Dr David Cooke delivers key findings on the Fight Against Blight Project at British Potato 2023
- Despite severe blight pressure and detailed sampling (thanks to scouts) the GB population of P. infestans was shown to be dominated by EU36 and EU6 with NO sampling of the EU43 lineage that has reported CAA resistance
- No issues detected in the fungicide sensitivity assays Hutton ran on the GB FAB isolates against the 5 actives chosen by sponsors (ametoctradin, amisulbron, oxathiapiprolin, propamocarb and zoxamide). Included in the testing were 5 strains of EU43 and EU41 from DK in 2022 which were also sensitive to the same 5 actives.
- A bullet on oxathiapiprolin resistance was added to in light of information recently announced by Corteva. Resistance has been reported in a defined area of continental Europe. Testing by FAB and Corteva has found no such resistance in the UK but Corteva will be proactive in providing updated advice on best practice use for 2024.
- A single sample of EU43 was found from an FTA card in a TEAGSAC trial in Ireland (Carlow) and is under investigation by Steven Kildea. Steven Kildea has given permission for this to be mentioned.
- The full Euroblight report is currently being drafted but Geert Kessel at WUR has given permission to state there have been challenges with blight control in The Netherlands in 2023 due to the issues with mandipropamid and oxathiapiprolin resistance. Lessons are being learned and it is clear that the 2024 fungicide programmes need careful consideration. We recommend that FAB monitoring continues into 2024 to keep GB growers up to date and inform the industry on effective blight control.
The GB data will be reported in the context of the wider Euroblight monitoring data which the consortium also propose to release in November. We are busy at Hutton processing the many samples at the moment.