Baseline sensitivity of European Zymoseptoria tritici populations to the complex III respiration inhibitor fenpicoxamid


  • Kildea, S. , Hellin, P. , Heick, T. & Hutton, F. (2022). Baseline sensitivity of European Zymoseptoria tritici populations to the complex III respiration inhibitor fenpicoxamid. Pest Management Science,
Type Journal Article
Year 2022
Title Baseline sensitivity of European Zymoseptoria tritici populations to the complex III respiration inhibitor fenpicoxamid
Journal Pest Management Science
Abstract Background: Fenpicoxamid is a recently developed fungicide belonging to the Quinone inside Inhibitor (QiI) group. This is the first fungicide within this group active against the Zymoseptoria tritici, which causes septoria tritici blotch on wheat. The occurrence of pre-existing resistance mechanisms was monitored, by sensitivity assays and Illumina sequencing, in Z. tritici populations sampled in multiple European countries before the introduction of fenpicoxamid. Results: Although differences in sensitivity to all three fungicides tested (fenpicoxamid, fentin chloride and pyraclostrobin) existed between the isolate collections, no alterations associated with QiI resistance were detected. Amongst the isolates a range in sensitivity to fenpicoxamid was observed (ratio between most sensitive / least sensitive = 53.1), with differences between the most extreme isolates when tested in planta following fenpicoxamid treatment limited. Sensitivity assays using fentin chloride suggest some of the observed differences in fenpicoxamid sensitivity are associated with multi-drug resistance (MDR). Detailed monitoring of the wider European population using Illumina-based partial sequencing of the Z. tritici also only detected the presence of G143A, with differences in frequencies of this alteration observed across the region. Conclusions: This study provides a baseline sensitivity of European Z. tritici populations to fenpicoxamid. Target-site resistance appears to be limited or non-existing in European Z. tritici populations prior to the introduction of fenpicoxamid. Non-target site resistance mechanisms exist, but their impact in the field is predicted to be limited. This article is protected by copyright. All rights reserved.
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Lien https://onlinelibrary.wiley.com/doi/10.1002/ps.7067
Authors Kildea, S., Hellin, P., Heick, T., Hutton, F.