Comparative studies of Drepanopeziza species pathogenic to poplars established that for each species, holotype and herbarium specimens of D. populorum, D. tremulae and D. punctiformis were morphologically similar. Light and electron microscope studies of apothecia revealed that in radial longitudinal section, in apothecial shape and the hypothecial and epithecial tissues of the three species were similar. In general, ectal and medullary excipular tissues of D. populorum were more strongly developed than those of D. tremulae and D. punctiformis. Asci and ascospores of D. populorum were larger than the other two species but because of overlap were of limited use for species delimitation. In consideration of the established synonymy of the anamorphs of D. tremulae and D. punctiformis namely, Marssonina tremulae and M. brunnea, respectively, and close morphological similarity of their teleomorphs, synonymy of D. tremulae and D. punctiformis is suggested, with D. tremulae having priority. Although not studied, D. populi-albae is believed to be a distinct species. Accordingly, three Drepanopeziza holomorphs are recognised on poplars: D. populi-albae, anamorph=M. castagenei; D. populorum anamorph=M. populi; and D. tremulae, anamorph=M. brunnea.

Coniochaeta polymegasperma sp. nov. is described from hare dung from Sutherland, Orkney and Inverness. With 64-spored asci, it differs from other Coniochaeta spp. with asci with more than eight spores by its much larger spores. Delitschia trichodelitschioides sp. nov. is described from hare dung from Sutherland and Inverness, differing from other Delitschia spp. in its distinctively setose pseudothecial neck.

Phylogeny and biogeography of Lentinula, which includes cultivated shiitake mushrooms, were investigated using parsimony analyses of an expanded nuclear ribosomal DNA dataset. Lentinula occurs in the New World as well as Asia and Australasia. The Asian–Australasian Lentinula populations appear to form a clade, but species limits within this group are controversial. We refer to the entire Asian–Australasian Lentinula clade as shiitake. Thirty-seven wild-collected isolates of shiitake were examined, representing Australia, Borneo, China, Japan, Korea, Nepal, New Zealand, Papua New Guinea (PNG), Tasmania and Thailand. Five isolates of the New World species, L. boryana, were included for rooting purposes. Levels of sequence divergence between North and Central American L. boryana isolates are higher than those between the most divergent shiitake isolates. In shiitake, five independent lineages of rDNA were identified, which we call groups I–V, but relationships among these lineages are not well resolved. Group I includes populations from northeast Asia to the South Pacific. Group II includes populations from PNG, Australia and Tasmania. Group III is limited to New Zealand. Group IV is from PNG. Finally, group V is from eastern China and Nepal. The distribution of rDNA lineages suggests a complex biogeographic history. Although many areas remain unsampled, our results suggest that certain areas have particularly high levels of diversity and should be targeted for further study and conservation.

The effects of varying carbon (glucose), nitrogen ((NH4)2SO4, KNO3) and phosphate (KH2PO4) source on solubilization of insoluble Co3(PO4)2.8H2O, Zn3(PO4)2.2H2O and ZnO by the soil fungus Aspergillus niger were assessed. Solubilization activity was quantified by measuring the clear zones produced around colonies of A. niger growing on solidified mineral salts medium amended with the insoluble metal compounds. Effects of nutrient variation on solubilizing properties were compared using ratios of colony growth rate on the metal compounds (Rm) to control growth rate (Rc) and the rate of extension of the zone of solubilization (Rs) compared to the colony growth rate on the metal compound (Rm), i.e. Rm[ratio ]Rc and Rs[ratio ]Rm. Ratios of solubilization rate to growth rate (Rs[ratio ]Rm) on all the compounds decreased with decreasing glucose concentration; there was no solubilization of ZnO below 60 mm glucose and no solubilization of the metal phosphates below 6 mm glucose. Reducing the concentration of ammonium sulphate in the growth medium decreased Rs[ratio ]Rm but these values were increased when the nitrogen source was nitrate. Reducing the phosphate concentration increased solubilization of Co3(PO4)2 but reduced solubilization of Zn3(PO4)2. These findings demonstrate that manipulation of carbon, nitrogen and phosphate sources in the growth medium, and variation of the form of the nutrient source, can be used to alter the solubilizing ability of A. niger. Whilst, in the natural environment, this response to different nutrient sources allows optimal exploitation of resources, the potential to manipulate nutrients for maximum solubilizing ability may prove beneficial for the optimization of the solubilization of metal compounds with respect to the bioremediation of metal-contaminated wastes and polluted ecosystems. It could also prove useful in other biotechnological applications such as metal recycling and extraction of metals from low-grade ores.

An in vitro screen of 83 isolates of coprophilous fungi revealed that many of them were capable of stimulating growth of Sphaeronaemella fimicola at a distance. When in direct contact with S. fimicola, many (excluding the Zygomycotina) also stimulated the production of perithecia. Species of Coniochaeta, Ryparobius, Thelebolus and Trichobolus were the strongest inducers. These and related genera were also associated with perithecia of S. fimicola on dung collected from the field. Hyphae of many of the strong perithecium inducers and a few non-inducing species were parasitized by necrotrophic intrahyphal growth of S. fimicola. Perithecium formation was stimulated even when parasitism was prevented by separation of growing mycelia of Ryparobius pachyascus and S. fimicola by Cellophane. In contrast, prior growth and removal of R. pachyascus followed by inoculation with S. fimicola caused enhanced growth and asexual reproduction without concomitant perithecium formation.

