This issue of Mycological Research News features: Fungi from coral reefs: a commentary. An obituary of Meinhard M. Moser (1924–2002), doyen of European agaricologists and a Centenary Fellow of the British Mycological Society, is also presented.

Molecular papers in this part include the characterization of an α-L-arabinofuranosidase gene in Penicillium, the proteomomics of development in a Phytophthora, the isolation of differentially expressed genes in Agaricus bisporus, and the demonstration of different genotypes in somatic cells of Armillaria.

Nitrogen utilization by Amanita in Australia is documented, and species antagonistic to Rhizoctonia cerealis are compared enzymatically. Probes to detect Rhizoctonia spp. and Suillus bovinus are also reported. A single Phyllosticta species can live as an endophyte in different plant families, while two morphologically identical Pseudocercospora species on different hosts are molecularly distinct. Two karyotypes occur in the cacoa Crinipellis perniciosa, and new molecular phylogenetic data on the Dermatocapron miniatum and Ophiostoma piceae complexes is presented. New species described include a Phytophthora pathogenic to trees and shrubs in wet sites, and ectomycorrhizal mushrooms from Guyana and India.

The following new scientific names are introduced in this part: Cortinarius conopileus, C. keralensis, C. phlegmophorus, Dermatocarpon taminium, Inocybe ayangannae, I. epidendron, I. lilacinosquamosa, I. pulchella, Phytophthora inundata, Pseudocercospora hibbertiae-asperae, P. platylobi spp. nov.; and D. tenue (syn. D. muhlenbergii var. tenue) comb. nov.

An α-L-arabinofuranosidase gene (abf1) from Penicillium purpurogenum was identified and sequenced. abf1 has an open reading frame of 1518 bp, does not contain introns and codes for a protein of 506 amino acids. The deduced mature protein has a molecular mass of 49.6 KDa, and its sequence is homologous to arabinofuranosidases of glycosyl hydrolase family 54. Southern blots suggest that abf1 is a single copy gene. Putative sequences for the binding of the transcriptional regulators XlnR, CreA, PacC, AlcR and AreA are present in the promoter. Northern-blot analysis shows that abf1 is expressed at neutral but not at alkaline or acidic pH values. The presence of binding sites for regulatory elements in the promoter region has been compared to the genes of other fungal enzymes belonging to the same family. This is the first characterization of an abf gene from a Penicillium species.

Two-dimensional gel electrophoresis was used to analyse stage-specific proteins from Phytophthora palmivora, a pathogen of cocoa and other economically important tropical crops. Approximately 1% of proteins appeared to be specific for each of the mycelial, sporangial, zoospore, cyst and germinated cyst stages of the life-cycle. Three proteins excised from protein gels of P. palmivora were identified as isoforms of actin by database searches to public libraries of Phytophthora infestans. The protein profiles of parallel samples of P. palmivora and P. infestans demonstrated that 30% of proteins precisely co-migrated suggesting that proteomics may be used to examine changes in the specific stages in the life cycles of Phytophthora spp.

The production of cellulases on minimal medium in the edible mushroom Agaricus bisporus is regulated by the carbon source: induced by cellulose and repressed by glucose. In order to isolate cellulose-growth specific sequences, a cDNA library from A. bisporus using suppression subtractive hybridization (SSH) was constructed. Northern blot analysis indicated that a high level of enrichment was achieved; 183 clones were isolated. A preliminary screen with cellulose-specific genes of A. bisporus (cel1, cel2, cel3 and cel4) using Southern hybridization resulted in 28 clones to be cel3, and 5 clones were cel2. The remaining 144 clones were sequenced. Partial sequences of the following genes were found: a β-glucosidase homologue of the blvk gene of Kluyveromyces marxianus; a cellulase homologue of an endoglucanase (avicellase III) of Aspergillus aculeatus, four different xylanases homologue of the xyn genes of different fungi, and one hexose transporter homologue to the hxtA gene of Aspergillus parasiticus. The apparent full-length of two hydrophobins homologue to the abh3 gene of A. bisporus and one histone homologue to the h2a gene of Aspergillus niger were also found. The remaining sequences did not have homology to any known genes.

