saccharomyces cerevisiae, “Start” was the main susceptible cell cycle controlling point in C. neoformans. However, after spontaneous release from arrest as above, cells were further arrested in the unbudded state. Thus, the timing of budding was delayed just before the G2 phase, or even until after entering the G2 phase, but it was also transient, and 5 h after the shift buds emerged relatively soon after initiation of DNA synthesis. Thus, C. neoformans cells can respond adaptively to mild stress by delaying budding. The existence of the second susceptible cell cycle control point, i.e., budding, appears to endow C. neoformans with a unique characteristic of stronger inhibition of multiplication than growth. A model of the C. neoformans cell cycle is also presented.
In the course of a survey on plant diseases and their pathogenic fungi in the Nansei Islands, some noteworthy fungi were collected. Among them, four fungi newly found in Japan were described with some mycological and pathological notes. These species are Septoria gardeniae Savelli, causing circular leaf spot of Gardenia; Phyllosticta cordylinophila Young apud Stevens, causing brown leaf spot of Cordyline; Phyllosticta drummondii Vanef et van der Aa, causing brown needle blight of Araucaria; and Phyllachora minuta Hennings, causing tar spot of Hibiscus.
In 1998, Verticillium sp. (CE98Vt1 and CE98Vt2) were isolated from discolored vascular structures of potato tubers sold at a market in Chiba Prefecture. These isolates were identified as Verticillium tricorpus on the basis of cultural and morphological characteristics and PCR diagnosis. This observed vascular discoloration of the potato tuber was demonstrated in three cultivars (Touya, Toyoshiro, and Waseshiro) among eight cultivars by inoculation to seedlings. External and internal symptoms of these isolates were not distinct in potato plants. The virulence of these isolates to potato was very low as compared with Verticillium dahliae. These two isolates were not pathogenic to Chinese cabbage, eggplant, green pepper, larkspur, parsley, snapdragon, soybean, tobacco, and tomato. This is the first report of V. tricorpus from potato in Japan.