A rust fungus found on cultivars of Kalanchoe blossfeldiana (Crassulaceae) is described as a new species, Aecidium kalanchoe sp. nov., and compared to the other described rusts on members of the Crassulaceae. Only one other rust is known to parasitize Kalanchoe spp. A DNA sequence of A. kalanchoe suggests that the teleomorph is related to Puccinia.

The presence of the 1,8-dihydroxynaphthalene (DHN) melanin biosynthesis pathway was demonstrated in several sapstain fungi including Ceratocystis and Ophiostoma, using both chemical inhibitors and molecular techniques. The inhibitor compounds tricyclazole and carpropamid effectively reduced pigmentation at low concentrations in all tested fungal species, but also lead to growth inhibition at higher concentrations. The inhibitor cerulenin prevented fungal growth in all tested fungi at all tested concentrations, likely due to its inhibitory effect on another enzyme, the metabolically critical fatty acid synthase. Partial DNA sequences for the gene encoding scytalone dehydratase (SD) were obtained from species of Ceratocystis and Ophiostoma and found to have homology with known respective DHN-SD gene sequences. Sequence analysis of the partial SD amino acid sequences showed greater than 80% similarity among the sapstain species, and corresponded well with known phylogenies of sapstain fungi based on rDNA sequences. Aside from the work carried out on the isolate O. floccosum 387N, this is the first known documentation of the melanin pigmentation pathway used by species of the sapstain fungi Ceratocystis, Leptographium and Ophiostoma. Furthermore, since no fungus has ever been found, to our knowledge, to have more than one melanin synthesis pathway, we can state that these species are likely only to use the DHN pathway for melanin production.

A microsatellite-enriched library was constructed from genomic DNA of Phialophora gregata f. sp. sojae, the causal agent of soybean brown stem rot. Specific oligonucleotide primer pairs were designed to flank individual microsatellite loci, and used in PCR to detect polymorphisms among 118 contemporary and archival isolates of P. gregata from several countries, which represent two distinct, but sympatric populations delineated by rDNA genotypes. In general, low levels of genetic variation were observed and manifested in two ways. First, the number of polymorphic loci was low. Among 24 microsatellite loci screened, four polymorphic loci were detected, and two of them were located on the same clone. Second, the number of alleles in the polymorphic loci was low. Only two alleles were observed in each polymorphic locus. Alleles of the polymorphic microsatellite loci were invariant within, but different between, the two populations of P. gregata. From all evidence available, P. gregata f. sp. sojae exhibits several genetic features characteristic of clonal genetic structure, namely widespread distribution and stability of identical genotypes, absence of recombinant genotypes, and correlation of independent genetic traits including three sets of molecular markers, defoliating and nondefoliating pathotypes, and differential pathogenic fitness.

The objective of the study was to develop methods for the specific and rapid identification of Tuber spp. to aid ecological and taxonomical investigations of Tuber spp. and ectomycorrhizal fungi in general. Antisera raised against Tuber melanosporum, T. magnatum, Boletus edulis and Tricholoma matsutake and monoclonal antibodies produced against T. melanosporum were used to develop various immunological assays such as ELISA, Dot-blot and Western blot. A simple squash Dot-blot was used to visualize mycorrhizal infection of inoculated host plants grown in tube cultures and experimental truffières.

Most antisera reacted strongly with homologous antigens from ascomata or mycelia and mycorrhizal root-tips. Their specificity allowed differentiation between Tuber spp. and other ectomycorrhizal fungi. Differentiation among Tuber spp. was possible by Western blot but not by ELISA or Dot-blot assay. The results suggested that specificity of the antisera was confined to genus level. In two cases specificity was increased by absorption with cross-reactive antigens.

Eleven monoclonal antibodies were produced against T. melanosporum. Two were directed against proteinaceous material, the others probably against various carbohydrate determinants. Unfortunately they could not be used for differentially recognizing T. melanosporum as they all cross-reacted at least with extracts of four other ectomycorrhizal fungi.

