Cucurbit Downy Mildew Diagnosed in Cheatham Co.
This past week, Cheatham County became the 4th county in the state to positively identify Downy Mildew. The disease was found on a commercial pumpkin planting. Downy Mildew can be blown in by wind currents and can overwinter on live hosts (weeds etc.) if environmental conditions are favorable. Spore development is favored by high temperatures and high humidity (we have had both). This disease can affect home grown cucurbits as well as commercially grown crops. Some of the things we can do to prevent, contain or at least slow down the spread are as follows:
· Prevent overhead watering
· Pull up and destroy plants (that have been positively identified with the pathogen)
· Plant tolerant varieties
· Apply fungicides for control (Chlorothalonil and Mancozeb products are pretty much the only homeowner options. Fixed-copper is organic and can give fair control). For commercial growers and homeowners alike, see the attached publications for control options
If you suspect this disease on your farm or in your garden, please bring us a sample to the UT/TSU Extension office or send us high quality photos by e-mail (both sides of the infected leaf).