Rutgers University | New Jersey Agricultural Experiment Station | Pesticide User Responsibility

Andy Wyenandt

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

January 12, 2018

Best management practices for managing Dickeya dianthicola in potato.

Its the time of year when many potato growers (organic and conventional) are preparing to purchase seed potatoes for the upcoming season. Dickeya dianthicola was detected in ‘Dark Red Norland’ and ‘Kennebec’ seed being sold in retail establishments and in ‘Silverton’ in a commercial seed lot in NJ in 2017. Importantly, all growers are encouraged to follow best management practices for buying seed and best management practices for Dickeya in field production. North American Seed Health Certification records and Dickeya test results should be requested prior to purchasing any seed.  If you suspect Dickeya dianthicola in potato seed during purchasing, cutting, or planting please contact your county Extension agent or Extension Specialist. All suspect potato samples should be PCR tested to confirm the presence of Dickeya or Pectobacterium.

This past fall The University of Maine held a Dickeya and Pectobacterium Summit which was attended by over 150 people from all over the world. A nice summary of the meeting by Dr. Angela Madeiras can be found in the January 11, 2018 UMASS Vegetable Notes Newsletter here.

 The best method for keeping your potato operation Dickeya-free is to adopt your own 0% Dickeya-tolerance policy.

Filed Under: Vegetable Crops Tagged With:
September 24, 2017

Vegetable Disease Update – 9/24/17

  • Late blight has been reported in western NY and Long Island this past week. Late blight has not been reported on tomato or potato in NJ to date. If you suspect Late blight on your farm please contact your county Extension agent. To track the progress of Late blight in the US please visit USAblight.
  • Cucurbit downy mildew (CDM) continues to be reported throughout the region. All cucurbit growers are encouraged to continue to include downy mildew specific fungicides in their regular weekly maintenance programs. To track CDM movement in the US please visit the North Carolina State University’s CDM Forecasting Website.
  • Fusarium and Rhizoctonia root rot has been reported in Cilantro and parsley this past week.
Filed Under: Vegetable Crops
September 24, 2017

Understanding root rots in fall-seeded and transplanted crops

Damping-off is caused by a number of important vegetable pathogens and is very common at seeding and transplanting in spring and fall. Damping-off can kill seedlings before they break the soil line (pre-emergent damping-off) or kill seedlings soon after they emerge (post-emergent damping-off) or soon after transplanting. Common pathogens that cause damping-off include Pythium, Phytophthora, Rhizoctonia, and Fusarium spp.

It is extremely important to know which pathogen is causing the damping-off problem and which fungicide to properly apply.

[Read more…]

Filed Under: Vegetable Crops Tagged With:
August 30, 2017

Vegetable Disease Update – 8/30/17

  • Late blight has not been reported on tomato or potato in NJ to date. If you suspect Late blight on your farm please contact your county Extension agent. To track the progress of Late blight in the US please visit USAblight.
  • Cucurbit downy mildew (CDM) on cucumber continues to be reported throughout the region. All cucumber growers should add downy mildew specific products to their regular maintenance programs. CDM has also been reported on giant pumpkin, cantaloupe, and butternut squash in PA and on pumpkin and watermelon in DE, VA, and MD to date. All pumpkin and watermelon growers are encouraged to include downy mildew specific fungicides in their regular weekly maintenance programs. To track CDM movement in the US please visit the North Carolina State University’s CDM Forecasting Website.
Filed Under: Vegetable Crops
August 22, 2017

Vegetable Disease Update – 8/22/17

  • There have been a few reports of late blight in PA this past week. Late blight has not been reported in NJ to date. If you suspect Late blight on your farm please contact your county Extension agent. To track the progress of Late blight in the US please visit USAblight.
  • Cucurbit downy mildew (CDM) on cucumber continues to be reported throughout the region. All cucumber growers should add downy mildew specific products to their regular maintenance programs. CDM has also been reported on giant pumpkin, cantaloupe, and butternut squash in PA and on watermelon in VA and MD to date. To track CDM movement in the US please visit the North Carolina State University’s CDM Forecasting Website.
  • Bacterial canker and bacterial leaf spot in tomato are being reported.
  • Bacterial leaf spot is also being reported in pepper.
  • Pepper anthracnose has been reported in the past week.
  • Cucurbit powdery mildew and anthracnose in cucurbit crops have been reported.
Filed Under: Uncategorized, Vegetable Crops
August 10, 2017

Vegetable Disease Update – 8/10/17

  • Late blight (US-23) was reported on tomato in Chester County in Southeastern PA this week. US-23 is active on both tomato and potato. All NJ tomato and potato growers are encouraged to scout their fields on a daily basis. Late blight has not been reported in NJ to date. If you suspect Late blight on your farm please contact your county Extension agent. To track the progress of Late blight in the US please visit USAblight.
  • Cucurbit downy mildew (CDM) on cucumber continues to be reported throughout the region. All cucumber growers should add downy mildew specific products to their regular maintenance programs. CDM has also been reported cantaloupe and Butternut squash in PA. CDM has also been reported in pumpkin as far north as North Carolina. To track CDM movement in the US please visit the North Carolina State University’s CDM Forecasting Website.
  • Bacterial canker and bacterial leaf spot in tomato are being reported. Bacterial leaf spot is also being reported in pepper.
  • Pepper anthracnose has been reported in the past week.
  • Dickeya dianthicola has been reported in 6 states and in 9 potato varieties to date including Dark Red Norland, Red Pontiac, Silverton, Yukon Gold, Kennebec, Norwis, Superior, Marcy, and Vivaldi.
  • Surveying for Dickeya dianthicola in potato fields and irrigation sources in NJ is currently on-going. If you suspect Dickeya, please contact your county agent. The best method for controlling Dickeya dianthicola in your operation is to adopt a zero-tolerance policy.
  • Want more information of what is going on around the mid-Atlantic region? Just click on the links to articles written by Extension personnel from PA, DE, VA, and WV on the right side of the page! You can also sign-up with and have information sent directly to you just like the NJ – Plant and Pest Advisory.
Filed Under: Commercial Ag Updates, Vegetable Crops