The colonization of land by plants appears to have coincided with the appearance of mycorrhiza-like fungi. Over evolutionary time, fungi have maintained their prominent role in the formation of mycorrhizal associations. In addition, however, they have been able to occupy other terrestrial niches of which the decomposition of recalcitrant organic matter is perhaps the most remarkable. This implies that, in contrast to that of aquatic organic matter decomposition, bacteria have not been able to monopolize decomposition processes in terrestrial ecosystems. The emergence of fungi in terrestrial ecosystems must have had a strong impact on the evolution of terrestrial bacteria. On the one hand, potential decomposition niches, e.g. lignin degradation, have been lost for bacteria, whereas on the other hand the presence of fungi has itself created new bacterial niches. Confrontation between bacteria and fungi is ongoing, and from studying contemporary interactions, we can learn about the impact that fungi presently have, and have had in the past, on the ecology and evolution of terrestrial bacteria. In the first part of this review, the focus is on niche differentiation between soil bacteria and fungi involved in the decomposition of plant-derived organic matter. Bacteria and fungi are seen to compete for simple plant-derived substrates and have developed antagonistic strategies. For more recalcitrant organic substrates, e.g. cellulose and lignin, both competitive and mutualistic strategies appear to have evolved. In the second part of the review, bacterial niches with respect to the utilization of fungal-derived substrates are considered. Here, several lines of development can be recognized, ranging from mutualistic exudate-consuming bacteria that are associated with fungal surfaces to endosymbiotic and mycophagous bacteria. In some cases, there are indications of fungal specific selection in fungus-associated bacteria, and possible mechanisms for such selection are discussed.

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We present a 6-gene, 420-species maximum-likelihood phylogeny of Ascomycota, the largest phylum of Fungi. This analysis is the most taxonomically complete to date with species sampled from all 15 currently circumscribed classes. A number of superclass-level nodes that have previously evaded resolution and were unnamed in classifications of the Fungi are resolved for the first time. Based on the 6-gene phylogeny we conducted a phylogenetic informativeness analysis of all 6 genes and a series of ancestral character state reconstructions that focused on morphology of sporocarps, ascus dehiscence, and evolution of nutritional modes and ecologies. A gene-by-gene assessment of phylogenetic informativeness yielded higher levels of informativeness for protein genes (RPB1, RPB2, and TEF1) as compared with the ribosomal genes, which have been the standard bearer in fungal systematics. Our reconstruction of sporocarp characters is consistent with 2 origins for multicellular sexual reproductive structures in Ascomycota, once in the common ancestor of Pezizomycotina and once in the common ancestor of Neolectomycetes. This first report of dual origins of ascomycete sporocarps highlights the complicated nature of assessing homology of morphological traits across Fungi. Furthermore, ancestral reconstruction supports an open sporocarp with an exposed hymenium (apothecium) as the primitive morphology for Pezizomycotina with multiple derivations of the partially (perithecia) or completely enclosed (cleistothecia) sporocarps. Ascus dehiscence is most informative at the class level within Pezizomycotina with most superclass nodes reconstructed equivocally. Character-state reconstructions support a terrestrial, saprobic ecology as ancestral. In contrast to previous studies, these analyses support multiple origins of lichenization events with the loss of lichenization as less frequent and limited to terminal, closely related species.

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With the recent changes concerning pleomorphic fungi in the new International Code of Nomenclature for algae, fungi, and plants (ICN), it is necessary to propose the acceptance or protection of sexual morph-typified or asexual morph-typified generic names that do not have priority, or to propose the rejection or suppression1 of competing names. In addition, sexual morph-typified generic names, where widely used, must be proposed for rejection or suppression in favour of asexual morph-typified names that have priority, or the latter must be proposed for conservation or protection. Some pragmatic criteria used for deciding the acceptance or rejection of generic names include: the number of name changes required when one generic name is used over another, the clarity of the generic concept, their relative frequencies of use in the scientific literature, and a vote of interested mycologists. Here, twelve widely used generic names in three families of Hypocreales are proposed for acceptance, either by conservation or protection, despite their lack of priority of publication, or because they are widely used asexual morph-typified names. Each pair of generic names is evaluated, with a recommendation as to the generic name to be used, and safeguarded, either through conservation or protection. Four generic names typified by a species with a sexual morph as type that are younger than competing generic names typified by a species with an asexual morph type, are proposed for use. Eight older generic names typified by species with an asexual morph as type are proposed for use over younger competing generic names typified by a species with a sexual morph as type. Within Bionectriaceae, Clonostachys is recommended over Bionectria; in Hypocreaceae, Hypomyces is recommended over Cladobotryum, Sphaerostilbella over Gliocladium, and Trichoderma over Hypocrea; and in Nectriaceae, Actinostilbe is recommended over Lanatonectria, Cylindrocladiella over Nectricladiella, Fusarium over Gibberella, Gliocephalotrichum over Leuconectria, Gliocladiopsis over Glionectria, Nalanthamala over Rubrinectria, Nectria over Tubercularia, and Neonectria over Cylindrocarpon.

