The mixture should be agitated to maintain a uniform solution. One 500 gram carton should be mixed with 80 gallons of water. Use 1 gallon of mix per 1-2 tons of potatoes and apply in a fine spray to achieve uniform coverage. Use of more water can increase storage problems. DO NOT use a quaternary ammonium compound since this will leave a residue that will kill the active bacterium.
Plants infected with the disease die prematurely and infected pods produce small discolored seed.
Since this is a food crop the discolored seed destroys the market potential for the crop. The disease is characterized by tan to gray lesions with concentric spore rings inside the lesion that occur on both pods and leaves. At start of the l999 growing season the commonly grown varieties, Sanford and Dwelley, were classified as resistant to the disease. As the season progressed reports from Canada's prairie provinces indicated that this resistance was breaking down. At present, the disease is wide spread and severe in many regions of Canada.