Additions to the Mycosphaerella complex

Species in the present study were compared based on their morphology, growth characteristics in culture, and DNA sequences of the nuclear ribosomal RNA gene operon (including ITS1, ITS2, 5.8S nrDNA and the first 900 bp of the 28S nrDNA) for all species and partial actin and translation elongation factor 1-alpha gene sequences for Cladosporium species. New species of Mycosphaerella (Mycosphaerellaceae) introduced in this study include M. cerastiicola (on Cerastium semidecandrum, The Netherlands), and M. etlingerae (on Etlingera elatior, Hawaii). Mycosphaerella holualoana is newly reported on Hedychium coronarium (Hawaii). Epitypes are also designated for Hendersonia persooniae, the basionym of Camarosporula persooniae, and for Sphaerella agapanthi, the basionym of Teratosphaeria agapanthi comb. nov. (Teratosphaeriaceae) on Agapathus umbellatus from South Africa. The latter pathogen is also newly recorded from A. umbellatus in Europe (Portugal). Furthermore, two sexual species of Cladosporium (Davidiellaceae) are described, namely C. grevilleae (on Grevillea sp., Australia), and C. silenes (on Silene maritima, UK). Finally, the phylogenetic position of two genera are newly confirmed, namely Camarosporula (based on C. persooniae, teleomorph Anthracostroma persooniae), which is a leaf pathogen of Persoonia spp. in Australia, belongs to the Teratosphaeriaceae, and Sphaerulina (based on S. myriadea), which occurs on leaves of Fagaceae (Carpinus, Castanopsis, Fagus, Quercus), and belongs to the Mycosphaerellaceae

Septoria-like pathogens causing leaf and fruit spot of pistachio

Several species of Septoria are associated with leaf and fruit spot of pistachio (Pistacia vera), though their identity has always been confused, making identification problematic. The present study elucidates the taxonomy of the Septoria spp. associated with pistachio, and distinguishes four species associated with this host genus. Partial nucleotide sequence data for five gene loci, ITS, LSU, EF-1a, RPB2 and Btub were generated for a subset of isolates. Cylindroseptoria pistaciae, which is associated with leaf spots of Pistacia lentiscus in Spain, is characterised by pycnidial conidiomata that give rise to cylindrical, aseptate conidia. Two species of Septoria s. str. are also recognised on pistachio, S. pistaciarum, and S. pistaciae. The latter is part of the S. protearum species complex, and appears to be a wide host range pathogen occurring on hosts in several different plant families. Septoria pistacina, a major pathogen of pistachio in Turkey, is shown to belong to Pseudocercospora, and not Septoria as earlier suspected. Other than for its pycnidial conidiomata, it is a typical species of Pseudocercospora based on its smooth, pigmented conidiogenous cells and septate conidia. This phenomenon has also been observed in Pallidocercospora, and seriously questions the value of conidiomatal structure at generic level, which has traditionally been used to separate hyphomycetous from coelomycetous ascomycetes. Other than DNA barcodes to facilitate the molecular identification of these taxa occurring on pistachio, a key is also provided to distinguish species based on morphology

One fungus, which genes?: development and assessment of universal primers for potential secondary fungal DNA barcodes

The aim of this study was to assess potential candidate gene regions and corresponding universal primer pairs as secondary DNA barcodes for the fungal kingdom, additional to ITS rDNA as primary barcode. Amplification efficiencies of 14 (partially) universal primer pairs targeting eight genetic markers were tested across > 1 500 species (1 931 strains or specimens) and the outcomes of almost twenty thousand (19 577) polymerase chain reactions were evaluated. We tested several well-known primer pairs that amplify: i) sections of the nuclear ribosomal RNA gene large subunit (D1-D2 domains of 26/28S); ii) the complete internal transcribed spacer region (ITS1/2); iii) partial beta-tubulin II (TUB2); iv) gamma-actin (ACT); v) translation elongation factor 1-alpha (TEF1 alpha); and vi) the second largest subunit of RNA-polymerase II (partial RPB2, section 5-6). Their PCR efficiencies were compared with novel candidate primers corresponding to: i) the fungal-specific translation elongation factor 3 (TEF3); ii) a small ribosomal protein necessary for t-RNA docking; iii) the 60S L10 (L1) RP; iv) DNA topoisomerase I (TOPI); v) phosphoglycerate kinase (PGK); vi) hypothetical protein LNS2; and vii) alternative sections of TEF1 alpha. Results showed that several gene sections are accessible to universal primers (or primers universal for phyla) yielding a single PCR-product. Barcode gap and multi-dimensional scaling analyses revealed that some of the tested candidate markers have universal properties providing adequate infra- and inter-specific variation that make them attractive barcodes for species identification. Among these gene sections, a novel high fidelity primer pair for TEF1 alpha, already widely used as a phylogenetic marker in mycology, has potential as a supplementary DNA barcode with superior resolution to ITS. Both TOPI and PGK show promise for the Ascomycota, while TOPI and LNS2 are attractive for the Pucciniomycotina, for which universal primers for ribosomal subunits often fail

