Mycological Research is changing for the new millennium. The journal is the major outlet for original mycological research world-wide, reaching the desks of more mycologists than any other in the discipline. Papers in all fields of pure and applied mycology are published, including biochemistry, biocontrol, biodeterioration, biodiversity, biotechnology, ecology, evolution, food spoilage, industrial mycology, genetics, lichens, molecular biology, medical and veterinary mycology, mycorrhizas, mycotoxins, ontogeny, physiology, plant pathology, systematics, ultrastructure, and yeasts. Papers of any length will be considered, as will collections from symposia or workshops (subject to the same review process as other papers). Review articles, which have proved so popular in the past, are encouraged. The journal is available on-line as well as in hard-copy (http://www.journals.cup.org). Advance contents lists are available through the British Mycological Society's home-page(http://www.ulst.ac.uk/faculty/science/bms).

The retirement of David Moore from the position of Executive Editor of Mycological Research brings to a conclusion a period during which the journal has consolidated its role as the leading international publication in fungal biology, serving the needs of professional mycologists and a host of other research workers in many related fields.

Dr Moore was first appointed as an editor of the then Transactions of the British Mycological Society in January 1985 at a time when its Editorial Board consisted of about fourteen British members.

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.

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.

Several species of Typhula cause diseases of cereals and grasses at low temperatures. Taxonomic separation of T. phacorrhiza, T. incarnata and T. ishikariensis was investigated using RAPD, ITS-RFLP and nucleotide sequencing of the ITS region. Using 10 RAPD primers on genomic DNA or eight restriction enzymes on PCR-amplified ITS regions, banding patterns were generated for each of 19 isolates from five species or varieties. Polymorphisms were found between species and varieties, with fewer among isolates within species or varieties. RAPD analysis suggested that T. ishikariensis var. idahoensis may be distinct from the other varieties (var. ishikariensis and var. canadensis), although this was not supported by ITS-RFLP. To confirm relationships, ITS nucleotides were obtained from single isolates of each of the five Typhula taxa, and sequence alignments were subjected to distance and parsimony analysis. Although there were differences in branching between dendrograms derived from sequencing vs. RAPD or ITS-RFLP, sequence data supported the distinction of the three main Typhula species, with the T. ishikariensis varieties grouping together and showing differences at an infraspecific level. ITS sequence data also indicated the closer taxonomic affinity of Typhula species to the agaricoid Tricholoma sejunctum compared to the clavarioid Thelephora terrestris.

Ribosomal DNA sequences were assessed for their usefulness in distinguishing among Trichoderma isolates and for their robustness in resolving their phylogenetic relationships. DNA sequences from the D2 region of the 28S rRNA gene were determined for 50 Trichoderma isolates representing seven species. Eight distinct sequence types existed, and were mostly consistent with groupings based on morphology. Sequence variability within the D2 region alone was not sufficient to provide a reliable phylogeny. Sequences from the ITS1, 5.8S and ITS2 regions were subsequently determined for 18 of the isolates. Eight distinct ITS sequence types were detected among these 18 isolates. The ITS sequence types were generally consistent with morphology, ITS1 sequence data supported the identification of the Th3 T. harzianum group of Muthumeenakshi et al. (1994) as T. atroviride. The data also confirmed that the biocontrol strains of this study were different from those causing disease problems in the mushroom industry in Europe and North America. Results from the phylogenetic analysis stress the importance of testing the robustness of data used to predict phylogenies. Two ITS sequence data sets for the same group of isolates produced significantly different phylogenies. Congruence analysis detected that T. inhamatum (GJS90-90) was corrupting tree topologies and ‘first order pruning’ was performed by removing its sequence from the two ITS data sets. Subsequent differences in the topologies of pruned ITS1 and ITS2 trees were attributed to a lack of phylogenetic information in the ITS2 sequence region. Although ITS sequences successfully differentiated among morphologically distinct isolates within Trichoderma, it did not provide a sufficient phylogenetic signal to resolve all of their relationships.

Cladistic analysis was performed on partial sequences from the nuclear-encoded small subunit ribosomal DNA. Four Halosarpheia spp., Lignincola laevis and Nais inornata were examined to determine the placement of these genera within the unitunicate ascomycetes. Two equally most parsimonious cladograms resulted from the analysis of the data. In a strict consensus of the two cladograms the taxa sampled did not form a monophyletic group, and Halosarpheia was shown to be polyphyletic. The marine Halosphaeriales formed a subclade with taxa from the Microascales. Data indicate that L. laevis and N. inornata may be congeneric, but other species of both genera require further study.