Somatic cells of Armillaria gallica fruit bodies have been shown to possess different genotypes for molecular-marker and mating-type loci. Here we report experiments on six quantitative traits and demonstrate that somatic cells of fruit bodies possess almost as much genetic variation for growth rate and phenotypic plasticity as do spores, the products of meiosis. Genetically distinct somatic cells therefore have the potential to grow at different rates relative to one another during primordial fruit body formation. This may confer an advantage on all cell lines within a fruit body, not just those that happen to grow better under a particular set of conditions. To our knowledge, genetic variation for fitness-related traits that make up a single genetic individual has not been reported before.

The abilities of isolates of Amanita alboverrucosa, A. conicoverrucosa, A. fuscosquamosa, A. nauseosa, A. ochrophylla, A. pyramidifera, A. roseolamellata, A. xanthocephala and six unidentified Amanita species from eastern Australian temperate sclerophyll forests to utilise a range of inorganic and organic nitrogen sources for growth was examined in axenic liquid cultures. All taxa utilised NH4+ and at least some amino acids readily, while biomass yields on NO3− and histidine were generally low. All taxa were able to utilise bovine serum albumin, but for most taxa biomass yields on this substrate were significantly lower than on NH4+. Significant intraspecific variation in biomass yield was observed on all substrates for taxa for which multiple isolates were screened. As a group, eastern Australian Amanita species thus have the potential to utilise nitrogen from a broad range of organic substrates and this might be important in the nitrogen nutrition of their ectomycorrhizal tree hosts in sclerophyll forests.

The effect of Trichoderma atroviride, T. harzianum, T. longibrachiatum, Clonostachys rosea and Bacillus subtilis isolates applied to wheat seeds against Rhizoctonia cerealis disease of seedlings was investigated under controlled greenhouse conditions. Most Trichoderma isolates significantly reduced the incidence of disease compared with the infected control. Bacillus subtilis was also effective against sharp eyespot, although less active than Trichoderma spp. Interactions between the antagonistic microorganisms and the cereal pathogenic fungus in dual culture experiments on agar growth medium were also studied. Almost all tested antagonists showed competitive activity against R. cerealis: inhibition of its mycelial growth and hyphal interaction. The production of extracellular β-N-acetylhexosaminidase, chitin 1,4-β-chitobiosidase, glucan 1,3-β-glucosidase and protease activity by the tested microorganisms in the presence of cell walls of R. cerealis was then determined. All isolates showed glucosaminidase and chitobiosidase activity. They also produced glucosidase activity, except B. subtilis, whereas only C. rosea, B. subtilis and one isolate of T. harzianum showed detectable levels of protease activity.

Development of specific DNA probes targeting rDNA internal transcribed spacer (ITS-1 or -2) sequences is described for the detection of strains representing uninucleate and binucleate Rhizoctonia spp. and Suillus bovinus. Discriminatory taxon/species-specific target sequences were identified following full length ITS sequence alignment of the test fungal sequences and those of other root associated pathogenic or mycorrhizal fungi. Both long (124–151 bp) and shorter (20–25 bp) probes were generated for assessment in Southern dot blot and liquid hybridization ITS capture-fragment length polymorphism assays. Fungal genomic DNA was presented as the target in dot blot protocols using the longer DIG (digoxigenin) labelled probes whilst the shorter 3′ biotin-labelled oligonucleotide probes were hybridized to PCR amplified full length ITS (ITS1-5.8S-ITS2) in both dot blot and liquid hybridization assays. The optimal hybridization temperatures for dot blot detection also produced maximal target specific signals in the liquid hybridization protocol. The latter protocol was found to be more discriminatory as target fungi were detected on the basis of combined probe hybridization-ITS capture and 5′ Cy-5 labelled ITS length polymorphism analysis (±5 bp) following denaturing sequencing gel electrophoresis in a ALFexpress DNA sequencer.

