Island growers should be on the lookout for early blight, and should be considering applying preventative fungicides for early blight right now, as weather conditions are prime for early blight spread. In addition, a number of growers with spore collectors have been finding spikes in early blight spores this week…so time to pay attention to early blight now! Regular contact fungicides (manzoceb, chlorothanonil) are often not sufficient in controlling early blight. Consult the PEI Crop Protection Guide for a list of fungicides registered for early blight.
In addition, if you find foliar symptoms of early blight, please consider taking some leaf samples and providing them to either the PEI Plant Pathology Lab (Marleen Clark) or Ryan Barrett. The Board and AAFC are cooperating on an early blight fungicide resistance project this year, to assess whether registered fungicides are effective at controlling early blight in PEI. Samples should be placed in a ziploc bag with a moist paper towel and refrigerated until you can get to either Marleen, Ryan, or any member of the PEI Dept of Ag staff.
For a factsheet on identifying and controlling early blight, click here.