SOUTH CAROLINA: Late blight disease has been reported on tomatoes in Beaufort County.

One of the most destructive and infectious diseases of tomatoes, late blight can cause total loss in tomato crops. The disease has been compared to ‘wildfire’ because of its rapid spread and destruction of the plants it infects. Spread of this disease to other areas of South Carolina is likely if late blight arrived from spores carried from Florida winds. Additionally, with the cool, wet weather South Carolina has experienced this year, this creates a perfect storm for the potential escalation of this disease.

We’ve said before that prevention is key to disease control in tomato fields. To give crops a fighting chance, proactive management will be more important than ever. When checking fields for late blight, look out for these symptoms:

• Large dark-green or gray spots on leaves surrounded by a lighter halo or ring
• Spots are visible on both sides of the leaves
• White-to-gray fungus growth development on the undersides of the leaves at the edges of the spots
• Dark brown spots on the stems and petioles
• Tomato fruit rot (blotchy and dark brown, but firm)

Clemson Cooperative Extension recommends that all growers carefully check tomato crops and — if the disease is discovered — treat them immediately. Growers along the coast should preemptively treat regardless.

For effective control, Syngenta recommends Orondis Opti® fungicide in a season-long disease management program with other fungicides like Revus Top^®. Orondis^® Opti fungicide exhibits exceptional long-lasting disease control and systemic redistribution, bringing best-in-class protection against late blight in tomatoes. Combining the proven multi-site action of chlorothalonil, with the unique mode of action of oxathiapiprolin, Orondis Opti also offers built-in resistance management and can be included in a season-long disease control program.  To find out if Orondis Opti is approved for use in your area, visit this page.

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