Dickeya species in potato and management strategies

In 2005, Erwinia chrysanthemi was divided in six species inside the genus Dickeya. Until recently, it was thought that only the “cold tolerant” species Dickeya dianthicola (biovar 1 en 7) was present in Europe, causing the disease potato blackleg. Results acquired from a number of seed potato lots in last 5 years showed that a new variant (biovar 3) of Dickeya was isolated and that it did not match any of the described six species of Dickeya. This new variant, tentatively called “Dickeya solani”, was reported in several European countries (e.g. the Netherlands, Poland, Belgium, Finland, France, UK) and Israel. This new variant is also found in flower bulb crops, such as hyacinth and iris. Research was needed to address the following objectives:

- Monitoring (surveys) of Dickeya species in potato with a special emphasis on the new Dickeya-type (“D. solani”)

- Risk assessment (improved understanding of potential risk and impact) also including -aggressiveness -host range -epidemiology

-  Identification and detection tools - new detection and identification tools for the different Dickeya spp.