Ascospore formation and morphology in two species of the genusErysiphe remaining immature on the living host plant

Erysiphe cumminsiana andE. galeopsidis, which have immature asci in the current season, have been recorded from Japan, but the ascospores of both fungi have not been described. In the present experiments, some observations before and after overwintering were made on the cleistothecia ofE. cumminsiana on three species ofCacalia and two species ofLigularia, andE. galeopsidis onGeranium thunbergii. After overwintering, the former fungus developed six to eight, rarely four spores in an ascus and the latter fungus always four spores in an ascus. Their teleomorphic characteristics including those of ascospores are also described.     

Taxonomy and Phylogeny of Synchaetomella Lunatospora, a New Genus and Species of Synnematous Fungi from Southeast Asia

The anamorphic fungus Synchaetomella lunatospora gen. et sp. nov. is described from a culture isolated from leaf litter in Singapore. The genus is characterized by the production of synnematous conidiomata with brown stipes, phialidic conidiogenesis with terminal and acropleurogenous conidiogenous cells, and falcate, 1-septate conidia, aggregating in white, mucilaginous heads. Its phylogenetic relationships, inferred from the partial nuclear small ribosomal subunit (18S) sequence, are with the coelomycetous genera Sphaerographium, Chaetomella, and Hainesia. However, the order and family affinities of this group are unclear.     

Taxonomy of an anamorphic xylariaceous fungus from a termite nest found together with <Emphasis Type="Italic">Xylaria angulosa</Emphasis>

Two xylariaceous fungi were isolated from a nest of a termite, Odontotermes formosanus, that was incubated in a laboratory after collecting from Iriomote Is., Okinawa Pref., in Japan. One of the two fungi was identified as Xylaria angulosa on the basis of the morphology of branched stroma produced on medium, tiny asci, and ascospores having a germ slit. Another fungus is an anamorphic fungus that produces synnemata up to 50 mm long from which dendritic conidiophores branch out. Unicellular conidia are holoblastically produced on a sympodially proliferating conidiogenous cell. Such morphological characters resemble those of the genus Geniculosporium. However, its distinctive synnema formation and dendritic conidiophores do not assign the fungus to Geniculosporium or other known genera and warrant establishment of a new genus. The phylogenetic tree based on the ITS regions of rDNA shows that the fungus is nested in the cluster of the genus Nemania (Xylariaceae), whose species have mainly Geniculosporium-like anamorphs. We describe here the present anamorphic fungus as Geniculisynnema termiticola gen. et sp. nov., and discuss its phylogenetic and ecological relationships to xylariaceous fungi, especially termiticolous species.     

Torrubiella pruinosa,a teliomorph of an entomopathogenic fungus Hirsutella versicolor of mango hopper (Idioscopus clypealis) from India

Torrubeilla pruinosa, a teliomorph of an anamorphic entomopathogenic fungus Hirsutella versicolor on mango hopper (Idioscopus clypealis) was observed. On the infected mango hopper, tiny pin head signs of ascomata were observed. Ascomata of T. pruinosa is pale brown or tawny brown, crowded, immersed in stroma, wall dark golden brown, 260–320?×?230–260?μm, asci clavate, hyaline and thin walled. The ascospores of T. pruinosa are fusiform, distoseptate with a faint tint of pigmentation, 17.5–25.0?×?5.0–7.5?μm. The anamorph stage of H. versicolor fungal hyphae is hyaline, septate and profusely branched, and conidiogenous (phialides) cells are hyaline, pear-shaped and smooth-walled with single or double sterigmata and rarely, multiple sterigmata. Each sterigmata bears single conidia which are hyaline, oval to pear-shaped.     

<i>Natarajania thailandica</i> sp. nov. (Stilbosporaceae,Diaporthales) from Thailand

A fungus similar to the monotypic genus Natarajania, isolated from dead wood and collected in Thailand, is reported. Analysis of partial ribosomal LSU and a protein coding gene (RPB2) demonstrated that the new isolate belonged to Stilbosporaceae, Diaporthales and genetically different from N. indica. It is unique in producing synnematous conidiophores, smooth-walled conidiogenous cells and a flared collarette but lacks an elongated collar-canal which is distinct in the type species. Therefore, sequence data and morphological traits are used to introduce the new species, Natarajania thailandica.     

