Survey of the bacteria causing blackleg in English and Welsh seed potato crops (2010-2015)

• R437 [2010, £20,000]
• R454 [2011-2012, £40,000]
• R491 [2013-2014, £40,000]
• 1100016 [2015, £22,000]

Each year, samples of infected plants were collected by Plant Health Seed Inspectors (PHSI) during classification inspections and sent to Fera for diagnosis. The initial focus of the work was to understand the incidence and distribution of Dickeya solani  and D. dianthicola in UK-grown seed.

Additional work was subsequently included to help understand the sources of contamination of pre-basic seed crops with Pectobacterium atrosepticum (Pba). This involved the use of a strain typing (VNTR) method in which DNA analysis was used to compare the Pba isolates collected from blackleg plants and their progeny tubers with the isolates in the surrounding environment and on associated machinery. The results are discussed in more detail in the final report for the related research project 

Results

• 2010 Pba was the cause of blackleg in 75.2% of affected seed stocks
• 2011 Pba was the cause of blackleg in 74.4% of affected seed stocks
• 2012 Pba was the cause of blackleg in 84.1% of affected seed stocks
• 2013 Pba was the cause of blackleg in 86.5% of affected seed stocks
• 2014 Pba was the cause of blackleg in 93.6% of affected seed stocks
• 2015 Pba was the cause of blackleg in 89.4% of affected seed stocks.