Different isolates of a foliar endophytic species of Phyllosticta were isolated from different tropical tree species in India to examine genetic variation among the isolates. Internal transcribed spacer-restriction fragment length polymorphism (ITS-RFLP) analysis did not detect any variation among the isolates, suggesting that they all belong to the same species. Sequence data of the ITS region of ribosomal DNA (ITS1 and ITS2, including 5.8S rDNA) supported the identity of the present fungal isolates as P. capitalensis. These results show that P. capitalensis (teleomorph Guignardia endophyllicola?) is an ubiquitous foliar endophyte that can infect tree hosts from different families and habitats.

A species of Pseudocercospora causing foliar lesions on Hibbertia aspera (Dilleniaceae) is morphologically indistinguishable from a species of Pseudocercospora causing foliar lesions on Platylobiumformosum (Fabaceae) from the same locality. In order to assess the degree to which these fungi were related, we sequenced the ribosomal DNA ITS region of cultures derived from single conidial isolates. Cultures were obtained from four specimens of each respective host. The ITS sequences for cultures derived from the same host were identical, with the exception of one isolate that had a 4 bp insert, while the Pseudocercospora species from Hibbertia consistently differed at three bases from the species isolated from Platylobium. These data suggest that two distinct species of Pseudocercospora are represented, and that they probably result from a recent evolutionary divergence. P. platylobii and P. hibbertiae-asperae spp. nov. are described and illustrated.

Pulse-field gel electrophoresis (PFGE) was used to determine the genome size and characterize karyotypic differences in isolates of the cacao biotype of Crinipellis perniciosa (C-biotype). The karyotype analysis of four isolates from Brazil revealed that this biotype could be divided into two genotypes: one presenting six chromosomal bands and the other presenting eight. The size of the chromosomes ranged from 2.7 to 5.3 Mb. The different genotypes correlate with telomere-based PCR analysis. The isolates with six chromosomal bands had two that appeared to be doublets, as shown by densitometric analysis, indicating that the haploid chromosome number for this biotype is eight. The size of the haploid genomes was estimated at approximately 30 Mb by both PFGE and Feulgen-image analysis. DNA hybridization revealed that the rDNA sequences are clustered on a single chromosome and these sequences were located on different chromosomes in an isolate dependent manner. This is the first report of genome size and chromosomal polymorphism for the C-biotype of C. perniciosa.

The phylogeny of the Dermatocarpon miniatum-complex (Verrucariales, lichenized Ascomycota) was studied using nuclear ITS sequence data by both parsimony and Bayesian inference of phylogeny. The ITS region contains a substantial amount of variation which resolves the relationships of terminal groups, while the more basal clades have low support in the analyses. D. miniatum var. miniatum and var. complicatum are polyphyletic, while var. cirsodes is monophyletic but located within the complex, as are both D. leptophyllum and D. linkolae. The variation within the D. miniatum-complex is significantly greater than that between some transatlantic species such as D. luridum and D. meiophyllizum. The new names D. taminium sp. nov. from the Greater Sonoran area, and D. tenue comb. nov. (syn. D. muehlenbergii var. tenue) are introduced.

