This issue of Mycological Research News features: In this issue; A century of rhizosphere research: fungal interactions with plant's hidden half; Two major changes in fungal nomenclature enacted in Vienna; UNITE: molecular identification of ectomycorrhizal fungi; and Sex and natural selection in yeast populations.

A review article details the 1244 descriptions of ectomycorrhizal fungi published since 1961, covering 814 morphotypes. Seven research papers are included in this part. The first addresses ectomycorrhizal mycobionts of Pisonia grandis in Australia.

Five focus on the characterization of ophiostomatoid fungi, combining morphological and molecular approaches: optional mitochondrial introns/insertions are analyzed in the Ophiostoma ulmi s. lat. complex, focussing on three genes (rns, rnl and cox1). A new Ophiostoma species is described from oak in Europe which has a Sporothrix anamorph. The Ceratocystis polonica complex is found to contain three species. A re-appraisal of the Leptographium lundbergii complex shows that also to comprise three species. The Leptographium species associated with the mountain pine beetle and a devastating lodgepole pine disease is described as new.

Finally, the manganese superoxide dismutases in Phytophthora nicotianae have been analysed and compared with those in other members of the genus.

The following new scientific names are introduced: Ceratocystis fujiensis, Hyalorhinocladiella pinicola, Leptographium longiclavatum, and Ophiostoma dentifidum spp. nov.

All available publications providing descriptions of ectomycorrhizas (ECM) were reviewed in order to build a database containing details on fungus forming the ECM, host tree, country where the material for description was collected, and habitat of the ECM. Other secondary data were also recorded. In all 1244 descriptions of ECM published since 1961 in 479 papers were reviewed. The number of different ECM morphotypes described was 814. Most ECM described were collected in Europe and North America. Gymnosperms were the most common tree associates, and boreal and temperate forests the most studied ecosystems. Fungal symbionts were mostly Basidiomycota, epigeous, and with mushroom-like morphology. The paper also addresses the gaps in ECM knowledge that mycorrhizologists should address in future studies.

The diversity of ectomycorrhizal mycobionts of Pisonia grandis (Nyctaginaceae) from coral cays in the Capricorn-Bunker group, Great Barrier Reef, Australia, was examined. Only two ectomycorrhiza morphotypes (brown and black) were identified in soil from seven cays and DNA from both morphotypes was subjected to ITS-RFLP and sequence analysis. The brown morphotype was present in soil from all cays but the black morphotype was only observed in soil from three cays. ITS-RFLP analysis showed that the brown and black morphotypes were formed by different fungal taxa, with the RFLP pattern for the black morphotype being consistent with that of the culture previously obtained from black ectomycorrhizal roots on Heron Island. Comparison with the GenBank database revealed that closest matches to both morphotypes were sequences for various Thelephoraceae (Basidiomycota), but the brown and black morphotypes had only 80% sequence similarity to each other. Neighbour-joining analysis of these sequences with sequences for other Thelephoraceae grouped the brown and black morphotypes in a well-supported clade with several Tomentella species, suggesting that both belong to this genus. The data are discussed in relation to ectomycorrhizal fungal diversity and the coral cay habitat.

Strains of Ophiostoma ulmi, O. novo-ulmi subsp. americana, O. novo-ulmi subsp. novo-ulmi and O. himal-ulmi were examined for optional introns/insertions within the following mitochondrial genes: small subunit RNA gene (rns), large ribosomal subunit gene (rnl) and the cytochrome oxidase subunit I gene (coxI). Insertions were noted in the rns and coxI genes in strains of O. ulmi, the less aggressive species, but absent in strains of the more aggressive O. novo-ulmi subsp. americana. Strains of all species examined had a group I intron present in the U11 region of the mitochondrial-rnl gene. In all but two strains of O. novo-ulmi subsp. americana, this rnl-U11 intron was about 1.5 kb in length whereas a 2.6 kb version of this element was present in all strains representing O. ulmi, O. novo-ulmi subsp. novo-ulmi, and Ophiostoma himal-ulmi. Irrespective of size, this intron based on RNA folds is a class IA1 group I intron and it encodes a putative ORF for the rps3 ribosomal protein. The size variation of the rnl-U11 intron was examined in detail for two strains of O. novo-ulmi subsp. americana and sequence data suggests the presence of a complex ORF within the 2.6 kb version of this intron; here a homing endonuclease-like gene has been inserted in frame and fused to the carboxyl-terminus of the putative rps3 coding region. The mitochondrial optional introns/insertions in combination with nuclear markers might be useful in distinguishing among the various species and subspecies of the O. ulmi s. lat. complex.

Previous phylogenetic studies based on ITS sequence data have shown that Ophiostoma species with Sporothrix anamorphs include several species complexes. Isolates from oak in Poland and Hungary, which have previously been referred to as O. stenoceras, as well as isolates morphologically similar to S. inflata formed the basis of this study. Identification was based on sequences for the ITS region of rDNA operon and partial β-tubulin gene. Analyses showed that isolates from Poland and Hungary reside in a well resolved clade, separate from those in the O. stenoceras-complex. The morphology of these isolates was compared with those of strains in the O. stenoceras complex and S. inflata. Morphological differences in teleomorph and anamorph structures were found between the isolates from Poland and Hungary and those in the O. stenoceras-complex. Growth characteristics and the presence of the teleomorph in culture could be used to separate this fungus from isolates in the S. inflata-complex. The fungus from Poland and Hungary is described here as O. dentifundum sp. nov. It is phylogenetically most closely related to isolates of S. inflata, which represent four well defined groups based on morphology and DNA sequence phylogeny.

