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Species concepts in Cercospora: spotting the weeds among the roses.

Groenewald JZ, Nakashima C, Nishikawa J, Shin HD, Park JH, Jama AN, Groenewald M, Braun U, Crous PW - Stud. Mycol. (2013)

Bottom Line: Some species were found to be limited to a specific host genus, whereas others were isolated from a wide host range.No single locus was found to be the ideal DNA barcode gene for the genus, and species identification needs to be based on a combination of gene loci and morphological characters.Takim., Cercospora sojina Hara.

View Article: PubMed Central - PubMed

Affiliation: CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.

ABSTRACT

Unlabelled: The genus Cercospora contains numerous important plant pathogenic fungi from a diverse range of hosts. Most species of Cercospora are known only from their morphological characters in vivo. Although the genus contains more than 5 000 names, very few cultures and associated DNA sequence data are available. In this study, 360 Cercospora isolates, obtained from 161 host species, 49 host families and 39 countries, were used to compile a molecular phylogeny. Partial sequences were derived from the internal transcribed spacer regions and intervening 5.8S nrRNA, actin, calmodulin, histone H3 and translation elongation factor 1-alpha genes. The resulting phylogenetic clades were evaluated for application of existing species names and five novel species are introduced. Eleven species are epi-, lecto- or neotypified in this study. Although existing species names were available for several clades, it was not always possible to apply North American or European names to African or Asian strains and vice versa. Some species were found to be limited to a specific host genus, whereas others were isolated from a wide host range. No single locus was found to be the ideal DNA barcode gene for the genus, and species identification needs to be based on a combination of gene loci and morphological characters. Additional primers were developed to supplement those previously published for amplification of the loci used in this study.

Taxonomic novelties: New species - Cercospora coniogrammes Crous & R.G. Shivas, Cercospora delaireae C. Nakash., Crous, U. Braun & H.D. Shin, Cercospora euphorbiae-sieboldianae C. Nakash., Crous, U. Braun & H.D. Shin, Cercospora pileicola C. Nakash., Crous, U. Braun & H.D. Shin, Cercospora vignigena C. Nakash., Crous, U. Braun & H.D. Shin. Typifications: epitypifications - Cercospora alchemillicola U. Braun & C.F. Hill, Cercospora althaeina Sacc., Cercospora armoraciae Sacc., Cercospora corchori Sawada, Cercospora mercurialis Pass., Cercospora olivascens Sacc., Cercospora violae Sacc.; neotypifications - Cercospora fagopyri N. Nakata & S. Takim., Cercospora sojina Hara.

No MeSH data available.


Related in: MedlinePlus

(Part 1). Consensus phylogram (50 % majority rule) of 5 994 trees resulting from a Bayesian analysis of the combined 5-gene sequence alignment using MrBayes v. 3.2.0. Bayesian posterior probabilities are indicated with colour-coded branches and numbers (see legend) and the scale bar represents the expected changes per site. Species clades are indicated in coloured blocks and species names in black text. Hosts and countries of origin are indicated in green and blue text, respectively. The tree was rooted to Septoria provencialis (strain CPC 12226).
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Figure 2: (Part 1). Consensus phylogram (50 % majority rule) of 5 994 trees resulting from a Bayesian analysis of the combined 5-gene sequence alignment using MrBayes v. 3.2.0. Bayesian posterior probabilities are indicated with colour-coded branches and numbers (see legend) and the scale bar represents the expected changes per site. Species clades are indicated in coloured blocks and species names in black text. Hosts and countries of origin are indicated in green and blue text, respectively. The tree was rooted to Septoria provencialis (strain CPC 12226).

Mentions: Isolates of Cercospora sp. Q were screened with five more loci to test whether additional loci could distinguish cryptic taxa within this species. This species was selected based on the intraspecific variation present in Fig. 2 (part 5) and also the range of host species and countries represented. The primer set GDF1 and GDR1 (Guerber et al. 2003) was used to amplify part of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, primer set NMS1 and NMS2 (Li et al. 1994) for part of the mitochondrial small subunit rRNA gene and part of the chitin synthase (CHS) gene was amplified using the primers CHS-79F and CHS-354R (Carbone & Kohn 1999). Part of the gene encoding for a mini-chromosome maintenance protein (MCM7) was amplified using primers Mcm7-709for, Mcm7-1348rev, Mcm7-1447rev (Schmitt et al. 2009) and part of the beta-tubulin gene using mainly the primers T1, Bt2b and TUB3Rd (see Table 2 for references).


