Abstract
Plasmopara halstedii, cause of downy mildew of sunflower, is a pathogen of worldwide economic importance. Efforts to amplify the ITS-region from this organism revealed an unexpected fragment length of about 2600 bp, in contrast to about 900 bp, reported for other members of the Peronosporaceae. First attempts to obtain the complete sequence of the P. halstedii fragment were unsuccessful, due to repeated elements in ITS, which were uncovered later on. The presence of a single EcoRI-site allowed us to apply a restriction-ligation procedure to amplify parts of the ITS fragment separately. Sequencing of these fragments revealed the presence of four copies of a tandemly arranged repetitive element in the ITS-2 region. The complete sequence was obtained by using a sequencing primer which annealed shortly before the repetitions so covering the gap in the sequence around the restriction site. The ITS sequence in P. halstedii (AY773346) consisted of 2587 bp in total, with ITS-2 accounting for 2212 bp alone. This is the longest ITS-2 sequence reported so far for any examined species.
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References
M Bachofer (2004) Molekularbiologische Populationsstudien an Plasmopara halstedii, dem Falschen Mehltau der Sonnenblume SeriesTitleDissertation Universität Hohenheim Germany 1–140
M Göker H Voglmayr A Riethmüller M Weiß F Oberwinkler (2003) ArticleTitleTaxonomic aspects of Peronosporaceae inferred from Bayesian molecular phylogenetics Canadian Journal of Botany 81 672–683 Occurrence Handle10.1139/b03-066
TJ Gulya KY Rashid SM Masirevic (1997) Sunflower diseases, AA Schneiter (Eds) Agronomy 35: Sunflower Technology and Production ASA, CSSA, SSSA, Madison, WI USA 263–379
F Intelmann O Spring (2002) ArticleTitleAnalysis of total DNA by minisatellite and simple-sequence repeat primers for the use of population studies in Plasmopara halstedii Canadian Journal of Microbiology 48 555–559 Occurrence Handle10.1139/w02-046 Occurrence Handle12166683
L Medlin HJ Elwood S Stickel ML Sogin (1988) ArticleTitleThe characterization of enzymatically amplified eukaryotic 16S-like rRNA-coding regions Gene 71 491–499 Occurrence Handle10.1016/0378-1119(88)90066-2 Occurrence Handle3224833
JM Moncalvo HH Wang RS Hseu (1995) ArticleTitlePhylogenetic relationships in Ganoderma inferred from the internal transcribed spacers and 25S ribosomal DNA sequences Mycologia 87 223–223
AB Petersen S Rosendahl (2000) ArticleTitlePhylogeny of the Peronosporomycetes (Oomycetes) based on partial sequence of the large ribosomal subunit (LSU rDNA) Mycological Research 104 1295–1303 Occurrence Handle10.1017/S0953756200003075
A Riethmüller H Voglmayr M Göker M Weiß F Oberwinkler (2002) ArticleTitlePhylogenetic relationships of the downy mildews (Peronosporales) and related groups based on nuclear large subunit ribosomal DNA sequences Mycologia 94 834–849
P Roeckel-Drevet V Coelho J Tourvieille P Nicolas D Tourvieille Labrouhe Particlede (1997) ArticleTitleLack of genetic variability in French identified races of Plasmopara halstedii, the cause of downy mildew in sunflower Helianthus annuus Canadian Journal of Microbiology 43 260–263
P Roeckel-Drevet J Tourvieille TJ Gulya G Charmet P Nicolas D Tourvieille Labrouhe Particlede (2003) ArticleTitleMolecular variability of sunflower downy mildew, Plasmopara halstedii, from different continents Canadian Journal of Microbiology 49 492–502 Occurrence Handle10.1139/w03-062 Occurrence Handle14608384
WE Sackston (1981) Downy mildew of sunflower DM Spencer (Eds) The Downy Mildews Academic Press London, UK 545–575
O Spring H Voglmayr A Riethmüller F Oberwinkler (2003) ArticleTitleCharacterization of a Plasmopara isolate from Helianthus × laetiflorus based on cross infection, morphological, fatty acids, and molecular phylogenetic data Mycological Progress 2 163–170
H Voglmayr (2003) ArticleTitlePhylogenetic study of Peronospora and related genera based on nuclear ribosomal ITS sequences Mycological Research 107 1132–1142 Occurrence Handle10.1017/S0953756203008438 Occurrence Handle14635762
P Vos R Hogers M Bleeker M Reijans T Lee Particlevan de M Hornes A Freiters J Pot J Peleman M Kuiper M Zabeau (1995) ArticleTitleAFLP: a new technique for DNA fingerprinting Nucleic Acids Research 23 4407–4414 Occurrence Handle7501463
TJ White T Bruns S Lee JW Taylor (1990) Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics MA Innis DH Gelfand JJ Sninsky TJ White (Eds) PCR Protocols: A Guide to Methods and Applications Academic Press New York, USA 315–322
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Thines, M., Komjáti, H. & Spring, O. Exceptional length of ITS in Plasmopara halstedii is due to multiple repetitions in the ITS-2 region. Eur J Plant Pathol 112, 395–398 (2005). https://doi.org/10.1007/s10658-005-6606-6
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DOI: https://doi.org/10.1007/s10658-005-6606-6