Light Leaf Spot Fungus Affecting Canola and Turnips Confirmed in Oregon

 

On May 1, 2015, USDA’s Animal and Plant Health Inspection Service (APHIS) notified State Plant Regulatory Officials that a light leaf spot fungus, Pyrenopeziza brassicae, was confirmed on July 2, 2014 in canola and turnip plants from a farm in Oregon. Since this first confirmed report, a total of 11 brassica production fields along with various weeds have been found with this pathogen in the Willamette Valley of Oregon.

 

Research scientists consider this disease to be of minor impact. It causes blemishes and discoloration that reduce the market value of vegetable brassicas, although canola is highly susceptible. In addition, climate conditions and timing of plantings in U.S. production regions outside of Oregon may not be conducive to the pathogen’s development.

 

Control of this fungus includes the use of resistant cultivars, weed and debris management, crop rotation, volunteer plant management, and protectant and systemic fungicide applications. Furthermore, seed certification programs and testing may also help manage its spread. For additional information on this pathogen, call Eileen Smith, APHIS National Emergency Response Coordinator at 301-851-2155.