Abstract
Genetic variability and population structure ofCercospora beticola, the causal agent of Cercospora leaf spot in sugarbeet, from four sugarbeet-growing regions of Greece were investigated using growth rate, pathogenicity, and mini- and microsatellite DNA fingerprinting. Mycelial growth and pathogenicity were very diverse within and between groups, and no correlation was found between these features and the geographic origin of the isolates. High diversity was found by micro- and minisatellite fingerprinting, with an average gene diversity of 0.21, and no significant differences among populations. Among the 46 isolates, 45 different genotypes were identified, showing a high degree of genotype diversity. Analysis of the genetic profiles provided no evidence for regional patterns of variation (ΦFST=0.01, P=0.261) and the analysis of molecular variation (AMOVA) revealed that genetic variability was due mainly to variations within (99%) rather than between (1%) populations. Such a low level of genetic differentiation is reflected by a migration rate value Nm of 4.7. The high migration rate cannot be referred to splash dispersed conidia. To justify the absence of a regional structure in these C.beticola populations, we must suppose the existence of a long-distance means of dispersal, such as seed transmission and/or man mediated transmission.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Cai G., Schneider R.W. (2005). Vegetative compatibility groups in Cercosporakikuchii, the causal agent of cercospora leaf blight and purple seed stain in soybean. Phytopathology, 95: 257–261.
Duffus J.E., Ruppel E.G. (1993). Diseases. In: Cooke D.A., Scott R.K., Eds, The Sugar Beet Crop. Science Into Practice. Chapman and Hall, London, pp. 347–427.
Excoffier L., Smouse P., Quattro J. (1992). Analysis of molecular variance inferred from metric distances among DNA haplotypes: application human mithocondrial DNA restriction data. Genetics, 131: 479–491.
Goodwin S.B., Dunkle L.D., Zismann V.L. (2001). Phylogenetic analysis of Cercospora andMycosphaerella based on the internal transcribed spacer region of ribosomal DNA. Phytopathology, 91: 648–658.
Goodwin S.B., Waalwijk C., Kema G.H.J., Cavaletto J.R., Zhang G. (2003). Cloning and analysis of the mating-type idiomorphs from the barley pathogenSeptoria passerinii. Mol. Genet. Genomics, 269: 1–12.
Kelly A.C., Bainbridge B.W., Heale Y.B., Perez-Artes E., Jimenez-Diaz R.M. (1998).In planta-Polymerase-Chain-Reaction detection of the wilt inducing pathotype ofFusarium oxysporum f.sp. ciceris in chich pea (Cicer arietinum L.). Physiol. Mol. Plant Pathol., 52: 397–409.
Lawrence J.S., Meredith D.S. (1970). Wind dispersal of conidia ofCercospora beticola. Phytopathology, 60: 1076–1078.
McDermont J.M., McDonald B.A., Allard R.W., Webster R.K. (1989). Genetic variability for pathogenicity, isozyme, ribosomal DNA and colony color variants in populations ofRhynchosporium secalis. Genetics, 122: 561–565.
McDermont J.M., McDonald B.A. (1993). Gene flow in plant pathosystems. Ann. Rev. Phytopathol., 31: 353–373.
McDonald B.A. (1997). The population genetics of fungi: tools and techniques. Phytopathology, 87: 448–453.
McDonald B.A., Linde C. (2002). Pathogen population genetics, evolutionary potential, and durable resistance. Ann. Rev. Phytopathol., 40: 349–379.
McKay M.B., Pool V.W. (1918). Field studies ofCercospora beticola. Phytopathology, 8: 119–136.
Milgroom M.G. (1996). Recombination and the multilocus structure of fungal populations. Ann. Rev. Phytopathol., 34: 457–477.
Milgroom M.G., Fry W.E. (1997). Contributions of population genetics to plant disease epidemiology and management. Adv. Bot. Res., 24: 1–30.
Moretti M., Saracchi M., Farina G. (2004). Morphological, physiological and genetic diversity within a small population ofCercospora beticola Sacc. Ann. Microbiol., 54: 129–150.
