Breeders in Britain believe they have the tools to stay one step ahead of late blight in potatoes, despite concern about new and more aggressive strains emerging across Europe. Since 2000, researchers have had technology that allows rapid identification of any genetic changes – or new “clones” – in populations of Phytophthora infestans.
Sometimes these clones have little influence on how the disease is managed in the field, but in some instances, they can make life much more difficult for growers. David Cooke and the team at Dundee’s James Hutton Institute, who run the AHDB’s monitoring initiative Fight Against Blight, reported a relatively uneventful year in 2020, as the UK blight population largely remained in status.
However, there were some findings of note, including the fact that previously dominant foe Blue 13_A2 – a clone resistant to fungicide active metalaxyl-M – was largely non-existent and responsible for just one outbreak.
So, what does this mean? Dr Cooke says that when there is a shift in dominant strains, the clones rising to prominence always have a particular characteristic that allows them to gain a foothold. From a British perspective, Dr Cooke says EU_41 is a concern, particularly as the potato industry moves away from intensive fungicide programmes to increased reliance on varietal resistance.
In the Netherlands, Wageningen-based Solynta’s research team lead Michiel de Vries says for blight resistance specifically, institutes like the Hutton and the Sainsbury’s Laboratory have done fundamental work to identify many new resistance genes in wild potato relatives. It is now up to the breeding companies to apply the knowledge by developing resistant varieties.
Source: FWI. Read the full article here
Photo: FWI – courtesy Tim Scrivener