We isolated ascospores and conidia of fungi associated with leaf spots common in birch leaves, and prepared mycelial cultures from them. The taxonomic positions of the fungi were determined by analysing morphological characteristics with photomicroscopy. The relationship between the teleomorph and anamorph was tested using random amplified microsatellite fingerprints, in which the variation was not explained by the origin of isolates (e.g. ascospores or conidia). This suggested that the ascospores and conidia would have been produced by the same biological species. In pathogenicity tests birch leaves inoculated with mycelia derived from ascospores developed spots showing that the fungus could be the cause of the leaf spots. The anamorph was isolated from the developing spots. Based on these results and on review of the literature we concluded that the causative agent of the leaf spot disease of birch in Finland is Pyrenopeziza betulicola, the anamorph of which belongs to Cylindrosporium.

Scytalidium thermophilum plays an important role in determining selectivity of compost produced for growing Agaricus bisporus. The objective of this study was to characterise S. thermophilum isolates by random amplified polymorphic DNA (RAPD) analysis and sequence analysis of internally transcribed spacer (ITS) regions of the rDNA, to assess the genetic variation exhibited by this species complex and to compare this with existing morphological and thermogravimetric data. RAPD analysis of 34 isolates from various parts of the world revealed two distinct groups, which could be separated on the basis of the differences in the banding patterns produced with five random primers. Nucleotide sequence analysis of the ITS region, which was ca 536 bp in length, revealed only very minor variation among S. thermophilum isolates examined. Several nucleotide base changes within this region demonstrated variation. Genetic distance values among type 1 and 2 S. thermophilum isolates, as determined by ITS sequence analysis, varied by a value of 0.005%. Molecular analyses carried out in the present study would suggest that isolates within this species complex exhibit genetic differences which correlate well with morphological variation and thermogravimetric data previously determined.

Prosthemium betulinum and Pleomassaria siparia are found in the same sites on birch branches. Single spore cultures of P. siparia produced conidia similar to those of P. betulinum. Restriction analysis of 18S rDNA did not differentiate between P. betulinum and P. siparia. Random amplified microsatellite fingerprints showed a high amount of variation, which was not explained by the origin of cultures. We conclude that P. betulinum is the anamorphic state of P. siparia.

A new ascomycete, Iodosphaeria polygoni sp. nov., is described and illustrated from Taiwan. It is compared with the other known species of Iodosphaeria. A key to species is also given.

Melanographium palmicolum sp. nov. is described and illustrated based on a specimen collected on a decaying rachis of Archontophoenix alexandrae in Hong Kong. It differs from other previously described species of Melanographium by its moderately dense and widely divergent conidiophore fascicles, and the shape and size of its conidia. A key to the eight species currently accepted in the genus is provided, based on the literature.

Puccinia menthae is highly variable, with several varieties and variants within varieties. Two principal groups of races, nominated spearmint rust and peppermint rust, have been recognized according to their host range on commercially-important Mentha species, yet both belong to the same variety, P. menthae var. menthae. Ten collections of P. menthae teliospores from four Mentha species in Victoria, Australia, were examined using light microscopy and SEM. The teliospores from M. spicata, M.×cordifolia and M. suaveolens, all hosts to spearmint rust, were verrucose with two equally-sized cells, whereas those from M.×piperita, host to peppermint rust, were generally smooth-walled, and the apical cell was larger and thicker-walled than the basal cell. Fifteen isolates of P. menthae collected from four Mentha species in Victoria were assessed for genomic variation using RAPD analysis and PCR-generated length polymorphism of the ITS region of rDNA. Six out of 113 RAPD primers amplified reproducible marker profiles, 58 polymorphic bands were scored and simple matching distances were computed between the isolates. UPGMA cluster analysis was used to produce a dendrogram and non-metric multi-dimensional scaling to produce a two-dimensional map of the isolates. The spearmint rust and peppermint rust isolates clustered into two non-overlapping groups, providing good evidence that there is limited gene flow between them. All isolates had the same sized ITS fragments. The taxonomic implications of these results are discussed and it is suggested that the peppermint and spearmint rusts should be accorded separate varietal or specific status.

