Considerable taxonomic confusion exists regarding many species of Cantharellus. Several taxa have been classified in either Cantharellus or Craterellus depending on which morphological characters were emphasised. Recent phylogenetic studies based on sequence analyses suggest that some species now classified in Cantharellus should be in Craterellus. We extracted DNA from dried herbarium specimens and amplified, sequenced and cladistically analysed approximately 650 bp of the 5′ end of the nuclear large subunit ribosomal DNA gene. Our data confirm earlier results and provide molecular evidence for the classification of additional Cantharellus species (Ca. ignicolor and Ca. lutescens) within Craterellus. Furthermore, the data enable us to predict that all Leptocantharellus-like species currently classified within Cantharellus are more accurately classified within Craterellus. The species complexes of Cr. tubaeformis and Cr. cornucopioides were also investigated. These analyses did not support the monophyly of Ca. tubaeformis but the hypothesis that colour varieties of Cr. cornucopioides represent separate species was rejected.

Amplified Fragment Length Polymorphism (AFLP) analysis has been used to analyse 100 Australian, European and North American isolates of Leptosphaeria maculans. All isolates had distinct AFLP profiles. They could be classified into five types, which had very few AFLP bands in common and corresponded to classifications made previously on the basis of ability to cause stem cankers on Brassica napus (A group), or inability to do so (B group), and on host range. Four isolates had AFLP profiles completely dissimilar to these groups and to each other. Genetic diversity and geographic differentiation were analysed separately within AFLP types 1 and 2. UPGMA analysis of the 66 AFLP type 1 (A group) isolates using 50 polymorphic bands did not provide evidence for clustering according to geographic origin. Non-metric multidimensional scaling (NMDS) analysis suggested that the Australian and European populations were separate adjacent clusters, while the North American population partially overlapped both the others. This geographic differentiation was supported by Wright's fixation index (Fst) analysis. Three measures of genetic variability between isolates within regions (effective number of alleles, gene diversity, and Shannon index) showed that the North American A group isolates were less diverse than those from Australia and Europe. The 21 AFLP type 2 (B group; NA1 sub-group) isolates did not cluster based on geographic region, which was confirmed by NMDS and Fst analysis. There was a similar degree of genetic diversity within A group and the NA1 sub-group of B group isolates. Unlike other techniques, AFLP analysis can readily discriminate between group B isolates of the L. maculans complex that were previously difficult to classify and also provides individual fingerprints for isolates. Isolates of the A group and of the NA1 sub-group of B group could be also distinguished readily by electrophoretic karyotyping, as the latter isolates had more bands smaller than 1.4 Mb than the A group isolates.

Isolates of Chondrostereum purpureum were characterised on malt agar by rapid growth of white, flat, velvety to cottony mycelium and formation of yellow fruitbody crusts with apiculate basidiospores. The presence of cystidia was diagnostic, but not a reliable taxonomic character. Above 33 °C isolates exhibited a differential growth response and only three failed to grow following 20 d incubation at 36°. Tolerance of high temperature was not correlated with RAPD banding patterns nor geographic origin. All isolates were pathogenic to willow, poplar and apple regardless of their original host, locality or RAPD profiles. No zones of demarcation were observed following infection of wounds by multiple isolates. RAPD banding patterns exhibited considerable diversity, enabling discrimination of isolates with single primers, and this was indicative of the extensive genetic diversity within the NZ population. No RAPD banding combinations specific to host species or locality were observed. An explanation is given for the wide dissemination of C. purpureum isolates throughout NZ.

A molecular and morphological investigation of 35 collections of Daldinia from 11 plant species revealed five taxonomic entities of Daldinia in northern Europe. These include Daldinia concentrica, D. cf. fissa, D. grandis, D. loculata and D. cf. petriniae. D. cf. fissa, D. grandis and D. loculata were found exclusively on burnt wood, but they do not form a monophyletic unit in a phylogenetic tree derived from analysis of the ITS sequence of the ribosomal DNA.