Phacidium and Ceuthospora (Phacidiaceae) are congeneric: taxonomic and nomenclatural implications

The morphologically diverse genus Ceuthospora has traditionally been linked to Phacidium sexual morphs via association, though molecular or cultural data to confirm this relationship have been lacking. The aim of this study was thus to resolve the relationship of these two genera by generating nucleotide sequence data for three loci, ITS, LSU and RPB2. Based on these results, Ceuthospora is reduced to synonymy under the older generic name Phacidium. Phacidiaceae (currently Helotiales) is suggested to constitute a separate order, Phacidiales (Leotiomycetes), as sister to Helotiales, which is clearly paraphyletic. Phacidiaceae includes Bulgaria, and consequently the family Bulgariaceae becomes a synonym of Phacidiaceae. Several new combinations are introduced in Phacidium, along with two new species, P. pseudophacidioides, which occurs on Ilex and Chamaespartium in Europe, and Phacidium trichophori, which occurs on Trichophorum cespitosum subsp. germanicum in The Netherlands. The generic name Allantophomopsiella is introduced to accommodate A. pseudotsugae, a pathogen of conifers, while Gremmenia is resurrected to accommodate the snow-blight pathogens of conifers, G. abietis, G. infestans, and G. pini-cembrae

Ευρετικές προσεγγίσεις του μοναδιάστατου προβλήματος πακετοποίησης

Article 59.1, of the International Code of Nomenclature for Algae, Fungi, and Plants (ICN; Melbourne Code), which addresses the nomenclature of pleomorphic fungi, became effective from 30 July 2011. Since that date, each fungal species can have one nomenclaturally correct name in a particular classification. All other previously used names for this species will be considered as synonyms. The older generic epithet takes priority over the younger name. Any widely used younger names proposed for use, must comply with Art. 57.2 and their usage should be approved by the Nomenclature Committee for Fungi (NCF). In this paper, we list all genera currently accepted by us in Dothideomycetes (belonging to 23 orders and 110 families), including pleomorphic and non-pleomorphic genera. In the case of pleomorphic genera, we follow the rulings of the current ICN and propose single generic names for future usage. The taxonomic placements of 1261 genera are listed as an outline. Protected names and suppressed names for 34 pleomorphic genera are listed separately. Notes and justifications are provided for possible proposed names after the list of genera. Notes are also provided on recent advances in our understanding of asexual and sexual morph linkages in Dothideomycetes. A phylogenetic tree based on four gene analyses supported 23 orders and 75 families, while 35 families still lack molecular data

Eucalyptus microfungi known from culture. 3. Eucasphaeria and Sympoventuria genera nova, and new species of Furcaspora, Harknessia, Heteroconium and Phacidiella

Members of the genus Eucalyptus represent a substrate richly colonized by numerous undescribed fungal species. Several species and genera of ascomycetes were collected from leaves or from leaf litter of this host genus in Australia and South Africa in the present study. New genera include Eucasphaeria capensis and Sympoventuria capensis (ascomycetes), genera et spp. nov. New species include Furcaspora eucalypti, Harknessia ipereniae, H. gibbosa, Heteroconium kleinziensis and Phacidiella eucalypti

Phoma basal rot of Romaine lettuce in California caused by Phoma exigua: Occurrence, characterization, and control

Beginning in 2000 and continuing into 2004, a previously undescribed disease caused significant damage to romaine lettuce (Lactuca sativa) in the coastal Salinas Valley of California. Symptoms were brownish black, sunken cavities on the crown and upper taproot. Cavities were firm, lacked signs of fungal growth, and resulted in cracking and weakening of the crown. Affected plants were stunted, uneven in growth, and unmarketable. Crisphead lettuce also developed these symptoms, although disease incidence was always lower than that for romaine. A fungus was consistently isolated from cavities. Using morphological features and molecular methods, the fungus was identified as Phoma exigua. Pathogenicity of isolates from romaine and crisphead lettuce was demonstrated on both of these lettuce types. Replicated field studies showed that azoxystrobin, boscalid, and cyprodinil + fludioxonil fungicides effectively controlled the disease. This is the first report of a crown disease caused by P. exigua in the United States. A similar disease, Phoma basal rot on greenhouse grown lettuce in the United Kingdom, had been previously observed, but no report has been published