Andy Wyenandt

This is an archive of Dr. Wyenandt's posts on the Plant and Pest Advisory.

Dickeya dianthicola affecting potato growers throughout Mid-Atlantic region and elsewhere – Updated 7/11/16

In addition to Dickeya dianthicola being found in ‘Superior’, ‘Reba’, ‘Snowden’, and ‘Norwis’ on 3 farms in New Jersey this year, the pathogen has also been detected in fields with seed originating from Maine on 5 farms on Long Island in ‘Reba’, ‘Vivialdi’, ‘Superior’, ‘Norwis’, and ‘Waneta’. Other varieties such as ‘Yukon Gold’ have also tested positive for Dickeya. The pathogen has been detected in MA, DE, PA, MD, VA, NC, WV, and FL this summer on seed from Maine and New Brunswick, Canada (NJ and VA). Maine potatoes are currently shipped to over 20 states across the country (CA, CT, DE, FL, ID, IN, KY, MD, MA, MS, NH, NJ, NY, NC, OH, PA, RI, TN, VT, VA, WA, WV, and WI). Potato growers, crop consultants, and Extension personnel in states which grow Maine potatoes should remain vigilant by scouting their fields for Dickeya symptoms on a regular basis and by submitting any suspect samples for diagnostic testing. Dickeya dianthicola has been detected in the US in the past, and because of this, APHIS just recently announced that the pathogen has been designated as a non-reportable/non-actionable pathogen despite its potential to cause 100% crop loss. A link to the USDA/APHIS website for information on Dickeya dianthicola detection and control can be found here.

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

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 Potato Board

Vegetable Disease Briefs – 6/30/16

  • Basil downy mildew has been confirmed in southern and central New Jersey.
  • Cucurbit downy mildew has been confirmed as far north as Maryland this week.
  • Bacterial canker in tomato has been reported.
  • Angular leaf spot of cucumber has been reported. Water-soaked lesions similar to cucurbit downy mildew appear on the bottom of the leaves at first. In the case of angular leaf spot, caused by a bacterium, no spores will develop on the underside of leaves.
  • Reports and sampling for Dickeya dianthicola  in potato across the east coast continue.

Basil downy mildew confirmed in southern and central New Jersey – ALERT 6/30/16

Basil downy mildew has been confirmed on field-grown basil in southern and central New Jersey on 6/29/16. This is the first report of the pathogen in New Jersey and the mid-Atlantic region this growing season. All basil growers are encouraged to scout on a regular basis and initiate a protectant fungicide program if one hasn’t been started.

Cucurbit downy mildew confirmed on cucumber in Maryland – ALERT

Cucurbit downy mildew was confirmed on cucumber in Caroline County, Maryland on the Eastern Shore on 6/27. This is the first report of cucurbit downy mildew in the mid-Atlantic region this growing season. All cucurbit growers should scout their fields on a regular basis and initiate a protectant fungicide program. Cucumber growers should include downy mildew-specific fungicide(s) in their weekly applications. For more control information on the control of cucurbit downy mildew please see the 2016 Mid-Atlantic Commercial Vegetable Production Recommendations Guide.

Dickeya dianthicola affecting potato growers throughout Mid-Atlantic region – Updated 7/5/16

In addition to Dickeya dianthicola being found in ‘Reba’, ‘Snowden’, and ‘Norwis’ on 3 farms in New Jersey this year, the pathogen has also been detected in fields with seed originating from Maine on 5 farms on Long Island in ‘Reba’, ‘Vivialdi’, ‘Superior’, ‘Norwis’, and ‘Waneta’ and three fields of ‘Vivaldi’ in DE. The pathogen has been detected in PA, MD, VA, NC, WV, and FL this summer on seed from Maine and New Brunswick, Canada (NJ and VA). Maine potatoes are currently shipped to over 20 states across the country (CA, CT, FL, ID, IN, KY, MD, MA, MS, NH, NJ, NY, NC, OH, PA, RI, TN, VT, VA, WA, WV, and WI). Potato growers, crop consultants, and Extension personnel in states which grow Maine potatoes should remain vigilant by scouting their fields for Dickeya symptoms on a regular basis and by submitting any suspect samples for diagnostic testing. Dickeya dianthicola has been detected in the US in the past, and because of this, APHIS just recently announced that the pathogen has been designated as a non-reportable/non-actionable pathogen despite its potential to cause 100% crop loss. A link to the USDA/APHIS website for information on Dickeya dianthicola detection and control can be found here.

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

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 Potato Board

Dickeya discussion at National Plant Board meeting in Wilmington, DE

The National Plant Board will be holding their annual meeting in Wilmington, DE on July 31 to August 4th. The National Plant Board plays a significant leadership role in regulation and policy rules in agricultural production with each state having a representative member. One of the topics of discussion will be Dickeya dianthicola which has caused significant problems in potato production in NJ other states in the mid-Atlantic region. There will be presentations on Dickeya and seed potato production on the morning of Wednesday August 3rd starting at 8:15 AM.  More information on the meeting and the schedule can be found here.