Accurate identification of small-spored Alternaria spp. is challenging because of morphological plasticity under non-standard conditions and the common misapplication of the name A. alternata to a variety of morphologically distinct taxa. A system used by some authors of naming phytotoxigenic alternarias as pathotypes of A. alternata has further clouded the meaning and usefulness of this specific epithet. Two hundred and sixty isolates of small-spored Alternaria, primarily from fruit substrates, were segregated into morphological groups and then subjected to RAPD-PCR analysis using total genomic DNA and three different primers. When cultured under defined conditions, the pattern of sporulation observed at 50 × magnification was predictive of genetic relatedness as determined by cluster analysis of RAPD fragment patterns. In RAPD analyses, morphological groups or species were resolved as distinct branches of the dendrogram: Alternaria gaisen (= A. kikuchiana, A. alternata Japanese pear pathotype, group 2), A. longipes (= A. alternata tobacco pathotype, group 5), the ‘tenuissima’ group (group 5), the arborescens group (group 3) and the ‘infectoria’ group (group 6). Isolates in groups for which there were only a few representatives clustered as a branch. Analysis of RAPD fragment patterns confirmed that when Alternaria isolates are cultured and observed under defined conditions, their phenotypic plasticity is minimized and valid taxonomic separations can be made upon morphological characteristics. We conclude that A. alternata, A. gaisen, A. longipes and other small-spored saprotrophic or perthotrophic taxa are recognizable as morphologically distinct taxa. We suggest that the ‘pathotype’ system of naming small-spored Alternaria taxa confers no predictive value relative to observable morphological and genetic characters, and should be abandoned.

The effect of simulated rain on the persistence of oil and water formulations of conidia of the entomogenous fungus Metarhizium anisopliae when applied to oilseed rape foliage was investigated, using third instar larvae of the mustard beetle (Phaedon cochleariae) as the target host. Rain significantly (P < 0.01) reduced the susceptibility of the beetle larvae to M. anisopliae but the amount of inoculum removed was influenced by the formulation. Larvae exposed to plants treated with conidia formulated in aqueous Tween, Shellsol T, or sunflower oil/Shellsol T resulted in 55, 82.5 and 72.5%, mortality, respectively. The mortality for these respective formulations was reduced by 42, 57 and 51% if the plants were exposed for 1 h to simulated rain. Laboratory and field studies showed that more inoculum collected beneath plants sprayed with conidia formulated in Shellsol T or aqueous Tween than in the more viscous sunflower/Shellsol T mixture. Mortality studies on leaves taken from field plots suggested that conidia on leaf surfaces could be replenished by repeated application. The number of conidia isolated from field plots was greater where inoculum was applied bi-weekly than once weekly.

Scleroderris canker of conifer is caused by Gremmeniella abietina var. abietina, which comprises several taxa, including races, varieties, and biotypes. The European race of G. abietina var. abietina was introduced into North America early in the century, most likely on asymptomatic infected pine seedlings, and is currently widespread in eastern North America. In order to detect latent infections and differentiate the North American and European races of the fungus, we developed oligonucleotide primers to amplify by PCR portions of the ITS of the ribosomal DNA of G. abietina var. abietina. The 417 bp amplified DNA fragment comprises two Msp I restriction sites in the NA race but only one in the EU race. DNA extractions directly from infected asymptomatic needles, or from single fruiting bodies, followed by PCR amplification and Msp I digestion allowed the detection and race identification of both races of G. abietina var. abietina from seedlings and branches of Pinus resinosa and P. banksiana. A nested PCR assay was sensitive enough to detect the equivalent of a single infected seedling in a bulk sample of 1000 healthy seedlings. Validation tests were conducted by comparing PCR and isolation assays with 104 fascicles. All samples for which the fungus was isolated yielded a positive PCR assay and there was no false negative, i.e. samples for which the fungus was isolated but not detected by PCR. Among the samples from which the fungus was not isolated, most yielded a negative PCR assay (71%), but a proportion (29%) yielded positive PCR assays. In several of those cases, aggressive contaminants had apparently overgrown the pathogen. The method described here can lead to the detection and race identification of the NA and EU races of G. abietina var. abietina directly from infected tissues without the need to culture the fungus and should find applications in nursery inspection and quarantine.