Crypticola is re-evaluated, following a commentary on the nature of its straminipilous ornamentation, zoosporogenesis and habitat range. Atkinsiella entomophaga is transferred to Crypticola, but because this species was made the type species of Halocrusticida, new names are required for Halocrusticida and species therein (Halodaphnea hamanaensis – type species; H. parasitica, H. awabi, H. okinawaensis, H. panulirata). A new family, the Crypticolaceae, is erected for Crypticola. The family is placed, with reservations, in the Myzocytiopsidales, Peronosporomycetes.

Proliferation of intraradical hyphae of the arbuscular mycorrhizal fungus Glomus fistulosum was observed and measured in surface disinfected mycorrhizal maize root segments in an aseptic cultivation system. The maximum growth of hyphae proliferating from the root segments was observed at pH 6·3, and low concentrations of buffering substances stabilized the pH of the incubation medium (0·9 mm MES, 1 mm BIS-TRIS). The proliferation of intraradical hyphae was not influenced but the germination of chlamydospores of the mycorrhizal fungus was inhibited by an artificial inorganic soil solution at lowest dilutions. The percentage of root segments bearing proliferating hyphae and the growth of hyphae decreased with increasing concentration of phosphate in the incubation medium. All reduced sulphur-containing compounds tested (sulphite, dithionite and metabisulphite) suppressed the proliferation of hyphae completely.

The new combination Thanatephorus obscurus is proposed, based on a study of the type specimen of Ceratobasidium obscurum. The reports of this species as an orchid associate are based on misdeterminations. The unusual gelatinized basidiome of T. obscurus is discussed and compared with that of a new, unnamed taxon from the Cameroon rain forest.

Isolates of Fusarium oxysporum from different habitats were compared with respect to intra- and extracellular isozymes. Five intracellular enzymes: esterase, superoxide dehydrogenase, malate dehydrogenase, dihydrolipoamide dehydrogenase and succinate dehydrogenase were extracted from the mycelium, and four extracellular enzymes: protease, cellulase (endoglucanase), amylase and lipase were obtained from the culture medium. Proteins were separated either by discontinuous PAGE or by IEF, and isozymes were detected by specific staining. The intracellular enzyme data were analysed by an unweighted paired group method analysis (UPGMA), which separated the isolates into three main clusters. The clusters generated from the intracellular enzymes were weakly correlated with the electrophoretic types based on the extracellular enzymes. These results suggest that extracellular enzymes may be of limited value for classification within F. oxysporum.

From 1991 to 1996, Phellinus noxius was collected on 60 host plant species at 136 different sites in Taiwan, and two host plant species at two different sites on Kinmen Island. It was collected mostly on hosts growing in the low elevation plains and hills of western, eastern and southern Taiwan, while it was found on only a few hosts in northern Taiwan and was absent from the high mountain areas. P. noxius was observed on and isolated from 57 woody species, and three annual herbaceous plants. In the field, basidiomes of P. noxius have only been observed on Casuarina equisetifolia, Delonix regia and Ficus microcarpa. A dark brown mycelial mat on the surface of the roots and up the base of stems was used reliably for the field identification of P. noxius. Although P. noxius did not favour a particular soil pH, it was not found in extreme pH conditions. It was found in soils from pH 4 to 9 and most frequently in soil from pH 5 to 8. P. noxius occurred mostly in soils with sand, loamy sand and sandy loam textures.

RFLP, DNA fingerprinting and VCG methods were used to characterize fourteen Verticillium dahliae isolates collected from southwestern Ontario, Canada. The isolates were typed as not pathogenic to tomato (NP), race 1 (avirulent on cvs carrying the Ve resistance gene) or race 2 (virulent on Ve cvs). On the basis of RFLPs, RAPDs, and DNA fingerprints detected by hybridization to a dispersed, repetitive genomic DNA probe, the isolates were classified into five DNA types. Type I included two NP isolates. Type II included four race 2, and three NP isolates. Types III and V were represented by single race 2 and race 1 isolates, respectively. Type IV included one race 2, and two race 1 isolates. Vegetative compatibility was determined for selected NP, race 1, and race 2 isolates of each race type/DNA type combination. Isolates of the same DNA type were compatible, as were type II and III isolates (VCG 4B), and type IV (VCG 2A) and V isolates (VCG 2B). These data show a level of genetic diversity not previously identified in the V. dahliae tomato pathogen population, and suggest multiple origins for the Ontario race 2 pathotype.