Ceratocystis polonica and C. laricicola are two morphologically similar species that occur on conifers and reside in the Ceratocystis coerulescens species complex. They, however, represent two ecologically distinct entities. C. polonica causes blue stain on Norway spruce (Picea abies) and other spruce species (Picea spp.) in Eurasia and is associated with the bark beetles Ips typographus, I. typographus japonicus, I. amitinus and I. duplicatus. In contrast, C. laricicola lives in a symbiotic relationship with the bark beetles Ips cembrae and I. subelongatus that infest various larch species (Larix spp.). The objective of this study was to consider the phylogenetic relationships of C. polonica and C. laricicola and more specifically to determine the identity of Japanese isolates from both spruce and larch, based on sequences derived from the ITS regions of the rRNA operon, the β-tubulin gene and the HMG box of the MAT-2 gene. Isolates were also compared based on morphology and cultural characteristics. Comparisons of anamorph and teleomorph structures confirmed that C. polonica and C. laricicola are indistinguishable based on morphology. Both species had an optimal growth temperature of 25 °C. However, at temperatures between 31–33 °, C. polonica isolates grew slowly or not at all, while C. laricicola isolates grew more actively at these temperatures. Thus, a growth test at 32 ° can differentiate these species. Phylograms generated using parsimony for the three gene regions were strongly congruent. These showed three distinct clades supported by high bootstrap values. Two of the clades clearly separate C. laricicola from Europe and C. polonica, supporting the view that they represent two discrete taxa. A third clade included isolates obtained from galleries of Ips subelongatus on Larix kaempferi in Japan. This fungus clearly represents a discrete taxon that is closely related to, but distinct from C. laricicola, which is described here as C. fujiensis sp. nov.

The genus Leptographium was described in 1927 and currently includes 48 species, with L. lundbergii as the type species. In recent years, the taxonomic status of L. lundbergii has not been uniformly agreed upon and it has been the topic of considerable debate. The problem was compounded by the absence of a type specimen, and the species was epitypified at a later stage. Unfortunately, the whereabouts of the epitype is now unknown. In 1983, Wingfield & Marasas described L. truncatum, which is morphologically similar to L. lundbergii. Based on DNA comparisons and similarities in their morphology, this fungus was reduced to synonymy with L. lundbergii. The loss of the type specimen as well as variation in the morphology of strains identified as L. lundbergii prompted us to re-examine the taxonomic status of this species. A number of strains from various geographic areas were studied. These include a strain of L. lundbergii deposited at CBS by Melin in 1929 (CBS 352.29) as well as the ex-type strain of L. truncatum. The strains were compared based on morphology and comparison of multiple gene sequences. Three genes or genic regions, ITS2 and part of the 28S gene, partial β-tubulin and partial elongation factor 1-α were compared. Strains currently identified as L. lundbergii, represented a complex of species. Strains initially described as L. truncatum clustered separately from other L. lundbergii strains, could be distinguished morphologically and should be treated as a distinct taxon. L. lundbergii is provided with a new and expanded description based on a neotype designated for it. A third group was also identified as separate from the main L. lundbergii clade and had a distinct Hyalorhinocladiella-type anamorph, described here as H. pinicola sp. nov.

The mountain pine beetle, Dendroctonus ponderosae, and its fungal associates are devastating the lodgepole pine forests in British Columbia, Canada. During our fungal survey, an unknown Leptographium species has been consistently isolated from both D. ponderosae and infested lodgepole pine (Pinus contorta var. latifolia). This Leptographium species has similar morphology with the Leptographium anamorph of Ophiostoma clavigerum whose association with the D. ponderosae is well known. However, thorough morphological comparisons showed that this fungus is distinct from all the other Leptographium species described in the literature, and especially from O. clavigerum. Comparison of DNA sequences of multiple loci and the profiles by the PCR-RFLP marker also confirmed that this Leptographium species represents an undescribed taxon. Based on its distinct morphological, physiological characteristics and phylogenetic position, we describe it as L. longiclavatum sp. nov.

Three polypeptides with manganese superoxide dismutase (MnSOD) activity were found in mycelium, zoospores and germinated cysts of Phytophthora nicotianae. Their relative molecular weights in non-denaturing gels were approximately 34.5, 36 and 50 kDa. No evidence for the presence of either iron or copper/zinc SODs was detected at any of the developmental stages examined. The level of activity of the MnSOD polypeptides was similar in mycelia and spores. Degenerate PCR was used to amplify partial genes of two different MnSODs, designated PnMnSOD1 and PnMnSOD2, from P. nicotianae. Southern blot analysis indicated that there are two PnMnSOD1 genes in the P. nicotianae genome. Full length sequence was obtained for one of these genes, PnMnSOD1a, from a P. nicotianae bacterial artificial chromosome (BAC) library. RNA blots probed with PnMnSOD1 showed similar levels of expression in vegetative and sporulating hyphae, lower levels in germinated cysts and no detectable expression in zoospores. PnMnSOD1a had 96%, 97% and 99% amino acid identity with homologous genes from P. ramorum, P. infestans and P. sojae, respectively. The second gene cloned from P. nicotianae, PnMnSOD2, had only 38% amino acid identity with PnMnSOD1a and was homologous to MnSODs that possessed an N-terminal mitochondrial targeting sequence in Phytophthora species and other eukaryotes. Southern blots indicated that there is one copy of PnMnSOD2 in the P. nicotianae genome. PnMnSOD2 was expressed at similar levels in mycelia and germinated cysts but PnMnSOD2 transcripts were not detectable in zoospores.