European Journal of Plant Pathology

, Volume 132, Issue 1, pp 111–122 | Cite as

Frequency of mutations associated with fungicide resistance and population structure of Mycosphaerella graminicola in Tunisia

  • Sameh Boukef
  • Bruce A. McDonald
  • Amor Yahyaoui
  • Salah Rezgui
  • Patrick C. Brunner


The occurrence of fungicide resistance in Mycosphaerella graminicola populations from Tunisia was investigated by examining mutations known to be associated with strobilurin and azole resistance. Few mutations associated with fungicide resistance were detected. No evidence for strobilurin resistance was found among 357 Tunisian isolates and only two among 80 sequenced isolates carried mutations associated with azole resistance. A network analysis suggested that these mutations emerged independently from mutations found in previously described European populations. The population genetic structure of M. graminicola in Tunisia was analyzed using variation at 11 microsatellite loci. Populations in Tunisia were characterized by high gene and genotype diversity. All populations were in gametic equilibrium and mating type proportions did not deviate from the 1:1 ratio expected under random mating, consistent with regular cycles of sexual reproduction. In combination with a high degree of gene flow among sampling sites, M. graminicola must be considered a pathogens with high evolutionary potential. Thus, control strategies against Septoria blotch in Tunisia should be optimized to reduce the emergence and spread of resistant isolates.


DMI fungicides Gene flow QoI fungicides Parallel evolution Septoria tritici 



We thank Marcello Zala, Stefano Torriani, Megan McDonald and Joanna Bernardes de Assis for technical support and helpful discussions. The Genetic Diversity Center of ETH Zurich provided facilities for collecting molecular data. This project was supported by the Swiss government through the Federal Commission for Scholarships for Foreign Students (FCS; RefNr: 20080384) who sponsored SB.

Supplementary material

10658_2011_9853_MOESM1_ESM.doc (158 kb)
Supplementary Table S1 Geographic distribution of 24 observed CYP51 haplotypes in M. graminicola collected in Tunisia. (DOC 158 kb)
10658_2011_9853_MOESM2_ESM.doc (84 kb)
Supplementary Fig. S1 Nucleotide sequence variation from 1358 bp of the CYP51 gene from 80 M. graminicola isolates defining 24 distinct haplotypes. Sites are numbered according to their position in the reference sequence ST1 (GenBank accession AY730587). Small letters represent silent nucleotide variations and capital letters indicate variations that alter the amino acid composition. Resistant haplotypes are shaded in grey with the corresponding resistance mutations (see also Supplementary Table S1). (DOC 83 kb)


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Copyright information

© KNPV 2011

Authors and Affiliations

  • Sameh Boukef
    • 1
  • Bruce A. McDonald
    • 2
  • Amor Yahyaoui
    • 3
  • Salah Rezgui
    • 1
  • Patrick C. Brunner
    • 2
  1. 1.Laboratoire de Génétique et d’Amélioration des Plantes, Institut National Agronomique de TunisTunisTunisia
  2. 2.Institute of Integrative Biology, ETH ZurichZurichSwitzerland
  3. 3.International Center for Agricultural Research in the Dry Areas (ICARDA)AleppoSyria

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