Kate Everts, Vegetable Pathologist, University of Delaware and University of Maryland; keverts@umd.edu
Basil downy mildew has been reported in two locations in Maryland this week. It was confirmed in Ellicott City, and we received a separate report in Calvert County. Growers should check their plants carefully for disease symptoms. Products that are labeled for Basil Downy mildew are Pro-Phyt, Fosphite, K-Phite, and Quadris. These products have some efficacy on this disease in trials.
Downy mildew infected basil: lower leaf sporulation and yellowing on the upper leaf surfaces