Clonal isolates of Uncinula necator, the grapevine powdery mildew pathogen, were characterized by mating type, RFLP and PCR analyses. Five random genomic clones, consisting of three multi-copy and two low-copy sequences, were used as probes for hybridization. The oligonucleotides (CAC)5, (GACA)4, the core sequence of the M-13 minisatellite region and the consensus region from a plant intron splice junction (R1), were used as primers in PCR reactions. The DNA probes detected high levels of genetic diversity in U. necator, identifying 34 unique haplotypes among the 81 isolates analysed, with a Shannon diversity index of D′=0·85. In comparison, 15 haplotypes were resolved in PCR reactions with the four primers, resulting in a diversity index of D′=0·59. The overall diversity within the collection, by combining RFLP and PCR data, was D′=0·88, distinguishing 37 haplotypes. The RFLP analysis provided greater discrimination of individual haplotypes than did PCR. Phenetic analysis of the RFLP and PCR data separately and in combination revealed two broad phenetic groups. The average overall similarity between the two groups was 40%. Mating of isolates from the two phenetic groups resulted in viable ascospores. The combination of RFLP, PCR and mating techniques was effective in determining levels of diversity and provided insight into the genetic relatedness of U. necator isolates.

In order to integrate ustilaginomycetous anamorphs into the general phylogenetic system of Ustilaginomycetes, partial nuclear large subunit ribosomal DNA sequences of 56 teleomorphic and 19 anamorphic species of the Ustilaginomycetes were analysed. Maximum parsimony and neighbour joining confirm the new suprageneric system of Ustilaginomycetes and indicate that (i) the species of Pseudozyma represent anamorphs of Ustilaginales parasitizing grasses, (ii) Pseudozyma prolifica, the type of Pseudozyma, is very closely related to Ustilago maydis, (iii) Pseudozyma tsukubaënsis is probably synonymous with Ustilago spermophora, (iv) the species of Malassezia represent a group of its own within the Exobasidiomycetidae, (v) Tilletiopsis cremea, T. lilacina and T. washingtonensis belong to the Entylomatales and (vi) T. flava, T. fulvescens and T. minor are members of the Georgefischeriales. Like all Tilletiopsis species tested, T. albescens and T. pallescens are members of the Exobasidiomycetidae, but they cannot be ascribed to any of the known orders of this subclass. The description of the Malasseziales is emended.

Nine isolates of Peronosclerospora sorghi from maize, sorghum and wild sorghum were sampled from Zimbabwe, Zambia, Rwanda, Mozambique and Kenya. They were compared for variation in conidium and conidiophore morphology, temperature requirements for sporulation, germination and germ-tube growth and for pathogenicity on different sorghum and maize cultivars. Although there were significant differences in isolate morphology, all conformed to the known range for P. sorghi. Mean conidial length×width ranged from 21–23 μm×16·9–19·2 μm, and mean conidiophore length (basal cell-branching) ranged from 116·3–135·6 μm. All isolates sporulated in the range 14–26 °C (optimal at 16–23°), although one isolate from maize from Umbeluzi in Mozambique had a broader optimal range for sporulation (12–25°). Conidia of all isolates germinated between 10° and 34°. Germ-tube response to temperature was similar for all isolates (10–34°). The isolates varied in their pathogenicity towards sorghum cultivars, with an isolate from Rwanda being pathogenic to more sorghum differentials than any other. Cluster analysis of isolates based on host reaction indicated five groups at the 85% similarity level. The existence of pathogenic variability has ramifications for the breeding of sorghum for resistance to downy mildew in Africa.

The ITS of the nuclear ribosomal DNA of Serpula lacrymans and S. himantioides was amplified by PCR to evaluate this DNA region as a diagnostic tool. Sequencing of the amplified ITS region revealed a size of the complete ITS of 654 bp for S. lacrymans and 650 bp for S. himantioides. The base sequence difference between the two fungi was used to design species-specific oligonucleotide PCR primers for both species. With laboratory and field samples, each primer selectively detected its target organism. No cross reaction occurred with other fungi causing rot of indoor wood.

An isolate of Coniothyrium minitans did not sporulate on media to which 0·05 mM magnesium was added when κ-carrageenan was used to solidify the medium. Normal conidiation was observed when a technical grade agar or agar-agar was used as the gelling agent. The κ-carrageenan and agars used in this study contained significant amounts of Mg. In the agar media all the Mg present was available to the fungus. By contrast, in the κ-carrageenan gel a large portion of the Mg was bound by the gel and not available. Sporulation of C. minitans was only observed on media containing [ges ]0·17 mM of unbound Mg. The possible role of Mg in the initiation of conidium formation by C. minitans is discussed.

Two unusual species of Acremonium sect. Acremonium, A. borodinense sp. nov. and A. cavaraeanum, are described and illustrated. They were isolated in Japan from rhizosphere soil of sugarcane and an outer wall of a wooden house respectively. A. borodinense is characterized by forming two kinds of conidia, ellipsoidal rough-walled and cylindrical smooth-walled. Of A. cavaraeanum a second isolate has become available; it forms long chains of fusiform conidia, has a luteous reverse and exudes a livid-red pigment into the medium.