Endogone maritima sp. nov. is described and illustrated. This fungus was recovered from around the roots of endomycorrhizal Ammophila arenaria, Corynephorus canescens, Juncus balticus, J. articulatus, and ectomycorrhizal Pinus sylvestris colonizing a deflation hollow of the Słowiński National Park in Poland. Endogone maritima produces sunflower to brownish yellow zygosporangia enveloped by a separable hyphal mantle consisting of interwoven hyphae appearing in section as a dense net. The zygosporangia occur both singly in the soil and in small, non-peridial sporocarps typically containing 2–7 zygosporangia.

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.

Six new species of Puccinia on Baccharis are described: Puccinia basirostrata, P. ecuadorientalis, P. lentapiculata, P. otavalensis and P. quitensis from Ecuador, and P. vulcanicola from Costa Rica. Beside features of telio-, uredinio- and aeciospores, basidiospore morphology yielded important characters for species delimitation.

Primary colonization and the early growth of the mycelium of Agaricus bisporus in compost could be improved to increase the rate of substrate utilization. The production of enzyme activities during the vegetative growth of a commercial strain in compost were determined. N-acetyl-glucosaminidase activity peaked during the first week whereas the activities of polysaccharidases decreased with the replacement of autochthonous micro-organisms by A. bisporus. A low level of water soluble sugars was maintained in compost inoculated with A. bisporus in comparison with a non-inoculated compost. Microbial residues and hemicelluloses appeared to be important nutrient sources during the early growth.

Observations are presented showing that mature thalli of the rumen anaerobic fungal isolate Neocallimastix frontalis strain RE1 attach to cellulose. This process and subsequent development of the thalli have been studied. Thalli matured without attachment and then attached directly by means of rhizoids to the surface of the substrate. This process was quantified by the measurement of attachment of 14C-radiolabelled fungal cells pregrown on [UL-14C]-d-glucose to filter paper. Washed cell suspensions were separated into zoospores and thalli by filtration and the time-course of attachment of each fraction to filter paper strips was determined. Both thalli and zoospores made a significant contribution to the colonization process. It is suggested that the previously unrecognized ability of mature thalli to attach to cellulose could be of importance in the degradation of plant material in the rumen.

After attachment to filter paper the formation of dark brown pigmented sporangia was observed after incubation for periods in excess of 4 d. These had some similarities to resistant sporangia which have been described in aerobic and anaerobic chytrids, but they differed in some important respects. The pigmented cytoplasm retracted, leaving a clear margin within an unthickened cell wall. Histochemical tests showed that the pigment was not melanin and strain RE1 was able to grow and form the pigment in the presence of each of three inhibitors, tricyclazole, PP389 and glyphosate, which block melanin biosynthesis pathways in fungi.

Nine new species of Phanerochaete from Taiwan are described and illustrated: P. argillacea, P. capitata, P. eburnea, P. flavidogrisea, P. fulva, P. hyphocystidiata, P. reflexa, P. rubescens, and P. suballantoidea. A key to 30 species of Phanerochaete from Taiwan is given.

Four DNA sequences (ARSs) that are able to initiate DNA replication in yeast were isolated from mitochondrial DNA of Phytophthora nicotianae and localized on its physical map. Nuclear sequences from P. nicotianae were shown to initiate DNA replication in yeast only very rarely. Minimal regions necessary for replication catalysed by mitochondrial ARSs were delimited by DNase I digestion and sequenced. Transformation efficiencies were estimated for full-length ARS-carrying DNA fragments. Segregation rates and mitotic stabilities in S. cerevisiae were determined for the two shortest subclones of each of the three delimited ARSs. Replication properties of all three ARSs were similar to those of a yeast nuclear ARS sequence. Sequence analysis revealed the presence of many copies of the motif (T/G)ATATTTT, which is related to the ARS core consensus sequences, in all three elements. In two of them, four copies of the motif and its reverse complements were arranged in palindromes. In addition, whole ARS core sequences and long segments consisting exclusively of A and T nucleotides were found in all ARS analysed. These features indicate that an HMG-like (high mobility group) DNA-binding protein similar to ABF2 from yeast may participate in DNA packaging also in non-fungal mitochondrial lineages.

Three new species of Rotiferophthora (R. minutispora, R. amamiensis and R. lacrima) were isolated from samples of soil, rabbit dung and farmland waste in Japan. All species infected bdelloid rotifers and produced dictyochlamydospores in addition to conidia, but their modes of conidiogenesis differed. R. minutispora had small spherical conidia and long tapered conidiogenous cells which formed in verticils around the conidiophores; R. amamiensis had ovoid conidia produced from flask-shaped conidiogenous cells and aphanophialides, and R. lacrima produced long tear-shaped conidia enveloped in a mucoid sheath from short conidiogenous cells produced in a Drechmeria-like formation. A summary table of all known species of Rotiferophthora is shown.

Stratiphoromyces brunneisporus gen. et sp. nov. occurring on decaying petioles of Licuala spp., collected from rain forests in Australia and Brunei, is described and illustrated. It is unique in producing a globose mass of brown, uniseptate, curved, setulate conidia, from percurrently proliferating conidiogenous cells at the apex of solitary, erect, unbranched, brown conidiophores. The genus is briefly compared with Dictyochaeta and other similar hyphomycetes.