This new feature in Mycological Research is introduced, and invitations to contribute to it are made. It introduces the contents of the issue, draws attention to exciting research published elsewhere, and will also include comments on papers previously published in Mycological Research.

This month Mycological Research includes papers which report a 20 million year old resinicolous ascomycete, contribute to the molecular biology and phylogeny of Antrodiella, Serpula, Trichoderma, Typhula, and Uncinula, marine ascomycetes, and conidial smut fungi. Magnesium tolerance, phosphatase activity in endomycorrhizal fungi, and Tolypocladium as an entomopathogen are also featured. One new genus and five species new to science are described. An obituary for G. C. Ainsworth is provided.

Recent research is reported on here which demonstrates that pyrenomycete fungi evolved earlier than previously documented, studies on tropical palms which suggest there may be even more fungi than we suspected, and a group of hitherto undetected ascomycetes with naked asci living inside discomycete apothecia has been discovered. Proposals to streamline aspects of botanical (including mycological) nomenclature have been thwarted at the XVI International Botanical Congress in St Louis.

PCR amplification revealed length polymorphism of the 3′ region of the SSU rDNA gene among special forms of Fusarium solani. These length polymorphisms were found within each of F. solani f. sp. phaseoli, f. sp. batatas and f. sp. piperis. Nucleotide sequence analysis in this region detected intron-like sequences ranging in size from 408 to 439 bp and one 12 bp. The six 408 to 439 bp intron-like sequences were classified into types I-1 and I-2. The sequence similarity was high within I-1 or I-2 type sequences (84.8% and 81.1 to 92.8%, respectively) compared to that between I-1 and I-2 type sequences (45.7 to 48.5%). Both I-1 and I-2 type sequences had a specific insertion point in the SSU rDNA 3′ region. I-1 type sequences had the characteristics of group I introns: (1) a U at the 5′ splice site of the exon, (2) a G at the 3′ splice site of the intron, and (3) they contained the conserved sequence elements P, Q, R, and S. I-2 type sequences had characteristics: (1) and (2), but they did not have any characteristic (3). The 12 bp intron-like sequence was identical to the part of the 5′ end of I-2 type sequences, and its insertion point was the end of I-2 type sequences. The presence or absence of these intron-like sequences caused the length polymorphism of the SSU rDNA 3′ region of F. solani.

This month Mycological Research News features group sex in New England, the recovery of viable fungal spores from 140 000 year old glaciers, and the role of ericoid mycorrhizas in conveying arsenate resistance to their plant partners.

The lead paper in this issue is an historical and morphological critique of the supposed differences of gasteromycetes from other basidiomycetes. Amongst the other 17 papers in this issue are molecular studies on Ganoderma in Australia, Melampsora on Salix, Phaeosphaeria sexual progeny, endomycorrhizal Pisolithus isolates, and cultured and in situ wood decomposing fungi. Complementary isozyme studies on Ganoderma in Australia are also presented. Adhesion and infection in Pestalotiopsis conidia has been examined, the yeasts associated with ant mounds in Texas analyzed, dual infections of grasses with different Neotyphodium endophytes studied experimentally, the detection of Botrytis cinerea by monoclonal antibodies raised by different immunogens assessed, the action of Verticillium fungicola on Agaricus bisporus hyphae examined, and the efficacy of Fusarium tumidum isolates with biocontrol potential against gorse and broom compared. A long-fruiting population of Morchella conica is documented, and numerous isolates of nematophagous fungi have been found in sheep faeces in Brazil.

The following new scientific names are introduced: Hebeloma radicosoides, Ramularia byrsonimatis, and Rhizosphaera pseudotsugae spp. nov.; and Pseudocercospora byrsonimatis (syn. Cercospora byrsonimatis) comb. nov.

This month Mycological Research News features work on chromosome translocations in six closely related Saccharomyces species, and analyses of the largest rDNA data sets of fungi yet published which call into question some proposed phylogenies and natural groupings.

Amongst the 16 papers in this issue are molecular studies exploring the diversity of soil fungi, rDNA and taxonomy of Ganoderma, RAPD analyses of Armillaria mellea populations, relationships of Phytophthora species, variation in P. cactorum, dsRNA viruses in Metarhizium anisopliae isolates, the genetic structure of Cryphonectria parasitica populations, and the array of Trichoderma isolates from Russia, Siberia and Himalaya.

