Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu
Downy mildew on cucumbers was found in another field of commercial cucumbers in Columbus County in southeastern NC this week. Downy mildew was also observed for the first time in sentinel plots in SC and AL. Yesterday on Thursday, June 18 there was a moderately strong risk of transport of spores for Delaware and the eastern shore from Clarendon County, NC (see map). Growers and processors are encouraged to keep abreast of the progress of downy mildew by visiting the CDM ipmPIPE website http://cdm.ipmpipe.org. Forecasts are made every Monday, Wednesday and Friday. With the weather pattern favoring diseases this year a cover spray of Bravo or mancozeb on cucumbers at this point should be considered. Once the disease gets closer or is found in DE then switching to a downy mildew specific fungicide such as Previcur Flex, Presidio, Ranman or Tanos would be recommended.
