This report describes tests with Evan's Blue and MTT (3-[4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide) for the assessment of the viability of rhinosporidial endospores. MTT stained a proportion of the spherical bodies that we regard as the Electron Dense Bodies (EDBs), and the cytoplasm of freshly prepared endospores or ones that were stored at 4 °. Slow-freezing at −20 °C, exposure to 10% formalin, or 0.1% sodium azide of the endospores abolished MTT-staining in both sites. Evan's Blue stained the EDBs and cytoplasm of fresh endospores or those stored at 4 °, and of sodium azide-treated or frozen (−20 °)-thawed endospores. TMRE (tetramethyl-rhodamine ethyl ester) specifically labelled the spherical bodies, supporting the conclusion that these spherical bodies have a mitochondrial-like structure. TMRE-staining was however retained in endospores after their treatment with formalin, sodium azide and slow-freezing while MTT-staining was abolished in all these treated endospores.

These results indicate that EvB and TMRE were capable of revealing the morphological integrity of endospores but failed to identify the metabolic inactivation of the endospores after treatment with formalin, sodium azide or slow-freezing. Only MTT was capable of identifying metabolically active endospores and hence their viability and could prove to be of value in standardizing models of infection.

The morphology of Botryobasidium musaisporum sp. nov., a species with bananiform basidiospores collected in Taiwan, is illustrated, described, and discussed. Only one other Botryobasidium with bananiform basidiospores is known, B. bananisporum described from Africa. A key to 13 Taiwanese Botryobasidium species is provided.

The responses of a number of wood-rotting fungi to culture filtrates of Phellinus contiguus strain GWR, which contained a factor active in self-induction of precocious fruiting, were tested by means of a bioassay. Fruiting of a second isolate of P. contiguus was stimulated by active filtrate and the responses of single basidiospore progeny of GWR ranged from nothing to full fruiting. In similar bioassays culture filtrates from 13 out of 16 single spore progeny stimulated fruiting in GWR but production of active filtrate did not correlate with capacity to respond. Other wood-rotting fungi (two other strains of P. contiguus, P. occidentalis, P. ferruginosus, P. igniarius and P. pini, Phylloporia ribis and Trametes versicolor) produced filtrates capable of inducing fruiting in P. contiguus strain GWR. P. pomaceus, lacked inducing activity and the inactive filtrate of Coniophora puteana was also inhibitory to mycelial growth. It is concluded that production of the factor inducing fruiting in P. contiguus is not species specific.

A new species of the coelomycete genus Rhizosphaera found on needles of Pseudotsuga menziesii in Germany is described, illustrated and compared with related species of the same genus. The conidia of R. pseudotsugae are smaller, especially in diameter, than those of the most similar related species, R. oudemansii, and unlike other Rhizosphaera species the Hormonema state is produced in culture only at temperatures below 18 °C.

Englerodothis oleae and Lepteutypa tropicalis spp. nov., Pellucida pendulina gen. et sp. nov., and Pseudorhynchia mauritiana sp. nov., collected from the Mauritian native plants Cordemoya integrifolia, Olea lancea and species of Pandanus, are described, illustrated and compared with related taxa. A key is provided to the currently accepted species of Lepteutypa.

Eight strains of the mycoparasite Coniothyrium minitans were analysed for intraspecific variation by three different approaches: analysis of morpho-physiological characteristics; random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) analysis of the genomic DNA. A high variability in colony colour, gross morphology and conidial size was found depending on strain and culture conditions. All individual strains could be distinguished using the three type of analyses. However, a close correspondence between RAPD, AFLP patterns and morpho-physiological characteristics of C. minitans strains was not observed. Our results suggest AFLP analysis constituted a more efficient and reliable tool than RAPD analysis or morpho-physiological studies to detect intraspecific variability in C. minitans and to follow its fate after application in the field.

The presence of an ovarian stage in the life-cycle of the Harpellales observed during an ecological study of the Trichomycetes associated with simuliid egg masses in the UK is reported. The ovarian stage was observed to develop zygospores that are morphologically similar to those produced by the midgut species Harpella melusinae in the host larva. Morphological characteristics and the possible developmental stages of this propagule are described using scanning electron microscopy. The discovery of this stage suggests that chlamydospores may play an important role in the life-cycle of the Trichomycetes.

