Conditions for fruit body formation in the white rot basidiomycete Phanerochaete chrysosporium

In Phanerochaete chrysosporium fruit body formations is subject to strong catabolite repression by glucose in the presence of physiological levels of nitrogen. Walseth cellulose was found to be the best source of carbon for the induction of fruit body and consequent basidiospore synthesis. Ejected basidiospores collected from cultures grown under these conditions for two weeks are contaminated with neither conidia nor mycelial fragments and are therefore suitable for genetic analysis of recombination. Under conditions of nitrogen limitation, the glucose catabolite repression of fruit body synthesis was relieved. Exogenous adenosine 3,5-monophosphate but not other related nucleotides, also relieved glucose catabolite repression of fruit body formation.     

An electrophoretic approach to Basidiomycetes taxonomy: Intraspecific variability,varieties, ecological influences

Abstract

Basidiospores of several Basidiomycetes species were treated with electrophoretic techniques, comparing the different protein fractions of the soluble component of the spores wall. The electrophoretic data were elaborated to obtain dendrograms indicating the similarity degree. The method was set up and tested for its validity. The technique showed that the degree of variability within the observed species escaped any generalization, covering a broad range; it was possible to identify the varieties in dendrograms of species grown in the same/different geographical zones; the growing environment and the symbiotic host often influenced the electrophoretic pattern of the spore wall proteins and resulted in dendrograms reflecting the ecological conditions.

Abbreviations: ACP, acid phosphatases; EST, esterases; UPGMA, unweighed pair‐group method using arithmetical average     

猪肚菇担孢子交配型的分析

以3个不同的猪肚菇菌株为材料,采用三轮杂交系统研究了其担孢子的交配型。显微镜观察表明,1个担子上着生有4个担孢子。交配型测定结果表明,猪肚菇属四极性异宗结合。χ2测验结果显示,2个菌株的4种交配型孢子单核体的比例符合1:1:1:1的分离规律,1个菌株的担孢子交配型不呈预期的分离比。     

中国的球盖菇科(三)沿丝伞属

通过对吉林农业大学菌物研究所标本馆(HMJAU)、中国科学院微生物研究所菌物标本馆(HMAS)、中国科学院昆明植物研究所标本馆隐花植物标本室(HKAS)和广东微生物研究所标本馆(HMIGD)的105份标本的宏观形态和微观结构的观察,共报道中国沿丝伞属(NaematolomaP.Karsten)真菌6种,其中1个拟定新种,即圆盘沿丝伞(拟)(Naematoloma discodium Meng T.X.et Tolgor);1个中国新记录种,即亚绿沿丝伞[Naematolo-ma subviride(Berk.&Curt.)Smith A.H.];内蒙古、吉林、江西、西藏新记录种烟色沿丝伞[Naematoloma capnoides(Fr.)P.Karsten]和内蒙古、四川新记录种亚砖红沿丝伞[Naematoloma sublateritium(Fr.)P.Karsten]。     

Indoor air quality in schools: exposure to fungal allergens

This study examined indoor air quality within schools in Kansas City, Spokane, Santa Fe, and Orlando. Air sampling was undertaken with both Andersen Single Stage Samplers and Burkard Personal Air Samplers. The data show a wide range of indoor exposures ranging from less than 100 colony forming units (CFU/m³) for viable fungi and 100 spores/m³ for total spores in Spokane and Santa Fe to concentrations over 6000 CFU/m³ for viable fungi and 15 000 spores/m³ for total fungi in Orlando and Kansas City, respectively. In the majority of sites the indoor airspora reflected the outdoor taxa withCladosporium the most abundant genus identified; however, several indoor locations had elevated levels ofPenicillium andAspergillus indicating possible sources of indoor contamination. Airborne basidiospores and smut spores were also fairly abundant in the schools and were among the top five taxa identified. The data also indicated that the airborne concentrations vary significantly during the day and between classrooms within each school. Continued studies in schools are needed to fully assess both the exposure levels and the clinical significance to atopic children allergic to these spores.     

Airborne basidiospores in the atmosphere of Seville (South Spain)

Basidiomycetes produce large quantities of spores that are dispersed by the wind over long distances. Some species can release billions of spores in a day, many of which are important aeroallergens associated with asthma and allergic rhinitis. The results of a survey carried out in the city of Seville during two consecutive years, using a Hirst-type spore trap, showed that airborne basidiospores are present throughout the year, although there is a certain seasonal distribution, with the highest average concentration occurring in November (23,586 basidiospores). Eighteen different types of basidiospores were identified, with Coprinus and Ustilago being the most frequent, followed in descending order of abundance by Agaricus, Phylacteria, Boletaceae, Ganoderma, Cortinarius, Calvatia, Agrocybe, Bovista and Puccinia; the remaining spore types comprised less than 1% of the total basidiospore count.     

