,
 

Diseases of Potatoes: Brown Rot

 
 
Subscribe to our free E-Newsletter, "RTW This Week"Sign up for our
E-Newsletter
  
 
 
 What's the flap about Brown Rot of potatoes?
This is a destructive bacterial rot disease of potatoes that is widespread in the rest of the world except for North America. This is a quarantinable disease just like Potato Cyst Nematodes (2 kinds) and Potato Wart. The brown rot bacterium is classified as Ralstonia solonacearum (Pseudomonas solonacearum). This brown rot bacteria exists in many race types, i.e. Race 1, 2, 3, 4 and 5 and each race has what we refer to as specific biovars (i.e. biological variants). This brown rot bacterium and its biovars can attack over 200 plant species in 50 families - a very broad host range.

In nature, in one of the dozens of countries where this disease exists, potatoes are attacked by Race 1 (biovars 1, 3 and 4) and Race 3 (biovar 2). Race 1 and it's biovars is subtropical (biovars 1, 3 and 4) and will not survive in Canada. Race 3 biovar 2 is typically found on potatoes but it can also infect Pelargonium (geranium) eggplant, tomato and pepper. Race 3 widespread in tropical countries can apparently overwinter in Europe where it is a quarantinable pest. It is at present only suspected that this disease can overwinter in Canada, none-the-less, CFIA (Canadian Food Inspection Agency) is not taking any chances. The CFIA is now going to take a much closer look at the import of plant materials particularly in the more urban areas of Quebec, Ontario and British Columbia where milder climates and more host plants are grown such as peppers, tomatoes and other ornament hosts.

No need to panic over this bacterial disease since it was picked up and eliminated in a few sites in Eastern Canada and the United States. None-the-less it's one more disease of potatoes that we should be aware of in Alberta.

Information assembled and prepared for ARD by Dr. Ieaun R. Evans Agri-Trend Agrology Ltd.		  
 
 
 
For more information about the content of this document, contact Ron Howard.
This document is maintained by Shelley Barkley.
This information published to the web on January 2, 2004.
Last Reviewed/Revised on March 18, 2008.