Mass mortality among pond cultured red drum (Sciaenops ocellatus) was observed in Hong Kong. Affected fish were lethargic and lost their appetite but no lesions on the body surface were apparent. Patches of white to brownish cottony growth on the gills of affected fish were observed and microscopic examination revealed mats of hyaline mycelia with mature zoosporangia and oogonia which were identified as Saprolegnia diclina. During induced sporulation, production of primary and secondary zoospores, oogonia, and antheridia were observed. A physiological study of the growth and sporulation of a representative isolate determined its optimum growth requirements. The isolate can grow from pH 4 to 10, in distilled water, at salinities of 5–30‰, and temperatures of 4–30°. Maximum growth was observed at pH 5 and 8–10, at salinities of 5–10‰, and 25–30°. Production of zoosporangia only occurred in distilled water, 5 and 10‰ salinities, with zoospores released in distilled water and 5‰ salinity. Zoospore release was also observed from 4 to 30° with greater abundance at 25 and 30°, while oogonia and antheridia were produced in distilled water and from 5 to 30‰ salinities and at 20–30°.

Zoospore germination and in vitro growth of Phytophthora palmivora were studied in extracts obtained from healthy, wounded and inoculated cacao stem tissues. Extracts from wounded and inoculated stem tissues of IMC 67 (canker resistant genotype) significantly inhibited (P<0·05) zoospore germination and the growth of P. palmivora compared to healthy tissues and the controls. There was no significant difference in the percentage zoospore germination or the growth of the pathogen in the extracts obtained from P 18, SCA 6 and TSH 1076 (susceptible genotypes) and those of the controls, while extracts from ICS 1 and TSH 1188 (moderately resistant genotypes) gave intermediate effects. Also, germ-tube lengths were significantly shorter in IMC 67 extracts than in the controls, moderate in ICS 1 and TSH 1188 extracts and longest in P 18, SCA 6 and TSH 1076 extracts. Tests for antifungal compounds in extracts indicated the presence of phenols. The variation in inhibitory effects of cacao stem extracts on zoospore germination and in vitro growth of P. palmivora can be used as a criterion for selecting cacao genotypes resistant to canker.

Among 46 species of fungi isolated from decaying Ocotea wood, growth differed in response to oxygen stress during a 24 d trial. All fungi grew for one week but during the following 17 d, six different growth responses emerged. In 12 species daily growth rates were initially stimulated, then totally inhibited; in 4 high growth rates were maintained over the 24 d period; in 5 growth rates were similar under both aerobic and anaerobic conditions and then stopped under the latter; in 5 growth rates in both treatments were similar during the whole trial period; in 16 growth was retarded before inhibition, and in 4 growth was retarded without being inhibited. Growth of 91% of the fungi able to produce ligninolytic enzymes was significantly inhibited or retarded in the absence of oxygen. The behaviour of the fungi under oxygen stress conditions is discussed regarding their roles in the colonization and decay of stems of standing Ocotea trees. It is concluded that in standing trees, oxygen stress may exert selective pressure during successive colonisation, and that tolerance to oxygen stress favours Phellinus species and Loweporus inflexibilis in becoming the main climax decay species in Ocotea trees.

Trematosphaeria malaysiana sp. nov. is described based on light microscope and ultrastructural studies. It was found on driftwood, exposed test blocks of Avicennia marina and Rhizophora apiculata, and split twigs of R. apiculata exposed in Kuala Selangor and Morib mangroves, Malaysia. T. malaysiana is characterized by striate, pale brown ascospores and trabeculate pseudoparaphyses. Ascospore cell walls are two layered, an outer thick layer comprising fibrillar mucilaginous material, and an inner bilamellate layer (the inner layer electron-transparent; the outer electron-dense and containing melanin). Both T. malaysiana and Leptosphaeria pelagica were examined at the transmission electron microscope level and their structure compared with that of other bitunicate ascomycetes. T. malaysiana and L. pelagica were similar in that the mucilaginous sheath was the outer most layer, in the former the spore wall was two layered, while in L. pelagica it was three layered. In L. pelagica the spore wall was smooth, while in T. malaysiana it was longitudinally striate.

