Over the last two potato growing seasons late blight management has been under severe pressure across much of Europe. The cause? A combination of very wet weather and clones of Phytophthora infestans, the potato blight pathogen, that have evolved resistance to two key fungicide active ingredients.
The UK industry-sponsored Fight Against Blight (FAB) campaign has thus been more important than ever. Late in 2024 one of these problematic clones, named EU46, with resistance to oxathiapiprolin, was detected in crops in south west Wales and eastern Scotland. Its sister clone, EU43, in which double resistance to oxathiapiprolin and mandipropamid has been reported, is prevalent in continental Europe but fortunately has yet to be sampled in UK crops.
Against this backdrop, The James Hutton Institute was pleased to launch the 2025 FAB programme with a new, clearer and simpler web-page for PC and mobile phone outbreak reporting, thanks to funding secured through GB Potatoes plus that from another 16 key sponsors listed below.
Crucially, 150 volunteer 'scouts' from across the industry have signed up to be FAB's 'eyes and ears', keeping a look out for late blight in crops, potato dumps or volunteer plants in other crops.
After a warm and dry spell across much of Britain, late blight risk levels and reported outbreaks are well below average for July - we had 150 outbreaks by this date in 2024. Nonetheless, 14 outbreaks have now been reported and nine have been genotyped. Of particular concern are three outbreaks in Wales caused by the EU46 clone of P. infestans, which will have an impact on local fungicide choices for the remaining part of the season. The other outbreaks have been caused by familiar EU36 and EU6 clones with one outbreak in Scotland the result of diverse 'Other' genotypes.
Growers and agronomists are encouraged to be aware of the current increased risks as the pathogen is active and the weather forecast unsettled in several potato growing areas. See https://blight.hutton.ac.uk/ for details.
BlightSpy provides a blight risk forecast and data on current and forecast weather conditions conducive to late blight. Hutton BlightSpy
We thank James Hutton Scientific Services for their continued support of BlightSply and the sponsors of FAB 2025.
GB Potatoes, Certis Belchim, UPL, BASF, Bayer, Corteva, Syngenta, Albert Bartlett, FMC, Pepsico, Agrovista, Frontier, Hutchinsons, McCain, Scottish Agronomy, ProCam, SAC, Agrico, Branston, Agrii
Blog by David Cooke