The number of individuals diagnosed with diabetes mellitus is increasing. The diabetic may present with complications involving all systems of the body. While onychomycosis is often observed in diabetics, there have been no large studies on the prevalence of the condition in this patient group. We examined the prevalence of onychomycosis in diabetics attending diabetes and dermatology clinics in London, Ontario, Canada and Boston, MA, U.S.A. Diabetic subjects seen in dermatology offices were for unrelated dermatoses; those referred specifically for the management of onychomycosis were excluded from the sample. A total of 550 diabetic subjects was evaluated (283 males and 267 females), age 56.1 +/- 0.7 years (mean +/- SEM). Patients with type I diabetes constituted 34% of the sample. The racial origin was: 531 Caucasians, 17 Asians, one African-American and one American-Indian. Abnormal-appearing nails and mycological evidence of onychomycosis (mostly due to dermatophytes) were present in 253 (46%) and 144 (26%), respectively, of 550 subjects. The development of onychomycosis was significantly correlated with age (P < 0.0001) and male gender (P < 0.0001). Males were 2.99 times more likely to have onychomycosis compared with females (95% confidence interval, CI 1.94-4 61). After controlling for age and sex, the risk odds ratio for diabetic subjects to have toenail onychomycosis was 2.77 times compared with normal individuals (95% CI 2.15-3.57). After controlling for age and sex, a stepwise logistic regression demonstrated that significant predictors for onychomycosis included a family history of onychomycosis (P = 0.0001), concurrent intake of immunosuppressive therapy (P = 0.035) and peripheral vascular disease (P = 0.023). Toenail onychomycosis was present in 26% of the sample and is projected to affect approximately one-third of subjects with diabetes. Predisposing factors include increasing age, male gender, family history of onychomycosis, concurrent intake of immunosuppressive agents and peripheral vascular disease.

The genus Togninia (Diaporthales, Togniniaceae) is here monographed along with its Phaeoacremonium (Pm.) anamorphs. Ten species of Togninia and 22 species of Phaeoacremonium are treated. Several new species of Togninia (T.) are described, namely T. argentinensis (anamorph Pm. argentinense), T. austroafricana (anamorph Pm. austroafricanum), T. krajdenii, T. parasitica, T. rubrigena and T. viticola. New species of Phaeoacremonium include Pm. novae-zealandiae (teleomorph T. novae-zealandiae), Pm. iranianum, Pm. sphinctrophorum and Pm. theobromatis. Species can be identified based on their cultural and morphological characters, supported by DNA data derived from partial sequences of the actin and β-tubulin genes. Phylogenies of the SSU and LSU rRNA genes were used to determine whether Togninia has more affinity with the Calosphaeriales or the Diaporthales. The results confirmed that Togninia had a higher affinity to the Diaporthales than the Calosphaeriales. Examination of type specimens revealed that T. cornicola, T. vasculosa, T. rhododendri, T. minima var. timidula and T. villosa, were not members of Togninia. The new combinations Calosphaeria cornicola, Calosphaeria rhododendri, Calosphaeria transversa, Calosphaeria tumidula, Calosphaeria vasculosa and Jattaea villosa are proposed.Species of Phaeoacremonium are known vascular plant pathogens causing wilting and dieback of woody plants. The most prominent diseases in which they are involved are Petri disease and esca, which occur on grapevines and are caused by a complex of fungi, often including multiple species of Phaeoacremonium. Various Phaeoacremonium species are opportunistic fungi on humans and cause phaeohyphomycosis. The correct and rapid identification of Phaeoacremonium species is important to facilitate the understanding of their involvement in plant as well as human disease. A rapid identification method was developed for the 22 species of Phaeacremonium. It involved the use of 23 species-specific primers, including 20 primers targeting the β-tubulin gene and three targeting the actin gene. These primers can be used in 14 multiplex reactions. Additionally, a multiple-entry electronic key based on morphological, cultural and β-tubulin sequence data was developed to facilitate phenotypic and sequence-based species identification of the different Phaeoacremonium species. Separate dichotomous keys are provided for the identification of the Togninia and Phaeoacremonium species. Keys for the identification of Phaeoacremonium-like fungi and the genera related to Togninia are also provided. The mating strategy of several Togninia species was investigated with ascospores obtained from fertile perithecia produced in vitro. Togninia argentinensis and T. novae-zealandiae have homothallic mating systems, whereas T. austroafricana, T. krajdenii, T. minima, T. parasitica, T. rubrigena and T. viticola were heterothallic

Because less than one-third of clinically relevant fusaria can be accurately identified to species level using phenotypic data (i.e., morphological species recognition), we constructed a three-locus DNA sequence database to facilitate molecular identification of the 69 Fusarium species associated with human or animal mycoses encountered in clinical microbiology laboratories. The database comprises partial sequences from three nuclear genes: translation elongation factor 1␣ (EF-1␣), the largest subunit of RNA polymerase (RPB1), and the second largest subunit of RNA polymerase (RPB2). These three gene fragments can be amplified by PCR and sequenced using primers that are conserved across the phylogenetic breadth of Fusarium. Phylogenetic analyses of the combined data set reveal that, with the exception of two monotypic lineages, all clinically relevant fusaria are nested in one of eight variously sized and strongly supported species complexes. The monophyletic lineages have been named informally to facilitate communication of an isolate's clade membership and genetic diversity. To identify isolates to the species included within the database, partial DNA sequence data from one or more of the three genes can be used as a BLAST query against the database which is Web accessible at FUSARIUM-ID (http://isolate.fusariumdb.org) and the Centraalbureau voor Schimmelcultures (CBS-KNAW) Fungal Biodiversity Center (http://www.cbs.knaw.nl/fusarium). Alternatively, isolates can be identified via phylogenetic analysis by adding sequences of unknowns to the DNA sequence alignment, which can be downloaded from the two aforementioned websites. The utility of this database should increase significantly as members of the clinical microbiology community deposit in internationally accessible culture collections (e.g., CBS-KNAW or the Fusarium Research Center) cultures of novel mycosis-associated fusaria, along with associated, corrected sequence chromatograms and data, so that the sequence results can be verified and isolates are made available for future study.