Arbuscular fungi and mycorrhizae (Glomales) of the Hel Peninsula,Poland

In the years 1985–1989, the occurrence of arbuscular fungi and mycorrhizae on the Hel Peninsula (Poland) was investigated with the help of 45 soil and root samples collected under 20 plant species of eight families. Except for Zea mays, the other plant species were from uncultivated sites. All soil samples contained spores of arbuscular fungi, of which about 45% were of the genus Glomus. Acaulospora spp. preferred members of the Cupressaceae. Spores of Gigaspora occurred rarely and only in two plant families. Glomus spp. were most frequently associated with plants of the Rosaceae, and species of Scutellospora were found at markedly higher frequencies among roots of plants of the Gramineae and Cupressaceae. A total of 29 spore-forming species and Glomus tenue (a fungus recognizable by its distinctive infections) were found. The most frequently recovered fungus, Glomus tenue, was present in roots of 56.8% of examined plants. Of the spore-forming fungi, the most frequently isolated spores were those of Scutellospora dipurpurascens, then Glomus constrictum, Acaulospora 61, and Glomus microcarpum. The overall spore density in examined samples averaged 99.8 in 100 g dry soil in the range 1 to 547, and was highest in a sample taken from around roots of Festuca arundinacea. The dominant fungi forming spores in sampled soils were Glomus constrictum, Glomus microcarpum, and Scutellospora dipurpurascens. The average species density was 3.9 in 100 g dry soil in the range 1 to 10, and was highest in Corynephorus canescens, Rosa canina, and Thuja occidentalis. Levels of colonization by arbuscular fungi ranged from 0.0 to94.0% (mean 23.3%) of the root length and were highest in Festuca arundinaceae and Zea mays.     

Pleurovularia, a new genus of hyphomycetes proposed for a parasite on leaves of Microstegium sp. (Poaceae)

The hyphomycete Ovularia polliniae, formerly excluded from Ramularia and allied genera and tentatively considered as related to Beniowskia sphaeroidea, was recently collected on leaves of the grass Microstegium sp. in Taiwan. Based on studies with light and transmission electron microscopy, O. polliniae was redescribed. Using type specimens, the taxonomic status of both fungal species was reevaluated. In O. polliniae, the conidiophores emerge directly through the outer cell wall of the host epidermis. They are either sparsely branched at the base or simple and composed of verruculose intercalary and terminal conidiogenous cells that produce conidia through minute, slightly darkened scars. The conidia are solitary, one-celled, obovoid, hyaline, smooth, and often have a large vacuole. By the combination of these characteristics, this fungus differs from similar species of Beniowskia, Ramularia, and Ramulariopsis. The new genus Pleurovularia and the new combination Pleurovularia polliniae are proposed to accommodate this parasite on Microstegium. Received: May 24, 2001 / Accepted: September 3, 2001     

Host–pathogen interaction after infection of Galleria mellonella with the filamentous fungus Beauveria bassiana

The filamentous fungus Beauveria bassiana is a natural pathogen of the greater wax moth Galleria mellonella. Infection with this fungus triggered systemic immune response in G. mellonella; nevertheless, the infection was lethal if spores entered the insect hemocel. We observed melanin deposition in the insect cuticle and walls of air bags, while the invading fungus interrupted tissue continuity. We have shown colonization of muscles, air bags, and finally colonization and complete destruction of the fat body—the main organ responsible for the synthesis of defense molecules in response to infection. This destruction was probably not caused by simple fungal growth, because the fat body was not destroyed during colonization with a human opportunistic pathogen Candida albicans. This may mean that the infecting fungus is able to destroy actively the insect's fat body as part of its virulence mechanism. Finally, we were unable to reduce the extremely high virulence of B. bassiana against G. mellonella by priming of larvae with thermally inactivated fungal spores.     

The Effects of Oligosaccharide and Spores from Aspergillus niger on the Defence Responses of Taxus chinensis Leaves In vitro

Spores and oligosaccharide of a strain of Aspergillus niger, which had been isolated from the inner bark of Taxus chinensis, were used to treat T. chinensis leaves. The spores decreased the dry weight and chlorophyll content of the leaves, but increased their malondialdehyde content; oligosaccharide induced similar but more moderate changes. The changes in soluble protein, phenolic content, and peroxidase and phenylalanine ammonia‐lyase activity were also analysed. Oligosaccharide significantly increased all these, whereas the spores had contrary effects. Results indicate that oligosaccharide, but not the fungal spores, elicited a defence reaction in T. chinensis. Possible reasons for these different effects on T. chinensis leaves in vitro are discussed.     

