Cucurbit downy mildew is on the rise in parts of Florida, according to the South Florida Pest and Disease Hotline.
Gary Vallad, University of Florida Institute of Food and Agricultural Sciences Gulf Coast Research and Education Center plant pathologist, and Lisa Hickey, UF/IFAS Extension agent, are reporting increased infestations in cucumber and squash fields in central Florida. They have gone from low to moderate levels.
Recent rains have helped downy mildew infestations to increase in melons in Southwest Florida.
Downy mildew is found annually on squash, cucumbers, pumpkins, muskmelons and other cucurbits in Florida. The disease is an annual problem on watermelons in South Florida. It will reduce yields, fruit quality and harvesting time. It causes leaf infections that impair the photosynthesis in the plant.
Resistant varieties and/or a fungicide spray program are recommended management tools. Spray programs are the most impactful when implemented prior to the first sign of the disease.