The overall objective of the EuroBlight workshop was “to present and discuss recent results on integrated control of late blight (Phytophthora infestans ) and early blight (Alternaria spp.).”

To achieve this, sessions were devoted to the importance and characteristics of late and early pathogens, the status in Europe and beyond (including updates from the Asian and Latin American monitoring networks), epidemiology and host resistance, and control strategies (including an update on precision agriculture in potato cropping, a systems approach for early warning and control in Denmark and intercropping as a sustainable alternative to reduce late blight infection in potato).

In addition, separate subgroup discussions were held. These were dedicated to control strategies, pathogen characteristics and host resistance, and Alternaria . Most of the presentations are now available online from the EuroBlight website (see link below).

The results of EuroBlight’s potato late blight monitoring in 2021 are also available on its website. Almost 2,500 samples from 26 countries were genotyped last year, bringing the total of samples to around 15,000 since the programme was launched in 2013.

It reports the key findings:

• The blight pressure in 2021 was higher than average across many parts of Europe.
• Disease outbreaks from 26 countries were sampled by several groups in 2021 resulting in 2,492 genotyped samples.
• Around 72% of these samples were of defined clonal lineages observed in previous seasons while the rest consisted of ephemeral, genetically diverse ‘Other’ types consistent with oospore-borne inoculum.
• The proportions of the main clones in the 2021 population were broadly similar to those reported in 2020. Newer clones  EU_41_A2,  EU_37_A2, EU_36_A2, EU_43_A1, EU_44_A2 and EU_45_A2 made up 48% of the 2021 population. These clones are displacing the established 13_A2, 6_A1 and 1_A1 clones which caused only 17% of the blight lesions sampled in 2021.
• Regional trends in the type and proportion of clones compared to sexual recombinant populations were observed across Europe. For example, ‘Other’ genotypes more prevalent in Denmark, Norway, Sweden and Finland than across countries to the west of Europe.

For more information:

• Explore the workshop presentations on the EuroBlight website here
• Read more about the 2021 sampling results on the EuroBlight website here