Andy Wyenandt

Cucurbit downy mildew has been confirmed on cucumber in Hunterdon County in Northern New Jersey. Downy mildew was found in cucumber in the southern part of the state a few weeks ago. To date, cucurbit downy mildew has only been reported in cucumber in the mid-Atlantic region. All cucumber growers who have not included a downy mildew-specific fungicide in their weekly spray program should do so. For more in formation on controlling cucurbit downy mildew please see the 2016 Mid-Atlantic Commercial Vegetable Production Recommendations Guide.

• Asparagus rust has been reported. All growers with nursery, 1-, or 2 yr-old plantings should scout regularly and apply a protectant fungicide if one hasn’t initiated fungicide program to date.
• Bacterial leaf spot in pepper has been reported in southern New Jersey.
• Cucurbit downy mildew has been confirmed on cucumber in New Jersey. All cucurbit growers need to scout on a regular basis. All cucumber growers need to add a downy mildew-specific fungicide to their weekly fungicide programs. There have been no reports of downy mildew in other cucurbit crops in New Jersey to date.
• Reports of Dickeya dianthicola in additional potato varieties continue across the east coast. Dickeya dianthicola has been confirmed in 11 states to date on potato seed originating from Maine and New Brunswick, Canada this growing season. All potato growers are encouraged to scout fields and report any suspect plants/tubers. The best method for keeping your potato operation Dickeya-free is to adopt your own 0% Dickeya-tolerance policy.

Dickeya dianthicola has been reported in potato in Rhode Island this summer. This makes it the 11th state this summer to report the pathogen in potato. The pathogen has also been detected in NJ, MA, DE, PA, MD, VA, NC, WV, and FL this year. All potato growers, crop consultants, scouts, industry representatives, and Extension personnel in states which grow potatoes should remain vigilant by scouting their fields for Dickeya symptoms on a regular basis and by submitting any suspect samples for diagnostic testing. Additionally, in recent days and weeks there has been a lot of misinformation circulating (both written and in person) about the pathogen – Dickeya, its biology, potential sources of the inoculum, and much more. All potato growers when deciding on where and from whom to buy their seed from next year need to do their own due diligence, talk with other growers [(especially those who have had the unfortunate experience with Dickeya and have received infested lot(s)] and to speak with their local Extension Service to find out the facts to help them make the appropriate decisions to avoid problems. The best method for keeping Dickeya off of your potato farm and to avoid potential loses is to adopt your own zero-tolerance policy for the disease.

For more information on Dickeya please see the following articles posted online – source(s) of information:

Dickeya: A new potato disease – Growing Produce

Blackleg is Once Again Being Observed in Potato Fields Across the Mid-Atlantic Region – Penn State University

Update on Dickeya detections in potato – University of Delaware

Dickeya Blackleg: New potato disease causing major impact. – Cornell University

Watch for Dickeya – a new potato disease – The Ohio State University

High security Aroostook farm advances tater technology. – Maine Potato Board

Slowing Dickeya, other pathogens in Canada. – North Dakota State University

Dickeya: A new threat to potato production in North America. – SPUDsmart

Dickeya is coming. – University of Wisconsin/North Dakota State University

Maine ‘Ground Zero’ for new potato disease. – Maine Department of Ag.

Maine seed potato growers looking to protect brand against disease. Maine Department of Ag./Maine

Dr. Meg McGrath, vegetable pathologist with Cornell University on Long Island has published her 2016 cucurbit powdery mildew control report. The report contains useful information for conventional and organic growers. Please click here to see report. For more information on controlling cucurbit powdery mildew, please see the 2016 Mid-Atlantic Commercial Vegetable Recommendations Guide.