Scout Emerging Potato Fields for Seed-Born Late Blight Infections

Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu

There have been several reports of late blight from Florida. The most recent was a report from north Florida in the Hastings area that was identified early, fungicides were applied and the situation is under control. This is a reminder that there was late blight in many of the seed producing areas last season. In spite of all the precautions and seed testing that occurs to reduce the chance of seed tuber infections, infections can occur if the weather is right and the seed is infected. Be sure to be checking fields as they emerge for any seed born infections. Apply fungicide sprays of mancozeb or chlorothalonil once the plants begin to touch down the row. There is a late blight monitoring website http://usablight.org/ that you can use to see what is happening around the country with late blight on tomato and potato.