Sawadaea nankinensis comb. nov.: a powdery mildew fungus of Acer buergerianum

The anamorphic state of a powdery mildew on trident maple (Acer buergerianum, Aceraceae), belonging to Sawadaea, has been observed since 1980 in Tokyo and other areas of Japan. Since the autumn of 2003, this fungus has begun to produce chasmothecia in various areas of Japan, which were consistent with Erysiphe nankinensis (= Uncinula nankinensis), but apparently contradictory to the characteristics of the anamorph. Based on a molecular phylogenetic analysis using DNA separately extracted from the anamorph and teleomorph of the fungus on A. buergerianum, it could be demonstrated that sequences of this fungus are sister to Sawadaea. As the anamorph belongs to Oidium subgen. Octagoidium and because of the phylogenetic position within the Sawadaea clade, the new combination Sawadaea nankinensis is proposed for this species. The genus Sawadaea is emended to comprise species with consistently unbranched appendages.     

Invasion of a soft contact lens by Exophiala jeanselmei

The invasion of a soft contact lens by Exophiala jeanselmei is documented. All species in this genus are pathogenic. In humans E. jeanselmei is a recognized cause of mycetoma, phaeohyphomycosis and keratomycosis. This fungus has not been previously listed among lens invaders.     

<Emphasis Type="Italic">Erysiphe fimbriata</Emphasis> sp. nov.: a powdery mildew fungus found on <Emphasis Type="Italic">Carpinus laxiflora</Emphasis>

Ascomata of a powdery mildew-like fungus have been found on Carpinus laxiflora in Tochigi Prefecture of Japan since 2003. The morphological and molecular characteristics of this fungus are reported, and a new species, Erysiphe fimbriata, is proposed. It has large chasmothecia (200–250 μm in diameter) with long (up to 4–5 mm in length), fimbriate appendages arising from the upper half of the chasmothecia and turning upward, and numerous asci (22–38 per chasmothecium). Erysiphe fimbriata is a unique fungus both genetically and morphologically.     

Johnkarlingia,a new genus of the synchytriaceae

A chytridiaceous fungous species was found parasitic in the roots of cauliflower (Brassica oleracea L. var. botrytis) and cabbage (Brassica oleracea L. var. capitata) in the heavy soil fields of Varanasi, U.P. The morphology of resting sporangia and life cycle of the pathogen revealed that no fungus species has hitherto been described befitting its developmental pattern. A new genus Johnkarlingia Pavgi & Singh has been proposed to accommodate the fungus with Johnkarlingia brassicae Singh & Pavgi as its type species. The taxonomy and affinities of the genus are discussed.     

A newLeptographium species associated withTomicus piniperda in south-western China

Tomicus species (Coleoptera: Scolytidae) are serious pests of pines with a wide distribution in Europe, Asia and America. In Yunnan, south-western China,T. piniperda has destroyed more than 0.5 million ha ofPinus yunnanensis in the past 15 years. A blue stain fungus belonging to the genusLeptographium is associated with both the shoot-feeding and trunk-attacking stages of the beetle's life cycle. The fungus is morphologically similar to the anamorph ofOphiostoma crassivaginatum and toL. pyrinum, which are both characterised by short robust conidiophores and hyphae covered by a granular layer. Both these species have been isolated from conifers and are associated with insects. After comparing the fungus fromT. piniperda with similarLeptographium species, using light and scanning electron microscopy, we concluded that it represents a new taxon, which is described here asL. yunnanense sp. nov.     

Nova especie do genero Coelomomyces parasito de ovos de Phlebotomus

Summary A new species of fungus of the genusCoelomomyces, C. ciferrii has been found as endoparasites ofPhlebotomus eggs at Belo Horizonte, Minas Gerais, State in Brazil. It is the first time that the genusCoelomomyces is found in Brasil.The morphological characters of the new species are distinct from other species described.     

