Photos 1, 2. Early symptoms of downy mildew on cucumber with the yellow-brown tissue bordered by the leaf veins. Photos 3, 4. The dark spores of the cucumber downy mildew pathogen can be seen on the underside of the leaf. These spores move via air currents and infect unprotected plants. Photos by David Perla, MSU.
Clade 2 of the cucurbit downy mildew pathogen spores have been verified in air samples from the east side of Michigan in a region that hosts vegetable production for the fresh and processing markets. The positive air samples are the first confirmation of airborne downy mildew sporangia for the state of Michigan this year. Clade 2 of the cucurbit downy mildew pathogen spores can infect cucumber and melon. A cucurbit downy mildew disease outbreak on cucurbits has not been reported in Michigan at this time. Visit the Hausbeck lab’s spore trap webpage for the latest updates.
