As the season begins to wind down for many organic farmers in New Jersey and the rest of the mid-Atlantic region, the question now becomes where to get potato seed for next year? Using PCR testing and North American Certified Seed Potato Health Certificates to track lot numbers, 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’, ‘Atlantic’, and ‘Chieftain’. A few of these varieties (Yukon Gold, Kennebec, and Chieftain) are grown organically in New Jersey and are bought through growers/distributors in Maine as well as other States.
Organic potato growers in New Jersey (and the region) who are currently looking for sources of seed for next season need to do their own due diligence and avoid those varieties and operations which have proven to be a source of Dickeya. Importantly, organic growers need to pay close attention and ask where their seed originated and for the accompanying North American Seed Health Certificate. This certificate will tell you where the seed was produced and by whom. As a note, organic seed suppliers who do not produce their own seed can purchase and re-sell seed from other seed growers. This seed may be organically or conventionally produced depending on whether there is a source of organic seed available or not. Checking the Production Environment Pedigree on North American Seed Health Certificate to know where the lot was grown in previous years and/or originated may also provide valuable information for potential Dickeya infestation since most of the seed bought in the region is year FY4 or FY5. Remember, a North American Seed Health Certificate with a 0% Blackleg reading does not mean the seed lot is necessarily free of Dickeya. The only way to know is to have the lot tested specifically for the pathogen using PCR and/or to cross check that lot with other seed from the same lot that may have or may not have been tested and sold to others. Organic potato growers need to follow the same best management practices as conventional growers.
The best method for keeping your potato operation Dickeya-free is to adopt your own 0% Dickeya-tolerance policy.