Gymnopilus maritimus (Basidiomycota, Agaricales), a new species from coastal psammophilous plant communities of northern Sardinia, Italy, and notes on G. arenophilus

The new species Gymnopilus maritimus is described from coastal plant communities of Juncus maritimus, growing on sandy soil or on decaying plants, from northwestern Sardinia (Italy). The distinguishing features of G. maritimus are: (1) an unusual habitat, (2) robust basidiomata, (3) mild taste, and (4) big and strongly warted spores. The new species is compared with the micromorphologically similar species G. fulgens sensu auct. Brit. p.p. and the biogeographically and ecologically similar species G. arenophilus, as well as with other European species. A photograph of fresh material, drawings of the main micromorphological features, and FESEM and optical microscope microphotographs of basidiospores are added. Furthermore, some notes on micromorphological characters of G. arenophilus are presented and its distribution area enlarged with a record from France. A key for the European species of Gymnopilus morphologically, ecologically, and/or biogeographically related to G. maritimus is presented. The phylogeny inferred from ITS rDNA sequences revealed that G. maritimus represents an independent species and that it is not related to G. arenophilus or G. fulgens. It is the sister group of the clade containing G. imperialis and G. spectabilis, but with a bootstrap support below 50%. The characters shared by the species in this clade are: (1) robust basidiomata, (2) pileus fibrillose or scaly-fibrillose, and (3) spores longer than 8 μm, dextrinoid and strongly warted. Gymnopilus imperialis and G. spectabilis differ by the basidiomata with membranous ring in the stem, living on conifers or decaying wood, and having narrower or wider spores, respectively. Taxonomical novelties: Gymnopilus maritimus Contu, Guzm.-Dáv., A. Ortega & Vizzini     

Pathway analysis of radiation-sensitive meiotic mutants ofCoprinus cinereus

We have isolated 37 radiation-sensitive mutants of the basidiomyceteCoprinus cinereus. Each mutation is recessive, and the collection defines at least ten complementation groups for survival of gamma irradiation. Four complementation groups define the genesrad3, rad9, rad11 andrad12, which are required both for survival of gamma irradiation and for meiosis. Mutants in each of these four groups fail to complete meiosis and produce mushrooms with greatly reduced numbers of viable spores. Propidium iodide staining of meiotic nuclei showed a characteristic terminal appearance for each mutant: few cells of any of the meiotic mutants progress beyond prophase I, and both condensation and fragmentation or dispersal of meiotic chromatin are frequently observed. Scanning electron micrographs showed that the meiotic mutants make varying numbers (0–6) of basidiospore initials and that few of these initials develop into mature spores. When initials are present they are always symmetrically arrayed on the basidium, regardless of initial number. In quantitative measurements of gamma ray sensitivity, double mutants of every tested combination ofrad3, rad9, rad11 andrad12 consistently showed the same gamma ray sensitivity as the more sensitive single mutant parent of the cross. Therefore, these four genes are in the same pathway for the repair of gamma radiation damage, and this pathway also represents one or more functions essential for meiosis.     

Forecasting spore concentrations: A time series approach

Fungal basidiospores andCladosporium spores are the two most numerous spore types in the air of Dublin and its surroundings. They are known to have allergenic components, and the aim of the study described here is to develop a predictive model for these spores. A very simple model, which combines an estimated diurnal rhythm with a simple, one-parameter time series model, provided golld short-term forecasts. The one-step prediction error variance was reduced by 88% forCladosporium spores and by 98% for basidiospores.     

Meiosis,basidiospore development and post-meiotic mitosis in the basidiomycete,Phallus impudicus

The meiotic spindles of Phallus impudicus had a similar ultrastructure to those seen in other basidiomycetes. After meiosis the basidal apex differentiated to form a number of broadly based protuberances which subsequently developed into basidiospores (up to 9 per basidium). The nuclei then underwent a post-meiotic mitosis within the cytoplasm of each basidiospore. After this mitosis one nucleus remained in the basidiospore and a complete septum developed at the base. The significance of this arrangement of meiosis, spore production and post-meiotic mitosis is discussed with respect to the taxonomy and life cycle of this unusual basidiomycete.