Fusarium langsethiae – a HT‐2 and T‐2 Toxins Producer that Needs More Attention

Fusarium langsethiae is a toxigenic fungus that was formally described as a new species in 2004. This fungus was first detailed in the 1990s but was initially referred to as ‘powdery Fusarium poae’ having a spore morphology similar to F. poae but a mycotoxin profile like that of Fusarium sporotrichioides. The species has been isolated from infected oat, wheat and barley grains but has been reported as more problematic in the former crop rather than the latter two. Whilst the epidemiology of F. langsethiae remains unclear, the fungus has been shown to produce high levels of type‐A trichothecenes HT‐2 and T‐2 toxins in small‐grain cereals. HT‐2 and T‐2 toxins are two of the most potent trichothecenes capable of inhibiting protein synthesis in eukaryotes. In this regard, mycotoxin contamination caused by F. langsethiae is clearly a food and feed safety hazard. With the European Commission considering legislation of HT‐2 and T‐2 toxins, more information is required not only on the producer and conditions favouring mycotoxin production, but also on reliable methods of pathogen detection and reduction of cereal contamination. This review describes recent research concerning the known epidemiology of F. langsethiae and suggestions of what needs to be known about the fungus in order to be able to understand and employ measures for preventing its infection and contamination of cereals with HT‐2 and T‐2 toxins.     

Phakopsora schreberae, sp. nov. (Uredinales) occurs onSchrebera swietenioides in India

A rust fungus was described fromSchrebera swietenioides (Oleaceae) collected in India. The fungus possessed densely paraphysate uredinia and subepidermal, crustose telia with irregulary 5–7-layered sessile teliospores. These morphologies are characteristic ofPhakopsora, although noPhakopsora species had been reported from the family Oleaceae. The fungus was concluded to be a new species and a name,Phakopsora schreberae, was proposed for the new species.     

Diploicia canescens (Dicks.) Massal. in Shetland

Summary

The lichenized fungus Diploicia canescens (Dicks.) Massal. has recently been discovered in Shetland. Its world distribution is centred in Europe where it is essentially a western and southern species. Its habitats in Shetland are discussed in comparison with its stations in Orkney and in mainland Britain. It is concluded that the species does not occupy significantly different habitats at the extreme north of its world range, although the precise environmental controls for this species must remain partly unidentified.     

Fungi associated with cellulose decomposition in the tidal mud-flats of Kuwait

Fungi potentially able to decompose cellulose, in the tidal mud-flats of Kuwait, have been investigated. More than 58 species were isolated and their cellulytic ability were tested. Many of the species recorded are well known cellulose decomposers, while for many others the strong cellulytic activity is a new record e.g. Arachniotus dankaliensis, Lasiobolidium orbiculoides, Corynascus sepedonium, and Pesotum sp. Comparison of the frequency of occurrence and cellulytic ability, in all species reported, revealed that there is no coincidence between the two parameters. The high frequency of any fungus does not imply that this fungus is an active cellulose decomposer in the soil and similarly low frequency fungi are not necessarily weak decomposers. It is likely possible, that the competitive saprophytic ability of the fungus which determine its role in the process of cellulose decomposition in the soil rather than its cellulytic ability in pure culture.     

Erysiphe kenjiana (Erysiphales), a new invasive fungus in Europe

An Asian powdery mildew fungus Erysiphe (Uncinula) kenjiana (Erysiphales, Ascomycota) has been found in Ukraine. This is the first record of this fungus in Europe. In 2007, E. kenjiana was collected on four Ulmus species in Kiev. All locations adjoined railways or an airport. Development of E. kenjiana was epiphytotic. This species was not found on elms surveyed at towns situated north-east, east or south of Kiev. The fungus may have been brought directly to Ukraine by rail or air transport. In 2008, the fungus was also collected in Chernihiv situated north-east of Kiev. It is likely that E. kenjiana will spread over all Ukraine and into countries of central and western Europe in 2009 or later. Molecular phylogenetic analyses using D1/D2 domains of the 28S rDNA and ITS sequences revealed that the Ulmaceae-Cannabaceae-parasitic powdery mildews, including E. kenjiana, form a clade with strong supports, suggesting that these species diverged from a single ancestor and expanded their host ranges within the Ulmaceae and allied Cannabaceae. This hypothesis is supported by these species sharing the unique morphology of enlarged apices on their chasmothecial appendages. These fungi formed part of a larger grouping with species on Fagaceae, Nothofagaceae, Rosaceae, and Sapindaceae with strong statistical supports. These results suggest that Uncinula-like powdery mildew fungi on these plant families exhibit close evolutionary relationships with their hosts.     

