EuroWheat campaign about Azole resistance in Europe

EuroWheat partners- includes industry partners - work together on monitoring the level and evolution of fungicide resistance related to the Azole control of Zymoseptoria tritici causing Septoria Tritici Blotch (STB), which causes significant losses in wheat. In some parts of Europe we find a decrease in the efficacy of a major group of fungicides currently used.

Azoles have different strengths and perform diversely across Europe. A Eurowheat campaign are comparing the efficacy profile of azoles on the main diseases in winter wheat in different regions and climate zones of Europe. The project target STB and rust diseases. The work also includes a characterization of pathogen populations in order to get a better understanding of observed differences or similarities in obtained fungicide efficacy profiles.

Preliminary results show:

Attack of Zymoseptoria tritici varied considerably across the localities in field trial experiments – low attack in UK and Lithuania:

  • Azole mixtures (Osiris and Prosaro) performed most stable across all trials
  • Epoxi performed well in Denmark, Poland, France
  • Met performed well in France and Ireland
  • Prothio performed poorly in France and Ireland, but better in Germany and Denmark
  • Tebu performed relatively well in Belgium and Ireland  and poorly in other trials
  • Some clear links between EC50, mutations and efficacy – but not in all cases!!

General summary about the control effect of Azoles

 Azoles give significant septoria control, excellent rust control and significant yield increases

  • Septoria resistance is evolving at a very different pace across Europe  - major differences in the septoria control profile from azoles
  • Azole performance vary depending on intensity and history of use, EC50 values, CYP51 mutations, but also based on disease pressure and timing
  • Mixtures of azoles give most robust septoria control
  • A clear need to keep a diversity of azoles
  • Data will be made available on