The Ophiostoma piceae species complex incorporates several economically important species, including serious tree pathogens and agents of bluestain. The species in the complex are morphologically similar, but can be distinguished from each other based on morphology, biology, mating type studies and molecular data. At present, all the species in the complex are considered to be native to the Northern Hemisphere, most of them with a very wide distribution. Only a few sporadic reports of members of the complex are available from the Southern Hemisphere, where they are believed to have been introduced, including New Zealand, Australia, Chile, Brazil and Uruguay. This study aims to confirm the identity of isolates resembling O. piceae originating from three Southern Hemisphere countries, using mating compatibility and rDNA sequencing. Our results show that O. quercus is widely distributed throughout South Africa on both native and exotic hardwoods. O. quercus is also reported for the first time from Brazil, again from a native host. O. floccosum is reported for the first time from South Africa, but from an exotic Pinus sp. These results suggest that species of the O. piceae complex are common in the Southern Hemisphere, and that current views on the origins of especially O. quercus need to be reconsidered.

A Phytophthora pathogen of trees and shrubs previously designated Phytophthora sp. O-group is formally named as P. inundata sp. nov. P. inundata falls within the P. gonapodyides-P. megasperma major ITS Clade 6, its present nearest known relative being P. humicola. It has non-papillate sporangia, fairly large oogonia (average ca 40 μm) with thick walled oospores, amphigynous antheridia, a distinctive colony type, a high optimum temperature for growth of 28–30°C, fast growth at the optimum, and a high upper temperature limit for growth of ca 35–37°. A study of the breeding system of eight P. inundata isolates showed them to be classically heterothallic with A1 and A2 compatibility types. However some P. inundata A1×A2 combinations failed to mate even though the same isolates mated successfully with P. drechsleri testers. Others were ‘silent’ A1s or A2s, unable to produce their own gametangia but able to induce gametangial formation in the opposite sexual compatibility type of another species. This indicates a partial breakdown of the sexual mechanism in the species. Two isolates (one A1 and one A2) were unpredictably and chimaerically self-fertile, suggesting A1+A2 chromosomal heteroploidy. The association of P. inundata with ponds and rivers and with root and collar rots of trees and shrubs after flooding is discussed.

Three new Cortinarius species, Cortinarius conopileus, C. keralensis, and C. phlegmophorus spp. nov., are described from Kerala State in southern India. This is the first record of ectomycorrhizal Cortinarius spp. in the tropical part of India. In addition to distinct morphological characters, the comparative analysis of rDNA ITS sequences of the collections from India and morphologically similar species support the recognition of these taxa as new species. Phylogenetic analyses demonstrate that the three Indian Cortinarius spp. belong to both larger subclades of the genus Cortinarius, clade/cortinarius and clade/telamonia. As supported by morphological and molecular data, C. phlegmophorus belongs to Cortinarius subgen. Myxacium sect. Defibulati. Based on classical morphological characters, both C. keralensis and C. conopileus are representatives of subgen. Telamonia. However, C. conopileus belongs to clade/obtusi, which is a well-supported subclade of clade/cortinarius. Thus, in contrast to classical taxonomy, the clade/obtusi represents an independent evolutionary origin of telamonioid taxa. This result is also reflected by the distinct morphological characters of taxa of clade/obtusi, namely the lamellar trama with ellipsoid inflated hyphae and the presence of cystidia. In contrast, C. keralensis is a typical member of clade/telamonia. Within/telamonia, only relationships of closely related taxa are resolved due to the low genetic divergence found in ITS sequences. Based on morphological and molecular criteria, C. keralensis is a distinct taxon of sect. Saturnini.

Four new species of Inocybe (Agaricales) with pleurocystidia and nodulose spores are recorded from a remote region of rain forest in Guyana, in northeastern South America. All four species of Inocybe occur in association with the arborescent legume genus, Dicymbe (Caesalpiniaceae, tribe Amherstieae). This constitutes the first report of a legume host genus with Inocybe in the neotropics. The new species are I. ayangannae, I. epidendron, I. lilacinosquamosa and I. pulchella. A dichotomous key, morphological descriptions, illustrations, taxonomic commentary, and a discussion of Inocybe in the tropics, are provided.

The leading agaricologist Meinhard M. Moser died on 30 September 2002. He was a Centenary Fellow of the British Mycological Society, and the mentor of numerous students and colleagues throughout the world.