Category: Disease
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Spray Strategies for Strawberry Disease Control in South Carolina

Guido Schnabel, Extension Plant Pathologist Disease management is essential for growing high-quality strawberries in plasticulture. While Botrytis fruit rot (BFR) is a disease you can expect every year, Anthracnose fruit rot (AFR) and the more recently introduced Neopestalotiopsis fruit and crown rot (Neo-P) may or may not appear (Fig. 1). This largely depends on how…
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2025 Recommendations For Fall Chemical Treatments In Strawberry Crops

By Guido Schnabel, Clemson University; Phil Brannen, University of Georgia; Bill Cline and Caleb Bollenbacher, North Carolina State University Whether or not Neopestalotiopsis (Neopest) will harm your strawberries this season depends on many factors – including the quality of the transplants, the cultivar, sanitation practices, soil inoculum levels, weather conditions, and the fungicides you use.…
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Southern Blight is an Unusual Disease on Kale

By Clemson Plant Pathologist Tony Keinath Southern blight is rarely seen on kale or any other brassica crop. In the United States it’s been reported on other brassica vegetables grown in Alabama and Texas. This week, I was surprised to see southern blight causing stem rot just above the soil line on several plants of…
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Reminders about Managing Cucurbit Downy Mildew with Fungicides

From Clemson Plant Pathologist Tony Keinath Cucurbit Downy Mildew This Fall Warm days and cool nights help create long dew periods in the fall, weather is ideal for cucurbit downy mildew (CDM) to start and spread, as reported in the Weekly Field Update – 9/15/25. We have not yet seen CDM in our fall sentinel…
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Why Reusing Watermelon Plastic for Watermelon is a Very Bad Idea and Other Plant Pathology Horror Stories

From Clemson Plant Pathologist Tony Keinath Extension agents have recently received some questions from growers about reusing plastic from a spring watermelon crop for a fall watermelon crop. This scenario is what I call a classic plant pathology “horror story.” It is literally the worst thing a watermelon, cantaloupe, or cucumber grower could do for…
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2025 Recommendations to Manage Powdery Mildew on Cucurbits

From Clemson Plant Pathologist Tony Keinath Results from a June 2025 bioassay with powdery mildew on susceptible yellow summer squash ‘Early Prolific’ showed that, although all 8 fungicides reduced powdery mildew, 4 worked better than the rest. The Best Fungicides To Manage Powdery Mildew on Cucurbits Torino, Quintec, Gatten, and Vivando completely suppressed powdery mildew…
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Weekly Field Update – 7/7/25

After some rain and wind in the Pee Dee from Tropical Storm Chantal on Sunday, the week is off to a hot start. Watermelons, peaches, tomatoes, peppers, etc. are being harvested. Disease and insect pressures are climbing. See details below. Keep an eye on the Upcoming Events tab periodically so you don’t miss any of…
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Weekly Field Update – 6/30/25
Keep an eye on the Upcoming Events tab periodically so you don’t miss any of our winter/spring meetings. Also, check out the latest episode of the SC Grower Exchange Podcast below. Don’t forget to look at our Resources tab for links to crop handbooks, helpful websites, and related blogs. Be sure to scroll all the…
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Gray Leaf Spot on Heirloom Tomatoes

From Clemson Plant Pathologist Tony Keinath Gray leaf spot has been found in a home garden in Greenville County and on a farm in Charleston County, South Carolina. This disease is the most common foliar problem on heirloom tomatoes. ‘Cherokee Purple’ is particularly susceptible. The recent hot, humid, rainy weather is ideal for the gray…
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Biologicals and Their General Performance Against Strawberry Diseases

Johanna Wesche and Guido Schnabel, Clemson University “Do biologicals work?” That is a frequently asked question coming not only from strawberry growers, especially in light of increasing resistance issues with many of the conventional fungicides and the fungicide insensitivity of Neopestalotiopis sp. In our recent article, “Biologicals Made Easy: Grouping and Understanding Biological Fungicides,” we…