title: Detection of Zymoseptoria tritici SDHI-insensitive field isolates carrying the SdhC-H152R and SdhD-R47W substitutions.
abstract: BACKGROUND
  Succinate dehydrogenase inhibitor (SDHI) fungicides are important in the management of Zymoseptoria tritici in wheat. New active ingredients from this group of fungicides have been introduced recently and are widely used. Because the fungicides act at a single enzyme site, resistance development in Z. tritici is classified as medium-to-high risk.
  
  
  RESULTS
  Isolates from Irish experimental plots in 2015 were tested against the SDHI penthiopyrad during routine monitoring. The median of the population was approximately 2 times less sensitive than the median of the baseline population. Two of the 93 isolates were much less sensitive to penthiopyrad than the least sensitive of the baseline isolates. These isolates were also insensitive to most commercially available SDHIs. Analysis of the succinate dehydrogenase coding genes confirmed the presence of the substitutions SdhC-H152R and SdhD-R47W in the very insensitive isolates.
  
  
  CONCLUSIONS
  This is the first report showing that the SdhC-H152R mutation detected in laboratory mutagenesis studies also exists in the field. The function and relevance of this mutation, combined with SdhD-R47W, still needs to be determined. © 2016 Society of Chemical Industry.
authors.affiliation: Department of Crop Science, TEAGASC Crops, Environment and Land Use Programme, Carlow, Republic of Ireland.|School of Agriculture, Policy and Development, University of Reading, Reading, UK.
authors.forename: Hilda
authors.initials: H
authors.lastname: Dooley
authors.affiliation: School of Agriculture, Policy and Development, University of Reading, Reading, UK.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Shaw
authors.affiliation: Department of Crop Science, TEAGASC Crops, Environment and Land Use Programme, Carlow, Republic of Ireland.
authors.forename: Jeanne
authors.initials: J
authors.lastname: Mehenni-Ciz
authors.affiliation: Department of Crop Science, TEAGASC Crops, Environment and Land Use Programme, Carlow, Republic of Ireland.
authors.forename: John
authors.initials: J
authors.lastname: Spink
authors.affiliation: Department of Crop Science, TEAGASC Crops, Environment and Land Use Programme, Carlow, Republic of Ireland. stephen.kildea@teagasc.ie.
authors.forename: Steven
authors.initials: S
authors.lastname: Kildea
mesh_terms: D019943:Amino Acid Substitution; D001203:Ascomycota / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D025141:Drug Resistance, Fungal / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005659:Fungicides, Industrial / Q000494:pharmacology*; D007494:Ireland; D009154:Mutation; D010935:Plant Diseases / Q000382:microbiology; D011720:Pyrazoles / Q000494:pharmacology; D013385:Succinate Dehydrogenase / Q000037:antagonists & inhibitors / Q000235:genetics*; D013876:Thiophenes / Q000494:pharmacology; D014908:Triticum / Q000382:microbiology
chemical_list: D004791:Enzyme Inhibitors; D005659:Fungicides, Industrial; D011720:Pyrazoles; D013876:Thiophenes; D013385:Succinate Dehydrogenase; C539106:penthiopyrad
keywords: Mycosphaerella graminicola; Zymoseptoria tritici; amino acid mutation; fungicide resistance; septoria tritici blotch; succinate dehydrogenase inhibitor