Ephelis japonica and E. oryzae are biotrophic fungi that form systemic epiphytic associations with warm-season grasses. Ephelis has been recognized as the anamorph of Balansia and Myriogenospora, and a synanamorph of Atkinsonella; all three genera belong to Clavicipitaceae (Ascomycota). The teleomorphs have not been detected for E. japonica and E. oryzae. Balansia oryzae had been regarded as the teleomorph of Ephelis oryzae, however, this teleomorphic name is not validly published for the teleomorph alone (Art. 59·6). We analyzed the sequences of the ITS1, ITS2 and 5·8S rDNA regions of 33 Ephelis isolates from Japan, Korea, China, Nepal and India. Phylogenetic relationships of these isolates were analyzed, together with other clavicipitaceous fungi for which sequences were obtained from GenBank. All Asian Ephelis isolates formed a single cluster, which comprised two subgroups. One subgroup had strong affinity with B. andropogonis, an epibiont of grasses in tropical regions of Asia. The second subgroup had strong affinity with B. discoidea, an epibiont of grasses in the Americas. A close relationship was also shown to B. asperata, another epibiont of grasses of tropical regions of Asia. Our results do not justify the separation of Asian Ephelis epibionts into E. oryzae and E. japonica. E. japonica, established in 1904, ten years prior to the name E. oryzae, is the appropriate name for the asexual Ephelis epibionts of warm season grasses of Asia.

We analysed 40 isolates of species Armillaria. borealis, A. cepistipes, A. gallica, A. mellea, A. ostoyae and A. tabescens, mostly collected in the Czech Republic, by PCR-RFLP of the ITS rRNA genes using the restriction endonucleases AluI, HinfI and MboI. Restriction fragments were analysed by ion-exchange high performance liquid chromatography which proved to be more useful informative, and less time-consuming than classical electrophoresis on agarose gel. The HPLC method enabled detection of some heterozygous strains. HinfI discriminated between all six species. Ten isolates were sequenced to confirm changes in restriction sites found by restriction analysis. Cluster analysis based on the restrictions patterns of restriction endonucleases AluI and HinfI divided the analysed species into three groups. The first and the most distant group contained all A. mellea isolates, the second group was formed by A. tabescens and the third group contained species A. borealis, A. cepistipes, A. gallica and A. ostoyae. The A. tabescens group was very homogenous regardless of the origin of isolates (Czech Republic, France and Finland).

Eight new species of Anthostomella, A. acuminata, A. applanata, A. caffrariae, A. colligata, A. meerensis, A. palmae, A. raphiae and A. spiralis, are described from South Africa. They are compared with similar species and illustrated with differential interference contrast photomicrographs.

Monoclonal antibodies were raised against the mycelium of a litter-decomposing basidiomycete, Mycena galopus, for use in an autecological study of the fungus in forest litter. Two clones (3E12 and 6D8), produced using particulate and whole-cell extracts of the fungus respectively, cross-reacted with several species including other Mycena species, non-Mycena basidiomycetes, zygomycetes and anamorphs or mitosporic fungi. Of these clones, 3E12 appeared to be directed against an unidentified β-glucan and 6D8 against chitin. A third clone (6E1), using as immunogen latex collected in the field from stipes of the basidiomes, was specific to M. galopus mycelium in ELISA and immunofluorescence tests and was probably directed against an unidentified polysaccharide.

Five murine hybridoma cell lines secreting monoclonal antibodies (MAbs) with similar binding specificities were raised to extracts from cyclamen leaves colonized with Ulocladium atrum, a saprotrophic fungus used for biological control of Botrytis cinerea. One of the cell lines produced a MAb, UA–PC3, which was used to develop a quantitative ELISA to determine the biomass of U. atrum in extracts from colonized leaves. The antigen, which is water soluble, was present on the surface of conidia and hyphae and was secreted into culture fluids. Production of the antigen was much greater in vivo than in vitro. Germination of conidia took place in saline buffers at 4 °C after 6 h. To avoid amplification of the antigen in biomass assays of the fungus in extracts from sporulating tissues, coating of microtitre wells in ELISA was reduced to 1 h.

