When it comes to treating diseases in cucurbits in the Southeast, the early bird gets the worm. And fortunately, the most damaging diseases have several effective chemical treatment options available. When chosen and applied promptly and aggressively, multiple fungicides can help delay any mode of action resistance and enrich both cucurbit crop yield and quality.

Hot, dry conditions this spring limited disease development with the first crop plantings. Now that more seasonal, humid weather has moved in, the disease outlook has changed. Watermelon has been hit with gummy stem blight and both watermelon and squash are experiencing more downy mildew. Downy mildew moved up quickly from FL to gain traction in the Southeast.

Sustainable gummy stem blight control requires a constant rotation of active ingredients. The products listed below allow you to switch modes of action and delay resistance development:

• Inspire Super® fungicide combines difenoconazole and cyprodinil to help manage potential resistance. Inspire Super fits easily into disease control programs, offering not only excellent rainfastness, but also flexible application to optimize yield and quality.
• Miravis® Prime fungicide is a preventive and curative fungicide, containing Adepidyn® technology (pydiflumetofen) and fludioxonil. Miravis Prime’s active ingredients work well into integrated spray programs for gummy stem blight as well as downy mildew.
• Aprovia® Top fungicide offers excellent preventive activity and broad-spectrum disease control in cucurbits. Known as a versatile tank mix, it contains difenoconazole and benzovindiflupyr and is useful in rotation programs with other modes of action.

Downy mildew control also can be achieved using multiple products incorporated into an active ingredient rotation. Current disease information from Clemson University Extension and the Cucurbit Downy Mildew Forecast are both instrumental in making product selections.

Orondis® Opti fungicide is a good fungicide for curtailing downy mildew, as the chlorothalonil and oxathiapiprolin fungicide pre-mix provides multiple modes of action. Oxathiapiprolin helps protect developing leaves and has no cross resistance to other fungicides, making it a good partner in a disease control program.

Other diseases could blow up in cucurbits this summer and fall as subsequent plantings occur. Actigard® Plant Activator fungicide is a good addition to boost your disease control program by helping plants protect themselves. Actigard is highly effective at low use rates and partners well when aggressively managing Alternaria, anthracnose and powdery mildew later in the season.

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Product performance assumes disease presence.

Performance assessments are based upon results or analysis of public information, field observations and/or internal Syngenta evaluations. Trials reflect treatment rates commonly recommended in the marketplace.