The late blight strain found July 2  in a Port Burwell, Ontario potato field is likely to be US 23, the tomato strain. A sample will be sent to A & L Laboratories to conduct a PCR test for identification. 

“The field is of a variety very susceptible to late blight,” reports Eugenia Banks, PhD, Ontario Potato Board researcher and potato specialist. “The grower is taking the appropriate measures to avoid the spread of this disease.  According to the very competent scout, there was a spot with only five plants infected.” 

Orondis plus MZ or Bravo and Copper will be sprayed at the farm shortly.

Banks advises growers to spray late blight protectant fungicides. 

Source:  Ontario Potato Board July 2, 2024