Using PCR test results and North American Certified Seed Potato Health Certificates to track Lot no., Dickeya dianthicola has been reported in 16 states (DE, FL, MD, MA, NJ, NY, NC, PA, RI, VA, WV, OH, IN, MO, MI, and TX) on at least nine potato varieties to date in 2016. These varieties include: ‘Reba’, ‘Superior’, ‘Vivaldi’, ‘Norwis’, ‘Snowden’, ‘Yukon Gold’, ‘Beacon Chipper’, ‘Kennebec’, and ‘Atlantic’. Known sources of infested seed found in potato fields on the East Coast have originated from at least two suppliers in Canada and a number of seed suppliers in Maine this past growing season. To better understand the scope and breadth of the pathogen affecting potato production on the East Coast, information on known varieties and lot numbers that tested positive for Dickeya this past summer have been collected. This information is now available. It’s important for potato growers using this information to know that this list is a working document and not all Dickeya dianthicola test results are known or have been made public or available by the Maine Potato Board or the Maine Department of Agriculture (or Canada). Dickeya testing is being done in Maine by the Maine Potato Board/Maine Department of Agriculture and independently by the University of Maine and other Universities and laboratories. Potato growers with any questions or concerns about Dickeya-infested varieties and seed lots in 2016 and sources of seed for 2017 should contact the Maine Department of Agriculture; or Potatoes New Brunswick, if purchasing seed from these regions.
Dickeya dianthicola has been detected in the US in the past, and because of this, APHIS has designated the pathogen as a non-reportable/non-actionable pathogen despite its potential to cause 100% crop loss. A link to best management practices for managing Dickeya dianthicola in the Northeast (and mid-Atlantic region) can be found here. Importantly, there is no current policy in place designed specifically for regulating and/or controlling Dickeya dianthicola in seed potato coming into the US from Canada. The Maine Potato Board’s Executive Seed Council adopted their own Blackleg-tolerance policy last winter which is followed by the Maine Department of Agriculture. For more information on this policy please contact the Maine Potato Board or the Maine Department of Agriculture.
The best method for keeping your potato operation Dickeya-free is to adopt your own 0% Dickeya-tolerance policy.