Structure of populations of wheat powdery mildew (Erysiphe graminis DC f.sp. tritici Marchal) in central Europe in 1993-1996. I. Dynamics of virulence

• Published in: European journal of plant pathology Vol. 104; no. 6; pp. 537 - 544
• Main Authors: Svec, M, Miklovicova, M
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01-08-1998; Springer Nature B.V
• Subjects: Airborne microorganisms; Biological and medical sciences; disease resistance; Erysiphe graminis; Erysiphe graminis f. sp. tritici; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; genes; Genetics; geographical distribution; Pathogens; Pathology, epidemiology, host-fungus relationships. Damages, economic importance; pathotypes; Phytopathology. Animal pests. Plant and forest protection; Plant diseases; plant pathogenic fungi; Plant pathology; Plant populations; population; provenance; resistance genes; stabilizing selection; Triticum; Triticum aestivum; virulence; Wheat; Czech Republic; Austria; Slovakia; Hungary; Central Europe; Europe; Monocotyledones; Erysiphe graminis f. tritici; Plant pathogen; Virulence; Population structure; Cereal crop; Fungi; Population survey; Gene; Gramineae; Dynamics; Angiospermae; Ascomycetes; Spermatophyta; Triticum aestivum; Thallophyta
• ISSN: 0929-1873; 1573-8469
• DOI: 10.1023/A:1008642816326

In 1993-1996, the virulence of regional populations of the wheat powdery mildew pathogen (Erysiphe graminis DC f. sp. tritici Marchal) from the Czech Republic, Austria, Hungary and Slovakia against 13 resistance genes was investigated. The populations differed mainly at the regional level. Populations from the Czech Republic, mainly from the western regions, showed higher values of virulence against the Pm4b gene. Lower frequency of virulence against Pm4b was found in Austria, and the lowest value was observed in Hungary. The differences in frequencies of virulence against Pm4a and Pm4b showed a similar geographic pattern across the four countries: a continuous decline from west to east and from north to south. Virulence against Pm2 decreased in all countries considered; virulence to pm5, Pm6, Pm8 and Mli was high throughout. Genes and gene combinations that can ensure a relatively effective biological protection against this pathogen across Central Europe at present are Pm3b, Pm2+Mld and Pm1+2+9. Czech and Slovak populations were the most complex: virulence complexity reached a maximum in Slovakia in 1994. A similar evolution, though less significant, was observed in the Czech Republic. Data on complexity of isolates suggest that Central European populations of wheat powdery mildew tend to reach an intermediate level representing the optimal number of virulence genes. This process is probably a consequence of stabilizing selection.[PUBLICATION ABSTRACT]