Tuesday, 3 September 2019
Growers have seen mixed fortunes in the weather this August, which has been keeping scouts and the blight team at the James Hutton Institute very busy.
A sustained period of wet weather in Scotland has triggered challenging conditions, with a high number of samples sent into the Hutton despite the use of some robust spray programmes.
Large parts of England and Wales have also seen high blight pressure and scouts have been doing a great job sending in samples from around the country.
Dr David Cooke, Research Lead at the Hutton for AHDB’s Fight Against Blight, said: “As of 30 August we’ve received samples from almost 200 outbreaks, and as the conditions remain favourable for blight, we have more arriving every day.
“To date we’ve genotyped 470 samples.
“The real-time genotyping that is being conducted this year has allowed scouts to gain a picture of the pattern of P. infestans clones across GB crops during the season, and has captured the appearance of 36_A2 in three outbreaks in Scotland. “
The genotype frequency across all regions can be found by logging in to the Fight Against Blight website.
Fight Against Blight website
AHDB would like to take this opportunity to thank our blight scouts for their patience.
After some technical issues with the Fight Against Blight website this season, the website is now fully operational and scouts can submit samples and access their genotype results as required.
So far, almost 20% of the genotyped samples across GB crops are of the 36_A2 type but the frequency is greater than 40% in England.
The east of England has seen 70 samples identified as 36_A2, whereas samples from the East Midlands and Cheshire, have only resulted in three and five positive samples of 36_A2 respectively.
After a drier July led to fewer blight outbreaks in some parts of the country, a wet August has seen an increase in blight in crops.
In order to get a better picture of the genotypes appearing in the East Midlands and Yorkshire regions, we encourage Scouts to send in FTA card samples from those areas. FTA cards are included in all scout packs, packs can requested through the Fight Against Blight Website: click here to order a scout pack.
At 8%, the overall frequency of the fluazinam insensitive strain 37_A2 appears to be dropping this season, compared to 2018. Its geographical range is still roughly the same as last year; being found across Wales, the Midlands, East Anglia and further north into Yorkshire and Cheshire, with just one sample so far in Scotland.
Fungicide sensitivity testing is being undertaken as part of Fight Against Blight this year, and the team at the James Hutton Institute, led by Dr Alison Lees, are in the process of testing isolates collected this season belonging to a range of genotypes including 36_A2, 37_A2 and 6_A1.
The genotype and fungicide sensitivity testing results will be presented at the Agronomists Conference in December, you can find a full agenda and details on how to register by visiting our Agronomists' Conference event page.