Investigation of Erwinia chrysanthemi (Dickeya dianthicola and other Dickeya spp.) able to infect potatoes

Summary

At the time the research was commissioned there was increasing concern about the threat posed by bacterial pathogens, particularly their impact on seed production. The pathogen Erwinia chrysanthemi had been reclassified into 6 species of the genus Dickeya and more information was needed on their distribution. The different methods available for detecting and quantifying the bacteria were compared to determine if they are all suitable for the detection of all Dickeya species that can infect potato. Samples collected from water courses were tested for the bacteria.

Results

  • A collection of 219 Dickeya isolates were identified to species and their distribution was mapped by continent and by country in Europe
  • All isolates of Dickeya found on potato entering, or grown in, England and Wales were identified as D. dianthicola
  • The frequency of occurrence on home-grown potatoes was found to be low (around 1%) in 2007. Permission was not obtained to test imported potatoes
  • Dickeya species were detected sporadically in 35% of watercourses sampled in England and Wales in September 2007
  • No evidence was found that Dickeya species had infected riparian weeds in the rivers in which it was detected 
  • D. dianthicola was found to infect Solanum dulcamara under glasshouse conditions and has been reported to infect the plant under natural conditions in Sweden
  • A modified selective medium (CVPM) allowed isolation of all Dickeya species.  A real-time PCR assay allowed detection and identification of all Dickeya species  but insufficient 16S rRNA and recA gene sequence variation was found for the development of specific assays for individual detection and identification of the different Dickeya species.
Sector:
Potatoes
Project code:
R290
Date:
01 April 2007 - 31 May 2008
AHDB sector cost:
£33,160
Total project value:
£33,160
Project leader:
John Elphinstone

Downloads

20087 Dickeya Final Report R290_0

About this project

To compare the different methods available for detection and quantification, to determine whether they are suitable for the detection of all Dickeya species that can infect potato.

×