Nei M. (1972). Genetic distance between populations. Amer. Natur., 106: 283–292.
Nei M. (1973). Analysis of gene diversity in subdivided populations. Proc. Natl. Acad. Sci. USA, 70: 3321–3323.
Nei M. (1978). Estimation of average heterozygosity and genetic distance from a small number of individuals. Genetics, 89: 583–590.
Okori P., Fahleson J., Rubaihayo P.R., Adipala E., Dixelius C. (2003). Assessment of genetic variation among East AfricanCercospora zeae-maydis populations. Afr. Crop Sci. J., 11: 75–85.
Okori P., Rubaihayo P.R., Ekwamu A., Fahleson J., Dixelius C. (2004). Genetic characterization of Cercospora sorghi from cultivated and wild sorghum and its relationship to otherCercospora fungi. Phytopathology, 94: 743–750.
Peakall R., Smouse P.E. (2001). GenAlEx V5: genetic analysis in Excel. Population genetic software for teaching and research. Australian National University, Canberra, Australia.
Ruppel E.G. (1972). Variation among isolates ofCercospora beticola from sugar beet. Phytopathology, 62: 134–136.
Ruppel E.G. (1986). Cercospora leaf spot. In: Whitney E.D., Duffus J.E., Eds, Compendium of Beet Diseases and Insects. American Phytopathological Society, St. Paul, MN, pp. 8–9.
Salamati S., Zhan J., Burdon J.J., McDonald B.A. (2000). The genetic structure of field populations ofRhynchosporium secalis from three continents suggests moderate gene flow and regular recombination. Phytopathology, 90: 901–908.
Sanders I. (1999). No sex please, we are fungi. Nature, 399: 737–739.
Setiawan A., Koch G., Barnes S.R., Jung C. (2000). Mapping quantitative trait loci (QTLs) for resistance to Cercospora leaf spot disease (Cercospora beticola Sacc.) in sugar beet. Theor. Appl. Genet., 100: 1176–1182.
Shane W.W., Teng P.S. (1992). Impact of Cercospora leaf spot on root weight, sugar yield, and purity ofBeta vulgaris. Plant Dis., 76: 812–820.
Stoddart J.A., Taylor J.F. (1988). Genotypic diversity: estimation and prediction in samples. Genetics, 118: 705–711.
Tuite J. (1969). Plant Pathological Methods — Fungi and Bacteria. Burgess Publ. Co., Minneapolis, Minnesota.
Van der Waals J.E., Korsten L., Slippers B. (2004). Genetic diversity amongAlternaria solani isolates from potatoes in South Africa. Plant Dis., 88: 959–964.
Vereijssen J., Schneider H.J.H.M., Termorshuizen A.A.J. (2004). Possible root infection ofCercospora beticola in sugar beet. Eur. J. Plant Pathol., 110: 103–106.
Weiland J., Koch G. (2004). Sugarbeet leaf spot disease (Cercospora beticola Sacc.). Mol. Plant Pathol., 5: 157–166.
Weiland J., Eide J., Rivera-Varas V., Secor G. (2001). Genetic diversity ofCercospora beticola in the U.S. and association of molecular markers with tolerance to the fungicide triphenyltin hydroxide (TPTH). Phytopathology, 91: 94 (abstract).
Weising K., Nybom H., Wolff K., Meyer W., Eds (1995). DNA fingerprinting in plants and fungi. CRC Press, Boca Raton.
Whitney E.D., Lewellen R.T. (1976). Identification and distribution of races C1 and C2 ofCercospora beticola from sugarbeet. Phytopathology, 66: 1158–1160.
Zamani M.R., Motallebi M., Rostamian A. (2004). Characterization of Iranian isolates ofFusarium oxysporum on the basis of RAPD analysis, pathogenicity, and vegetative compatibility. J. Phytopathol., 152: 499–503.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Moretti, M., Karaoglanidis, G., Saracchi, M. et al. Analysis of genotypic diversity inCercospora beticola Sacc. field isolates. Ann. Microbiol. 56, 215–221 (2006). https://doi.org/10.1007/BF03175008
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF03175008