Observations on chytridiaceous parasites of phanerogams

Summary A hitherto unnoted species of Physoderma on the basal leaves of Juncus pelocarpus Mey. is described. The fungus produces light brown irregularlyplaced spots on the outermost leaves. The endobiotic system is composed in addition to rhizoids of non-septate or 1–2 septate turbinate cells, resting spores and ovate haustorial-bearing cells. Resting spores germinate by dehiscence of a lid and protrusion of a finger-like zoosporangium. No epibiotic stage has as yet been seen. The host range of the fungus has not as yet been studied. This is the first account of a Physoderma on a member of the Juncaceae.Acknowledgement is made to the National Science Foundation for support of this project.     

Tick pathogenicity,thermal tolerance and virus infection in Tolypocladium cylindrosporum

Tolypocladium cylindrosporum is a fungus which has been isolated from soil, from asymptomatic plants as an endophyte and has been shown to be pathogenic to several species of arthropods. The objective of the present work was to study a collection of T. cylindrosporum strains to evaluate the characteristics of this fungus as a bioacaricide. The pathogenicity of five different strains of T. cylindrosporum was tested against two tick species, Ornithodoros erraticus and Ornithodoros moubata. Both tick species were susceptible to all the fungal strains. Mortality was greater for O. erraticus and differed among the five developmental stages of the ticks tested and among the fungal treatments. Mean mortality rates were close to 60% for O. erraticus, similar to those reported for other entomopathogenic fungi used for this purpose. The responses of 11 different strains of the fungus to 22°C and 30°C were also studied. Significant differences in temperature tolerance occurred among the strains and growth inhibition was observed at 30°C. Several mycoviruses were found infecting 5 of the 11 strains. However, no clear relationship was found between the presence of viruses and fungal growth or pathogenicity.     

Isolation ofRoumegueriella rufula as a new record from East Asia

Roumegueriella rufula (Ascomycota; Hypocreales) isolated from a soil sample collected in Taiwan is described as a new record from East Asia. Some observations are recorded, particularly on cultural characteristics of aGliocladium anamorph of this fungus, which has scarcely been reported since Bainier described both ascosporic and conidial forms as species ofGliocladium.     

Phylogeny and evolution of the cryptic fungus‐farming ant genus Myrmicocrypta F. Smith (Hymenoptera: Formicidae) inferred from multilocus data

Fungus‐farming ants (Hymenoptera: Formicidae) have become model systems for exploring questions regarding the evolution of symbiosis. However, robust phylogenetic studies of both the ant agriculturalists and their fungal cultivars are necessary for addressing whether or not observed ant–fungus associations are the result of coevolution and, if so, whether that coevolution has been strict or diffuse. Here we focus on the evolutionary relationships of the species within the ant genus Myrmicocrypta and of their fungal cultivars. The fungus‐farming ant genus Myrmicocrypta was created by Fr. Smith in 1860 based on a single alate queen. Since then, 31 species and subspecies have been described. Until now, the genus has not received any taxonomic treatment and the relationships of the species within the genus have not been tested. Our molecular analyses, using ～40 putative species and six protein‐coding (nuclear and mitochondrial) gene fragments, recover Myrmicocrypta as monophyletic and as the sister group of the genus Mycocepurus Forel. The species M. tuberculata Weber is recovered as the sister to the rest of Myrmicocrypta. The time‐calibrated phylogeny recovers the age of stem group Myrmicocrypta plus its sister group as 45 Ma, whereas the inferred age for the crown group Myrmicocrypta is recovered as 27 Ma. Ancestral character‐state analyses suggest that the ancestor of Myrmicocrypta had scale‐like or squamate hairs and that, although such hairs were once considered diagnostic for the genus, the alternative state of erect simple hairs has evolved at least seven independent times. Ancestral‐state analyses of observed fungal cultivar associations suggest that the most recent common ancestor of Myrmicocrypta cultivated clade 2 fungal species and that switches to clade 1 fungi have occurred at least five times. It is our hope that these results will encourage additional species‐level phylogenies of fungus‐farming ants and their fungal cultivars, which are necessary for understanding the evolutionary processes that gave rise to agriculture in ants and that produced the current diversity of mutualistic ant–fungus interactions.     