Sporisorium warambiense sp. nov., a fourth smut fungus on Xerochloa in Australia

Sporisorium warambiense is described and illustrated from the ovaries of Xerochloa laniflora from the Pilbara region of Western Australia. The smut fungus is characterized by sori restricted to the ovaries, presence of three simple, stout, narrowing columellae, dark reddish-brown spore balls, dimorphic spores (darker outer spores and lighter inner spores), and the absence of sterile cells. The differences between Sporisorium warambiense and three other smuts that infect Xerochloa (Sporisorium xerofasciculatum, Tilletia xerochloae, and Ustilago xerochloae), as well as comparable Sporisorium species on other grass genera from the tribe Paniceae are discussed. All Xerochloa smuts are endemic to Australia.     

Detection of arbuscular mycorrhizal fungal spores in the air across different biomes and ecoregions

Aerial dispersal of fungal spores is common, but the role of wind and air movement in dispersal of spores of arbuscular mycorrhizal (AM) fungi is largely unknown. Several studies have examined the possibility of AM fungal spores being moved by wind vectors without observing spores taken from the air environment. For the first time this study observed the presence of AM fungal spores in the air. The frequency of AM fungal spores in the air was determined in six North American biomes composed of 18 ecoregions. Multiple samples were taken from both the air and the soil at each location. AM fungal spores were found in high abundance in the soil (hundreds of spores per gram of soil), however, they were rarely found in the air (most samples contained no AM fungal spores). Furthermore, only the Glomus morphotype was found in the air, whereas spores in the soil were taxomomically more diverse (Glomus, Acaulospora, Gigaspora, Scutellospora morphotypes were observed). The proportion of Glomus spores in the air relative to Glomus spores in the soil was highest in more arid systems, indicating that AM fungi may be more likely to be dispersed in the air in such systems. Nonetheless, the results indicate that the air is not likely a dominant mode of dispersal for AM fungi.     

Fertile fungal spores collected on different faced surfaces in the atmosphere of Giza,Egypt

A quantitative and qualitative survey was carried out for airborne fungus spores coming into contact with horizontally and vertically gravitation sampling oriented surfaces in the atmosphere of Giza city. Czapek Dox agar, malt extract agar, potato dextrose agar and Sabouraud dextrose agar Petri dishes were exposed monthly to the five oriented surfaces of a polystyrene cube, throughout a one-year period. Significant differences (P < 0.01) were observed between the total counts of caught airborne fungi contacting with the horizontal compared to other vertically oriented surfaces. Conversely, there were no significant differences observed between the total catch of airborne fungi using the various sampling media. The results revealed that vertical sampling provides valuable information that may be lost from horizontal sampling alone. A total of 5,053 colonies belonging to 40 fungal organisms were identified. Alternaria (24.26%), Aspergillus (19.2%), Cladosporium (14.5%) and Penicillium (11.43%) were the most predominant fungal genera. Collected fungi were grouped into high, medium, low and rare components depending upon their frequency in the studied atmosphere. Aspergillus niger, Aspergillus parasiticus, Alternaria, Cladosporium and Penicillium were regularly found on all oriented surfaces. However, Arthrobotrys, Biospora, Chaetomium, Pleospora, Trichothecium and Verticillium were rarely found in the air. Positive and/or negative correlations were observed between the total fungal counts and the predominant fungal types with meteorological parameters during sampling days.     

Phylogeny and morphology of Hirsutella tunicata sp. nov. (Ophiocordycipitaceae), a novel mite parasite from Peru

A new species of Hirsutella was isolated from unidentified mites on Petri plates inoculated with soil and root fragments collected from asparagus rhizosphere at Virú, Northern Peru. The fungus differs from other Hirsutella species by an envelope surrounding the conidium, conidia dimension and DNA sequences. In PDA cultures, the mycelium produced aerial hyphae with conidiogenous cells mainly at right angles, occasionally showing a secondary conidiophore. The solitary conidia are cymbiform, slightly apiculate, 5.0–6.0 × 3.0–4.0 μm. Phylogenetic analyses with partial rRNA and β-tubulin gene sequences confirmed the fungus as an Hirsutella (Ophiocordycipitaceae). Closest species shown by maximum likelihood and neighbor-joining trees were H. nodulosa and H. aphidis, from which the new species differs for conidium or conidiogenous cells dimensions, lack of synnemata and host type. A recombination event was also detected in the rRNA of the holotype strain, involving Ophiocordyceps sinensis as major parent and O. cochlidiicola as minor parent. A complement, inverted insertion was also found in its rRNA, involving part of the ITS2 and 5.8S regions, flanked by two short nucleotide arrays. Due to conidia dimension and phylogenetic position, the fungus is described as Hirsutella tunicata sp. nov. A review of mononematous Hirsutella species is provided.     

