The Factsheet: Cucurbit Downy Mildew in Kentucky (PPFS-VG-27) is available online. For additional publications on vegetable diseases, visit the UK Plant Pathology Extension Publications webpage.
Author: cuccap
CDM confirmed in Central Kentucky
On August 9, 2024 cucurbit downy mildew was confirmed on cucumber in south-central Kentucky. Cucurbit downy mildew has also been reported in neighboring states. Disease is expected to become widespread across the area.
Downy mildew confirmed on cucumber in western NC
Water-soaked lesions on the undersides of leaves were observed with signs of the pathogen — gray to black spores on the underside of the leaf. Very light yellow spots or lesions were observed on the upper sides of leaves. At the moment, downy mildew has not been observed on any other cucurbit in western NC.
Downy mildew and Phytophthora threaten Michigan Cucurbits
Cucurbit crops, excluding pumpkins, are being harvested, with vigilance against downy mildew and Phytophthora pathogens. Downy mildew has been confirmed in 13 Michigan counties, affecting cucumber and melon crops. Phytophthora symptoms are expected to increase following recent rains, impacting plant crowns and fruit.
Whitefly Damage on Cucurbit leaves
Unique silvering of the leaves is the characteristic symptom induced by feeding of immature stages of silver leaf whitefly which releases a toxin inducing the unique pattern on the leaves.
South Carolina Grower Update | August 12, 2024
As our late-summer and fall plantings get underway, keep in mind two cucurbit insect pests that worsen around this time: whiteflies and caterpillars.
South Carolina Grower Update | August 5, 2024
Winds and rain from Hurricane Debby may bring fungal spores or bacterial cells into fields in South Carolina. Before the rain starts, cucumber, cantaloupe, pumpkin, and watermelon crops should be sprayed with a fungicide to protect them from downy mildew
ONvegetables VCR | August 1, 2024
Phytophthora infections are being reported in watermelon, pumpkin and squash across the SW Ontario growing region. Once established in a field, there are no effective treatments that will control the spread. If the infection is limited to an isolated area, and has not begun to spread, destroying the infected plant may prevent further spread.
