As always, the blight season in 2014 has been different from all others.  Some sites had severe infections in June and others, not more than a mile away, did not suffer infection for another month.  Differences are partly due to microclimate but more likely this year is presence or absence of an active source of infection ie spores being produced from a sprouted and infected tuber that was bought in as seed or was dumped or unharvested from a last year's crop.
Our trial at Henfaes now has dead plots of susceptible varieties (like King Edward and Maris Piper) and growing plots with little or no blight indicating a genotype with substantial resistance.  Simon is scoring the percentage of foliage infected within each plot at regular intervals.  The trial should be demonstrating differences of resistance/susceptibility for all genotypes in time for our Open Days on 4 and 5 September.
Plant pathologist, George Little, from Northern Ireland (Bangor) discussing resistance of clones with Simon in trial at Henfaes.  The King Edward plot has dead foliage