Incidence of allergenically significant fungal aerosol in a rural bakery of West Bengal,India

The frequency of fungal spores in the air of three different sections of a rural bakery was analyzed using a Burkard personal slide sampler and Andersen two stage viable sampler. In average concentration of spores (No./m³) was 228–26770/m³ and concentration of viable colony forming units (CFU/m³) was 65-2061 CFU/m³. Dominant fungus species both culturable and nonculturable, were species of Aspergillus and Penicillium, Cladosporiumsp., Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Cladosporium cladosporioides, Penicillium citrinum and Alternaria alternata. Seasonal variations in the spore concentrations were clearly observed in case of some fungi. Total culturable mould concentration of different bakery sections sometimes exceeded the acceptable limit for a healthy indoor environment. Antigenic extracts prepared from some dominant culturable fungi showed high level of allergenicity in skin prick tests indicating that they could be responsible for allergic respiratory dysfunction of bakery workers.This revised version was published online in October 2005 with corrections to the Cover Date.     

CONIDIOGENESIS IN CERATOCYSTIS ULMI,CERATOCYSTIS PICEAE,AND GRAPHIUM PENICILLIOIDES

Conidiogenous cells of both the synnematous and mononematous conidiophores in Ceratocystis ulmi and C. piceae develop by sympodial proliferation. Holoblastic conidia are produced on nodules or short denticles from the synnematous conidiogenous cells and on well-defined denticles from the mononematous conidiogenous cells. Graphium penicillioides is characterized by percurrent proliferation of the conidiogenous cells and the conidia are holoblastic and annellidic. A comparison of the type material of G. penicillioides with the lectotype specimen of C. piceae indicates that G. penicillioides is not the conidial state of C. piceae. The method of conidial development in C. ulmi and C. piceae is distinct from that of G. penicillioides, the lectotype species of Graphium; these conidial states are, therefore, placed in a new hyphomycete genus, Pesotum, as the Pesotum state of Ceratocystis ulmi and C. piceae, respectively.     

Molecular phylogeny and morphology of <Emphasis Type="Italic">Ophiocordyceps unituberculata</Emphasis> sp. nov. (Ophiocordycipitaceae), a pathogen of caterpillars (Noctuidae,Lepidoptera) from Yunnan,China

Ophiocordyceps unituberculata, a new insect pathogenic fungus from southwestern China, is described using molecular phylogenetic and morphological data. This fungus differs from other Ophiocordyceps species by its enormously long monophialidic conidiogenous cells and a large periclinal protuberance often growing near the apex of conidiogenous cells, single conidia (lanceolate to fusiform) embedded in mucous sheath, and much larger conidial dimensions. Four-locus (nrSSU, nrLSU, tef-1α and rpb1) and ITS data phylogenetic analyses show that O. unituberculata belongs to the Hirsutella nodulosa clade within the genus Ophiocordyceps of Ophiocordycipitaceae and is a separate clade from other allied species. Molecular phylogeny and morphology both strongly support the distinctiveness of this taxon. The interspecific relationships in the H. nodulosa clade are discussed.     

Caeoma tsukubaense n. sp., a rhododendron rust fungus of Japan and southern Asia, and its relationship to Chrysomyxa rhododendri

A rust fungus found in Japan on Rhododendron kaempferi, R. kiusianum, and R. dauricum has previously been identified as Chrysomyxa rhododendri. Light and scanning electron microscopy of fresh and herbarium materials of the rust fungus, however, show that the spore surface morphology differs from the urediniospores of C. rhododendri, and the spores are slightly smaller. Furthermore, the DNA sequence of the 5′-end of the large subunit of ribosomal DNA differs from that of C. rhododendri by 3%. Telia have not been found; therefore, it is redescribed as a new anamorphic species, Caeoma tsukubaense. Several specimens from North Korea, Tibet, and Nepal bearing a similar rust fungus are also included in the species.Contribution no.193 from the Laboratory of Plant Parasitic Mycology, Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan     

Ultrastructure of Ascodichaena rugosa on beech bark

Ascodichaena rugosa Butin is a corkinhabiting fungus, found frequently on the bark of Fagus sylvatica L. The hyphae of the fungus are distributed solely in the phellem cells, stopping their growth in the last-formed cork cell layer. The cell to cell invasion is effected by penetration hyphae, causing no extensive dissolution of the cork wall. Electron microscopical observations revealed fine structural details of the fruit bodies and of the intracellular hyphae. Of special interest were the finger-like hyaline hyphae in the last-formed layer of cork cells, which are interpreted as haustoria on the basis of the fine structure both of hyphae and host cells. This situation is considered as reflecting a parasitic relationship of Ascodichaena to beech bark. The activity of the fungus led also to the increased production of cork cells, perhaps related to the nutrient supply of the fungus.