title: Sensitivity of Fusarium culmorum to triazoles: impact of trichothecene chemotypes, oxidative stress response and genetic diversity.
abstract: BACKGROUND
  Fusarium culmorum is a fungal pathogen occurring worldwide on various weeds and important crops. Triazoles have been shown to be the most effective fungicide for managing Fusarium spp., but little is known about their specific activity on F. culmorum.
  
  
  RESULTS
  The sensitivity of 107 F. culmorum strains to triazoles was assessed using microtitre plate assays. The EC50values ranged from 0.14 to 1.53 mg L-1for tebuconazole and from 0.25 to 2.47 mg L-1for epoxiconazole. Cross-resistance to both azoles was found (r = 0.61). F. culmorum appeared to be significantly more sensitive than F. graminearum or F. cerealis. No increase in the mean EC50was observed over time, which might be related to an unfavourable fitness cost, measured here as fungal growth. On average, nivalenol-producing strains of F. culmorum were significantly more resistant than deoxynivalenol-producing strains. The relationship between resistance and chemotype-dependent adaptation to oxidative stress was investigated, but remained unclear. No link between inter-simple sequence repeat (ISSR) genetic diversity and triazole resistance could be established.
  
  
  CONCLUSIONS
  Fungicide use might not be a driving force in the evolution of F. culmorum, and the benefit of a resistance trait probably does not outweigh its costs. © 2016 Society of Chemical Industry.
authors.affiliation: Université Catholique de Louvain - Earth and Life Institute, Applied Microbiology, Phytopathology, Louvain-la-Neuve, Belgium.
authors.forename: Pierre
authors.identifier: http://orcid.org/0000-0003-4777-6036
authors.initials: P
authors.lastname: Hellin
authors.affiliation: Université Catholique de Louvain - Earth and Life Institute, Applied Microbiology, Phytopathology, Louvain-la-Neuve, Belgium.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Scauflaire
authors.affiliation: Université Catholique de Louvain - Earth and Life Institute, Applied Microbiology, Phytopathology, Louvain-la-Neuve, Belgium.
authors.forename: Viviane
authors.initials: V
authors.lastname: Van Hese
authors.affiliation: Université Catholique de Louvain - Earth and Life Institute, Applied Microbiology, Phytopathology, Louvain-la-Neuve, Belgium.
authors.forename: Françoise
authors.initials: F
authors.lastname: Munaut
authors.affiliation: Université Catholique de Louvain - Earth and Life Institute, Applied Microbiology, Phytopathology, Louvain-la-Neuve, Belgium.
authors.forename: Anne
authors.initials: A
authors.lastname: Legrève
mesh_terms: D005659:Fungicides, Industrial / Q000494:pharmacology*; D005670:Fusarium / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D014644:Genetic Variation; D018384:Oxidative Stress; D014230:Triazoles / Q000494:pharmacology*; D014255:Trichothecenes / Q000096:biosynthesis
chemical_list: D005659:Fungicides, Industrial; D014230:Triazoles; D014255:Trichothecenes
keywords: DMI fungicide; ISSR fingerprinting; chemotype; mating type; resistance