Abstract
The powdery mildew fungi (Erysiphales) are a common group of obligate plant pathogens that can be extremely difficult to identify, depending on the reproductive stage encountered, The ribosomal DNA Internal Transcribed Spacer (ITS) region was assessed for its usefulness to link anamorphic Erysiphales with their respective teleomorphs. PCR primers for the rDNA ITS region were designed and found to have enhanced specificity for the 12 genera tested, even in the presence of contaminating fungi. Recent herbarium specimens of both anamorphic and teleomorphic material yielded sufficient DNA for amplification using a Chelex-based extraction method. The ITS regions from 25 anamorphic specimens were sequence d and compared with the ITS sequences of their suspected teleomorphs. In most cases, an ITS region sequence similarity of above 99% indicated that a correct match had been made, although a specimen on Phlox could not be identified and a somewhat unexpected match was made between a specimen on Convolvulus and the celery powdery mildew (Erysiphe heraclei). Although this technique will not always unambiguously identify an anamorphic specimen, it will provide valuable information to use in conjunction with morphological and host range data to aid in the final identification.
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References
Alexcpolous CJ, Mims CW, Blackwell M (1996) ‘Introductory mycology (4th edn).’ (John Wiley and Sons Inc.: New York)
Altschul SF, Gish W, Miller W, Myers E, Lipmann OJ (1990) Basic local alignment search tool. Journal of Molecular Biology 219, 403.
Blumer S (1967) ‘Echte Mehltaupilze (Erysiphaceae).’ (Fischer: Jena)
Boesewinkel HJ (1980) The morphology of the imperfect states of powdery mildews (Erysiphaceae). Botanical Review 46, 167–224.
Braun U (1987) A monograph of the Erysiphales (powdery mildews). Nova Hedwigia 89, 1–700.
Braun U (1998) Neufunde Echter Mehltaupilze (Erysiphales) aus der BR Deutschland. Schlechtendalia 1, 31–40.
Braun U, Cook RTA, Inman AJ, Shin HD (2002) The taxonomy of the powdery mildew fungi. In ‘Powdery mildews: a comprehensive treatise’. (Eds R Belanger, AJ Dik, WR Bushnell) pp. 13–54. (APS Press: St Paul, USA)
Bruns TD, Fogel R, Taylor JW (1990) Amplification and sequencing of DNA from fungal herbarium specimens. Mycologia 82, 175–184.
Bruns TD, White TJ, Taylor JW (1991) Fungal molecular systematics. Annual Revue of Ecology and Systematics 22, 525–564.
Camara MPS, O’Neill NR, Van Berkum P (2002) Phylogeny of Stemphylium based on ITS and glyceraldehyde-3-phosphate sequences. Mycologia 94, 660–672.
Crous PW, Kang J-C, Schoch CL, Mchau GRA (1999) Phylogenetic relationships of Cylindrocladium pseudogracile and Cylindrocladium rumohrae with morphologically similar taxa, based on morphology and DNA sequences of internal transcribed spacers and beta-tubulin. Canadian Journal of Botany 77, 1813–1820.
De Jong SN, Levesque CA, Verkley GJM, Abeln ECA, Rahe JE, Braun PG (2001) Phylogenetic relationships among Neofabraea species causing tree cankers and bulls-eye rot of apples based on DNA sequencing of ITS nuclear rDNA, mitochondrial rDNA, and the β-tubulin gene. Mycological Research 105, 658–669.
Demeke T, Adams RP (1992) The effects of plant polysaccharides and buffer additives on PCR. Biotechniques 12, 332–334.
Haines JH, Cooper CR (1993) DNA and mycological herbaria. In ‘The fungal holomorph: mitotic, meiotic and pleomorphic speciation in fungal systematics’. (Eds DR Renolds, JW Taylor) pp. 305–315. (CAB International: Wallingford)
Hirata T, Takamatsu S (1996) Nucleotide sequence diversity of rDNA internal transcribed spacers extracted from conidia and cleistothecia from several powdery mildew fungi. Mycoscience 37, 283–288.
Innis MA, Gelfand DH (1990) Optimization of PCRs. In ‘PCR protocols: a guide to methods and applications’. (Eds MA Innis, DH Gelfand, JJ Sninsky, TJ White) pp. 3–12. (Academic Press Inc.: San Diego, California, USA)
Kang J-C, Crous PW, Mchau GRA, Serdani M, Song S-M (2002) Phylogenetic analysis of Alternaria spp. associated with apple core rot and citrus black rot in South Africa. Mycological Research 106, 1151–1162.
Kwok S, Kellogg DE, McKinnery N, Spasic D, Gada L, Levenson C, Sninsky JJ (1990) Effects of primer-template mismatches on the polymerase chain reaction: human immunodeficiency virus type 1 model studies. Nucleic Acids Research 18, 999–1005.
Lieckfeldt E, Seifert KA (2000) An evaluation of the use of ITS sequences in the taxonomy of the Hypocreales. Studies in Mycology 45, 35–44.
Saenz G, Taylor J (1999) Phylogeny of the Erysiphales (powdery mildews) inferred from internal transcribed spacer (ITS) ribosomal DNA sequences. Canadian Journal of Botany 77, 150–169.
Saenz G, Taylor J, Gargas A (1994) 18S rRNA gene sequences and supraordinal classification of the Erysiphales. Mycolog ia 86, 212- 216.
Salmon ES (1900) A monograph of the Erysiphaceae. Bulletin of the Torrey Botanical Club 9, 1–292.
Samuels GJ, Seifert KA (1995) The im pact of molecular characters on systematics of filamentous ascomycetes. Annual Review of Phytopathology 33, 37–67.
Simon MC, Gray DI, Cook N (1996) DNA extraction and PCR methods for the detection of Listeria monocytogenes in cold-smoked salmon. Applied and Environmental Microbiology 62, 822–844.
Takamatsu S, Hirata T, Sato Y (1998) Phylogenetic analysis and predicted secondary structures of the rDNA internal transcribed spacers of the powdery mildew fungi (Erysiphaceae). Mycoscience 39, 441–453.
Takamatsu S, Hirata T, Sato Y, Nomura Y (1999) Phylogenetic relationship of Microsphaera and Erysiphe sect. Erysiphe (powdery mildews) inferred from the rDNA ITS sequences. Mycoscience 39, 259–298.
Thompson JD, Higgins DG, Gibson TJ (1994) Clustal W: improving the sensitivity of progressive multiple progressive sequence alignment through sequence weighting, position specific gap penalties and weight matrix choice. Nucleic Acids Research 22, 4673–4680.
Walker J (1983) Pacific mycogeography: deficiencies and irregularities in the distribution of plant parasitic fungi. In ‘Pacif ic mycogeography: a preliminary approach’. (Eds KA Pirozynski, J Walker) pp. 89-136. Australian Journal of Botany. Supplementary Series No. 10.
White CG (1970) Production of powdery mildew cleistocarps in a controlled environment. Transactions of the British Mycological Society 55, 355–365.
White TJ, Bruns TD, Lee S, Taylor JW (1990) Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In ‘PCR protocols: a guide to methods and applications’. (Eds MA Innis, DH Gelfand, JJ Sninsky, TJ White) pp. 315–322. (Academic Press Inc: San Diego, California, USA)
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Cunnington, J.H., Takamatsu, S., Lawrie, A.C. et al. Molecular identification of anamorphic powdery mildews (Erysiphales). Australasian Plant Pathology 32, 421–428 (2003). https://doi.org/10.1071/AP03045
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DOI: https://doi.org/10.1071/AP03045