The effect of carbon source on the production of a single extracellular β-glucosidase by Acremonium persicinum was investigated using fast protein liquid chromatography. The enzyme was detected in the medium during growth of the fungus on a wide range of β-glucans, particularly those containing a high proportion of (1→6)-β-linkages. While growth of A. persicinum on gentibiose, cellobiose and laminari-oligosaccharides moderately increased β-glucosidase production, growth on sophorose provoked 10-fold greater levels of this enzyme in the culture medium. Levels of the β-glucosidase were minimal in the presence of even low concentrations of glucose, sucrose, fructose or galactose. The results are consistent with the extracellular A. persicinum β-glucosidase being an inducible enzyme, subject to carbon source control by readily metabolizable sugars, with sophorose possibly directly inducing its synthesis.

Species of Gloniella, Glonium and Gloniopsis from southern South America were studied. A new fungus Glonium colihuae sp. nov., with hysterothecia is described from Argentina, Patagonia; Glonium chusqueae is synonymized with Gloniella typhae; Gloniopsis argentinensis and Glonium costesi are validated, and some comments on the taxonomy and occurrence of Gloniopsis araucana, G. praelonga, Glonium abbreviatum and G. cumingii are presented.

Gilmaniella bambusae sp. nov., from senescent culms of Bambusa tuldoides in Hong Kong, is described and illustrated. It differs from other species of Gilmaniella in having small conidia and conidiogenous cells with a verrucose wall. A key to and a synopsis of the known species of Gilmaniella is provided.

Tuber borchii mycelium (strain 1BO) is able to utilise glucose, fructose or mannitol in the culture medium as a carbohydrate source. Since sugars not only function as a metabolic resource and structural constituent of cells, but also act as important regulators of various processes, we investigated if high sugar concentrations could influence fungal growth and development. The studies performed in this paper revealed that fructose or mannitol used at high concentration (50 g l−1) in the culture medium do not influence the growth and the biochemical responses of fungus but the growth of T. borchii mycelium is subject to glucose repression. In experiments with a high glucose concentration (50 g l−1) and with 2-deoxyglucose, a non-metabolisable glucose analogue, the growth of T. borchii was halved with respect to the control (10 g l−1 of glucose). The morphological and biochemical analyses revealed that the hyphae were metabolically and functionally active, but the activity of mannitol dehydrogenase was reduced to one-third in the high glucose treatment. This is the first evidence of glucose repression of growth and activity in the ascomycetous ectomycorrhizal fungus T. borchii.

Isolates of Tiarosporella parca from needles of Picea abies growing in Lapland, southern Finland, southern Norway and Switzerland were compared with each other by using their combined fatty acid and sterol profiles (FAST) and randomly amplified microsatellite (RAMS) markers.

Nineteen fatty acids and four sterols were recorded, nine of which appeared only at low amounts (<1% of the total amount of extractives). In a discriminant analysis of their FAST-profiles the isolates could be separated into three non-overlapping groups: (i) Lappish and southern Norwegian, (ii) Southern Finnish and (iii) Swiss isolates. The Swiss isolates form the most distinct group with 11 out of 23 extractives significantly different from those of the other geographical populations.

In RAMS analysis two out of five primers tested with ten isolates resulted in polymorphic banding patterns. Using these two primers 26 variable markers in eight size areas were observed which allowed separation of the 39 isolates investigated into 35 different haplotypes. Thus, only four pairs of identical isolates were observed. Determination of the genetic diversity among the isolates revealed that 59% of variation was due to variance within populations, 27% was due to variance between populations within geographical regions and 13% was due to variation between regions.

Hence, both methods show a differentiation of the European T. parca population according to geographical origin.