Extraradical hyphae of Glomus intraradices or G. claroideum were extracted from root free sand of two-compartment pot cultures and used to determine fungal phosphatase activity [p-nitrophenyl phosphate (p-NPP) hydrolysis]. Enzyme activity was assayed with respect to pH, temperature and different fractions of the hyphae (external soluble, wall-bound and internal phosphatases). The results showed an overall maximum enzyme activity at pH 5·2–5·6 for both fungi, with a possible secondary maximum at pH [ges ]8·8 for G. claroideum. Of the two fungi tested, G. intraradices had the highest external phosphatase activity in two experiments and the same activity in one experiment, reaching 184 μmol p-NPP hydrolysed mg−1D.W. h−1. Phosphatase activity at pH 5·2 decreased sharply with temperature, with 4·5 and 10·5% of the enzyme activity remaining at 5 °C relative to that at 37° for G. intraradices and G. claroideum, respectively. Separation of the phosphatase activity into external soluble, wall-bound and internal fractions revealed that up to 70% of the measured activity was associated with the hyphal wall, and the rest with internal structures. Exuded phosphatases were not found in measurable amounts. The implications of these results on possible hyphal utilization of organic P in soil are discussed.

At one sampling site an entomopathogenic fungus, tentatively identified as Tolypocladium cylindrosporum, was found to severely reduce populations of hibernating turnip moth larvae (Agrotis segetum) in consecutive winters, while it was never recorded from other collection sites. It produced cylindrical conidia (5·5×2 μm) and smaller, ellipsoidal conidia (3·8×2·8 μm) in slimy heads from flask-shaped phialides with thin necks, which occasionally were bent. Phialides were scarce and never occurred in true verticils. Colonies were pale yellow, cottony on artificial medium, with a characteristic mouldy smell. The infectivity of the fungus was tested in a semi-field trial, where suspensions of conidia were applied to hibernating turnip moth larvae in plastic buckets. The experiment also included buckets with larvae and/or soil from the infested site in order to study the natural fungal-induced mortality. The experiment was started in mid-October and buckets were collected four times from January until May. The fungus had caused high mortality by January, when almost 70% of the treated larvae were infected and by March more than 94% of the larvae had been killed. For larvae from the naturally infested site the prevalence was 21% in mid-October and by March it had reached 93%. The ability of the fungus to infect insects at low temperatures may be related to a relatively low optimum temperature for growth of 21 °C, which is lower than for the majority of entomopathogenic hyphomycetes. Host range studies with 10 insect species indicated that the fungus is probably specific to hibernating cutworms.

The ITS region of ribosomal DNA was sequenced for 30 isolates or sporocarps (including five type specimens) representing ten European taxa of Antrodiella. Phylogeny was inferred from the sequences by parsimony with Steccherinum ochraceum as an outgroup. The phylogram is discussed in relation to morphological and ecological characteristics of the species. On the basis of both morphological and molecular data Antrodiella pallasii sp. nov. is described. The study did not support the separation of A. beschidica and A. farinacea from A. semisupina. A. faginea is reported from Fennoscandia.

Two species of Haptoglossa isolated from nematodes from cow manure from N.E. England are described. H. erumpens sp. nov., infecting Bunonema nematodes, is aplanosporic, the cysts being released after rupture of the nematode cuticle in the absence of an evacuation tube. H. dickii sp. nov. is zoosporic, infecting several species of rhabditid nematodes. Aplanospores and zoospore cysts germinated to produce secondary spores (gun cells) with which to infect further nematode hosts. Some key ultrastructural features in both species have been included.

Bulbocatenospora complanata gen. et sp. nov. is described and illustrated. The fungus is characterized by the production of inconspicuous, brown conidiophores, usually reduced to the conidiogenous cells, which are monotretic, ventricose, dark brown, with a well-defined pore. The conidia are muriform, broadly ovoid to irregular, complanate, brown, forming short, acropetal chains. The fungus was found on rotten leaves of Bactris setulosa in an undisturbed rainforest in Venezuela. Comparisons are made with some morphologically similar genera, Piricauda, Chuppia and Janetia.

Geoffrey Clough Ainsworth was a mycological scholar of distinction, with an unparalleled knowledge of the bibliography and history of the subject. An indefatigable worker and campaigner for all aspects of the mycological cause, his contributions to the documentation and internationalisation of mycology have had enormous and on-going influences.

Geoffrey was born in Birmingham on 9 October 1905, the only son of the Rev. Percy Clough Ainsworth. Educated at Ipswich Grammar School and Kingswood School in Bath, he proceeded to the then University College Nottingham, obtaining first class honours in botany in 1930. En route in 1929, he obtained a certificate in pharmacy and was awarded the Pharmaceutical Society's Silver Medal and Harrison Memorial Prize. He was then lured into plant pathology, first working as an assistant at Rothamsted Experimental Station from 1930–31, and then as a virologist at the Experimental and Research Station in Cheshunt, Hertfordshire, from 1931–39. The period at Cheshunt was an enormously productive one for Geoffrey. He took a particular interest in virus diseases of horticultural plants, on which he started to publish profusely, including the first of many contributions to Nature in 1936. At the same time he obtained a PhD from the University of London in 1934, and compiled his first book: The Plant Diseases of Great Britain (1937) – a bibliographic account of the different diseases caused by bacteria, fungi and viruses arranged by host.