Recent weather has been conducive to the development and spread of late blight. Commercial growers should scout often and ensure they are using fungicides with good late blight activity in their fungicide program. When late blight is in the area, spray intervals should be shortened.
Contact OMAFRA at 519-674-1690 or firstname.lastname@example.org if you suspect you have found late blight on tomato in Ontario.
Identifications of late blight genotypes for Ontario are provided by L. Kawchuk, AAFC Lethbridge, Alberta, Canada.