Downy mildew of cucumber.
Downy mildew was confirmed today in Saginaw County, MI. Dr. Mary Hausbeck’s team at Michigan State University also detected spores of the downy mildew pathogen, Pseudoperonospora cubensis, in air samples in several MI counties. Although we haven’t seen or heard of downy mildew on cucumbers yet this year in Ohio, it is likely already here or soon will be. Cucumber and melon growers in northern Ohio should start adding fungicides very effective against downy mildew to their spray programs now. These are Orondis Opti, Ranman, Omega, Previcur Flex, and Elumin. More information on these fungicides can be found here.