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     

Selection and characterization of crystalviolet-and malachite-green-resistant mutants in Volvariella volvacea

Volvariella volvacea, the straw mushroom, has long been considered as a primary homothallic species. However, great variations in monosporous isolates have ralsed a considerable debate on the sexuality pattern of this edible Basidiomycete fungus. Because clamp connection is absent in V. volvacea, the production of genetically marked strains offers a possible means of resolving this problem. In this study, ultraviolet irradiation of basidiospores and mycellal fragments was used to induce crystal-violet- and malachite-green-resistant mutants. Cross-resistance to crystal violet and malachite green occurred between both classes of mutant. The difficulties of inducing mutants in this multinucleate fungus and the significance of mutant markers are discussed.The authors are with the Department of Biology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.     

Identifying the core microbial community in the gut of fungus‐growing termites

Gut microbes play a crucial role in decomposing lignocellulose to fuel termite societies, with protists in the lower termites and prokaryotes in the higher termites providing these services. However, a single basal subfamily of the higher termites, the Macrotermitinae, also domesticated a plant biomass‐degrading fungus (Termitomyces), and how this symbiont acquisition has affected the fungus‐growing termite gut microbiota has remained unclear. The objective of our study was to compare the intestinal bacterial communities of five genera (nine species) of fungus‐growing termites to establish whether or not an ancestral core microbiota has been maintained and characterizes extant lineages. Using 454‐pyrosequencing of the 16S rRNA gene, we show that gut communities have representatives of 26 bacterial phyla and are dominated by Firmicutes, Bacteroidetes, Spirochaetes, Proteobacteria and Synergistetes. A set of 42 genus‐level taxa was present in all termite species and accounted for 56–68% of the species‐specific reads. Gut communities of termites from the same genus were more similar than distantly related species, suggesting that phylogenetic ancestry matters, possibly in connection with specific termite genus‐level ecological niches. Finally, we show that gut communities of fungus‐growing termites are similar to cockroaches, both at the bacterial phylum level and in a comparison of the core Macrotermitinae taxa abundances with representative cockroach, lower termite and higher nonfungus‐growing termites. These results suggest that the obligate association with Termitomyces has forced the bacterial gut communities of the fungus‐growing termites towards a relatively uniform composition with higher similarity to their omnivorous relatives than to more closely related termites.     

Isolation of the transposable element hupfer from the entomopathogenic fungus Beauveria bassiana by insertion mutagenesis of the nitrate reductase structural gene

A transposable element has been isolated from the entomopathogenic fungus Beauveria bassiana by trapping it in the nitrate reductase structural gene, which has been cloned from this species. The element had inserted in the first exon of the nia gene and appeared to have duplicated the sequence TA at the site of insertion. It was 3336 bp long with 30-bp imperfect, inverted, terminal repeats. The element, called hupfer, contained an open reading frame encoding a 321-amino acid protein similar to the IS630- or mariner-Tc1-like transposases, and a residual sequence of about 2 kb which was not significantly similar to any published sequence. There are fewer than five copies of this transposable element present per genome in the fungus. Received: 12 February 1997 / Accepted: 2 May 1997