Two intracellular β-glucosidases, designated P-I and P-II, were found in Aspergillus nidulans. While both enzymes were subject to carbon catabolite repression, they exhibited different degrees of repression. P-I biosynthesis was repressed only by a strongly repressing carbon source such as glucose. By contrast, P-II biosynthesis was repressed by even weakly repressing carbon sources such as acetate or lactose. Repression of both was relieved in the creAd mutant strain, except for the strong repression of P-II biosynthesis which was still repressed by glucose. Thus P-II biosynthesis seems to be more sensitive to carbon catabolite repression than P-I.

Mycological Research News features: Prototaxites: a 400 Myr old giant fossil, a saprotrophic holobasidiomycete or a lichen? and Non-deposit of voucher cultures.

Molecular studies examine the relationships of Rhynchosporium secalis, the species concepts in the Fusarium avenaceum/F. arthrosporioides/F. tricinctum species complex, and the intra- and intersporal genetic diversity of Glomus intraradices. The amino acid sequence of the RAD51 protein in Pleurotus ostreatus has been determined and compared to that in other fungi.

The growth of Fusarium sambucinum is shown to be inhibited by several salts. The effects of moisture and oxygen availability on rhizomorph generation in Armillaria tabescens have been compared with that of other species, and the growth, and appressorial formation in Metarhizium anisopliae was found to be affected by artificial media on which it is grown. The possibilities for the biocontrol of Botrytis cinerea using Ulocladium atrum as an antagonist have also been investigated.

Glycoproteins in the extracellular matrix formed around germ-tubes and appressoria in Colletotrichum lindemuthianum have been examined and compared with those in other species.

Sorosporella is found to be a synonym of Syngliocladium, and a new species with two varieties described from grasshoppers and locusts. The causal agent of a twig dieback of lingonberry is found to be a previously unrecognised Phomopsis species.

The following new scientific names are introduced: Phomopsis columnaris, and Syngliocladium acridiorum spp. nov.; and S. acridiorum var. madagascariensis var. nov.

We hybridized the telomere-associated DNA sequence pTel46 isolated from Coprinus cinereus with Helicobasidium mompa genomic DNA. The hybridized fragments were more sensitive to Bal31 nuclease than those that were not hybridized, suggesting that they were located at the ends of chromosomes in H. mompa. The hybridization profile can be used to estimate chromosome number, since the number of chromosomes in a single basidiospore isolate is about half that in putative parent strains. Thus, single basidiospore and field isolates might be homokaryons and heterokaryons respectively. We found telomere-linked restriction fragment length polymorphisms (RFLPs) in strains of H. mompa isolated from field and individual basidiospores. Thus, this marker appears to be an excellent tool with which to reveal the considerable polymorphism of H. mompa and to identify strains. The RFLP was not found among several strains of the same mycelial compatibility group (MCG) isolated from the same field, suggesting that strains belonging to an MCG group are identical.

The current state of professional mycology in Britain is considered in relation to the intellectual legacy left by the founding father of British mycology, the Reverend M. J. Berkeley (1803–1889). Through a review of Berkeley's life and work, it is suggested that there are many unexpected parallels between British mycology today and in the nineteenth century. Although there are now a considerable number of professional mycologists, support for professional mycology and mycological education is considered to be inadequate and seems in some ways to have advanced little in the past century and a half. It is concluded that above all, the current poor level of support for whole organism studies is the greatest betrayal of Berkeley's legacy.

Alternaria guangxiensis and A. bannaensis on Passiflora spp. collected from China are described and illustrated, and their affinities to closely related species are discussed.

Filosporella pinguis sp. nov., Pachycladina parva sp. nov. and Pleuropedium macrum sp. nov. from stream foam collected in the catchment of the Miramichi River, New Brunswick, are described and illustrated. Filosporella pinguis has a microconidial state. Keys to species in the above genera are provided.

Phellinus formosanus sp. nov. and P. prunicola sp. nov. found growing saprotrophically on decayed stems of Schima superba and Prunus mume, respectively, in Taiwan, are described and illustrated. Cultural characters are described.

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.