Species concepts in Cercospora: spotting the weeds among the roses.

Groenewald JZ, Nakashima C, Nishikawa J, Shin HD, Park JH, Jama AN, Groenewald M, Braun U, Crous PW - Stud. Mycol. (2013)

(Part 1). Consensus phylogram (50 % majority rule) of 5 994 trees resulting from a Bayesian analysis of the combined 5-gene sequence alignment using MrBayes v. 3.2.0. Bayesian posterior probabilities are indicated with colour-coded branches and numbers (see legend) and the scale bar represents the expected changes per site. Species clades are indicated in coloured blocks and species names in black text. Hosts and countries of origin are indicated in green and blue text, respectively. The tree was rooted to Septoria provencialis (strain CPC 12226).
© Copyright Policy - creative-commons
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3713887&req=5

Figure 2: (Part 1). Consensus phylogram (50 % majority rule) of 5 994 trees resulting from a Bayesian analysis of the combined 5-gene sequence alignment using MrBayes v. 3.2.0. Bayesian posterior probabilities are indicated with colour-coded branches and numbers (see legend) and the scale bar represents the expected changes per site. Species clades are indicated in coloured blocks and species names in black text. Hosts and countries of origin are indicated in green and blue text, respectively. The tree was rooted to Septoria provencialis (strain CPC 12226).
Mentions: Isolates of Cercospora sp. Q were screened with five more loci to test whether additional loci could distinguish cryptic taxa within this species. This species was selected based on the intraspecific variation present in Fig. 2 (part 5) and also the range of host species and countries represented. The primer set GDF1 and GDR1 (Guerber et al. 2003) was used to amplify part of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, primer set NMS1 and NMS2 (Li et al. 1994) for part of the mitochondrial small subunit rRNA gene and part of the chitin synthase (CHS) gene was amplified using the primers CHS-79F and CHS-354R (Carbone & Kohn 1999). Part of the gene encoding for a mini-chromosome maintenance protein (MCM7) was amplified using primers Mcm7-709for, Mcm7-1348rev, Mcm7-1447rev (Schmitt et al. 2009) and part of the beta-tubulin gene using mainly the primers T1, Bt2b and TUB3Rd (see Table 2 for references).

Bottom Line: Some species were found to be limited to a specific host genus, whereas others were isolated from a wide host range.No single locus was found to be the ideal DNA barcode gene for the genus, and species identification needs to be based on a combination of gene loci and morphological characters.Takim., Cercospora sojina Hara.

View Article: PubMed Central - PubMed

Affiliation: CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.

ABSTRACT

Unlabelled: The genus Cercospora contains numerous important plant pathogenic fungi from a diverse range of hosts. Most species of Cercospora are known only from their morphological characters in vivo. Although the genus contains more than 5 000 names, very few cultures and associated DNA sequence data are available. In this study, 360 Cercospora isolates, obtained from 161 host species, 49 host families and 39 countries, were used to compile a molecular phylogeny. Partial sequences were derived from the internal transcribed spacer regions and intervening 5.8S nrRNA, actin, calmodulin, histone H3 and translation elongation factor 1-alpha genes. The resulting phylogenetic clades were evaluated for application of existing species names and five novel species are introduced. Eleven species are epi-, lecto- or neotypified in this study. Although existing species names were available for several clades, it was not always possible to apply North American or European names to African or Asian strains and vice versa. Some species were found to be limited to a specific host genus, whereas others were isolated from a wide host range. No single locus was found to be the ideal DNA barcode gene for the genus, and species identification needs to be based on a combination of gene loci and morphological characters. Additional primers were developed to supplement those previously published for amplification of the loci used in this study.

Taxonomic novelties: New species - Cercospora coniogrammes Crous & R.G. Shivas, Cercospora delaireae C. Nakash., Crous, U. Braun & H.D. Shin, Cercospora euphorbiae-sieboldianae C. Nakash., Crous, U. Braun & H.D. Shin, Cercospora pileicola C. Nakash., Crous, U. Braun & H.D. Shin, Cercospora vignigena C. Nakash., Crous, U. Braun & H.D. Shin. Typifications: epitypifications - Cercospora alchemillicola U. Braun & C.F. Hill, Cercospora althaeina Sacc., Cercospora armoraciae Sacc., Cercospora corchori Sawada, Cercospora mercurialis Pass., Cercospora olivascens Sacc., Cercospora violae Sacc.; neotypifications - Cercospora fagopyri N. Nakata & S. Takim., Cercospora sojina Hara.

No MeSH data available.


Related in: MedlinePlus