It’s that time of year again. Cucurbit downy mildew is on the move and the extension pathologists involved in the Cucurbit Downy Mildew ipmPIPE project had our first conference call this morning. To date outbreaks of downy mildew have been reported on a variety of cucurbits in Florida, south Georgia, eastern North Carolina and south Texas. To track current and future outbreaks, see http://cdm.ipmpipe.org/. So far I have not had any reports of downy mildew on cucurbits in Louisiana, but county agents and growers should be on the alert as we generally first see the disease show up toward the latter part of June. Although the pathogen doesn’t attack the fruit, it can cause severe defoliation exposing the fruit to sunburn. If we get into a period of rainfall like we had a week or two ago, the disease could develop rapidly. With this in mind, it might be advisable to have growers begin applying preventative fungicide sprays on a regular basis now. For information on the efficacy of fungicides registered for the control of cucurbit downy mildew, see page 194 of the 2010 Southeastern US Vegetable Crop Handbook at http://tinyurl.com/2uph75e. For photographs and more information on cucurbit downy mildew, see the Louisiana Plant Pathology fact sheet at http://tinyurl.com/3xapmrd.