The effects of mycorrhizal and non-mycorrhizal root exudates on the sporulation of Phytophthora fragariae are reported, and the cytology and ultrastructure of Fusarium culmorum and Mycosphaerella graminicola on wheat are documented.

The fruiting inducing factor from Phellinus contiguus has been partially characterized, and the resistance of Acer pseudoplatanus wood to Armillaria mellea degradation is explored.

The distribution of fungi on fallen Pinus sylvestris needles is examined along altitudinal transects, and a remarkable diversity of fungi on Picea abies documented.

Craspedodidymum nigroseptatum sp. nov. is described and a key to the species provided.

Conidia of the entomopathogenic Metarhizium flavoviride were harvested 8, 10, 12 or 15 d after inoculation at 25 °C and then (as conidiated rice) dried rapidly (10–12% r.h. and 17–20° for 17 h to about 15–22% moisture content) or slowly (50–60% r.h. and 27° for 5 d to about 27–32% moisture content initially). The subsequent survival of these conidia in air-dry storage at 50° with 8·1% moisture content was then assessed. Conidia longevity (assessed by the duration of storage until conidia viability was reduced to 50%, p50) was maximal when conidia were harvested 10 d after inoculation, and was much greater following slow rather than rapid drying. The substantial beneficial effect of slow desiccation to subsequent conidia survival is consistent with that detected in other propagules in anhydrous biology, and is also of considerable practical utility for the biological control of insects by entomopathogenic fungi.

A phylogenetic analysis based on internal transcribed spacer regions of the nuclear ribosomal RNA region (ITS) sequences has been undertaken for species in the genus Schizopora. Four known species were studied, viz. S. radula, S. paradoxa, S. flavipora, S. nothofagi, and a hitherto undescribed species from Taiwan. Allopatric differentiation was apparent in S. radula, for which several geographically representive samples were available. Among these, ITS sequence data obtained from S. radula isolates from British Columbia and Australasia were identical. All previously recognised Schizopora species were well separated from each other with respect to their ITS sequences. Mating compatibility tests also showed complete reproductive separation between species, but intercompatibility between cultures from the same species, irrespective of geographical origin. Overall, the morphology of basidiomes of S. radula from New Zealand differs only in minor respects from those of European and Argentinean origin, but shows a higher degree of variability than described for European specimens.

Chaenothecopsis bitterfeldensis sp. nov. is described and illustrated from Bitterfeld amber dating back to at least 20 million years ago. There has been no previous report of the sporing perfect stage of any Ascomycota in amber. The fungus also represents the first fossil record of resinicolous fungi and of the Mycocaliciaceae. The fossilised specimen contains over 20 fruiting bodies arising from an extensive mycelium. There are also hundreds of detached ascospores, some of which had germinated before the resin was transformed into amber. The taxonomy and palaeontology of the fossil fungus is discussed and stages in its preservation are described. Also some general aspects in the biology of resinicolous Mycocaliciaceae are reviewed. The striking similarity of C. bitterfeldensis to some extant species from East Asia suggests that the present distribution of these fungi is a relict of an ancient Laurasian range.

This paper reports a study aimed at gaining new information on the molecular composition of fruitbodies of Tuber spp. The presence of proteins homologous to TBF-1, which is highly specific for the fruitbody-phase of Tuber borchii, has been investigated in other white truffles. SDS-PAGE analyses revealed that only Tuber dryophilum fruitbodies possess a similar protein. This protein was purified by HPLC and partially sequenced, confirming a high degree of homology with TBF-1. Several PCR analyses of the genomic DNA, were performed to evaluate whether the absence of proteins homologous to TBF-1 in other white truffle species was a result of the absence of the coding genes. T. dryophilum gave an amplification product corresponding to the entire gene (tdf-1), but no products were obtained from the other species. Tdf-1 was sequenced and its organisation studied since it is one of the first genes isolated from a Tuber species. The deduced amino acid sequence was compared to that of TBF-1, to evaluate the presence of conserved regions, in an attempt to gain new information about their role in fruitbody formation.