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.

May 21, 2019

Damping-off: Identifying and Controlling Early-Season Damping-off Pathogens

It is extremely important to know which pathogen is causing damping-off problems and which fungicide to properly apply. The key to controlling damping-off is being proactive instead of reactive. Always refer to the fungicide label for crop use, pathogens controlled, and application rates.

Damping-off is caused by a number of important vegetable pathogens and is very common during the spring. 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). Common pathogens that cause damping-off include Pythium, Phytophthora, Rhizoctonia and Fusarium spp.

Control of damping-off depends on a number of factors. First, is recognizing the conditions which may be leading to the problem (i.e., weather/greenhouse growing conditions) and second, identifying the pathogen causing the problem.

Conditions Favoring Damping-off

Although all four pathogens are associated with damping-off, the conditions which favor their development are very different. In general, Phytophthora and Pythium are more likely to cause damping-off in cool, wet or overwatered soils that aren’t allowed to dry out due to cloudy weather or cooler temperatures. Conversely, Rhizoctonia and Fusarium are more likely to cause damping-off under warmer, drier conditions especially if plug trays are kept on the dry side to help reduce transplant growth. [Read more…]

Filed Under: Organic Production, Vegetable Crops
May 21, 2019

Understanding Damping-off Pathogens During Seeding and Transplanting

Damping-off is caused by a number of important vegetable pathogens and is very common during transplant production and early-spring. 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). 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: ,
May 21, 2019

Vegetable Disease Update – 5/21/19

  • The cool, damp weather the past week has been ideal for downy mildew development on spring crops. Growers are advised to scout fields on a regular basis
  • The heavy rains and damp, cool weather have been ideal conditions for early-season damping off caused by Pythium. Growers should continue to scout on a regular basis and remain proactive in their fungicide programs as long as current weather patterns continue.
  • Cercospora leaf spot on swiss chard has been reported.
  • Bacterial leaf spot of parsley has been reported.
  • Basil downy mildew has been reported in greenhouses in North Carolina.
  • Cucurbit downy mildew has been reported as far north as St. Lucie County, Florida.
  • For more information on controlling these and other important diseases please see the 2019 Mid-Atlantic Commercial Vegetable Production Guide. The guide is available for FREE online by following the links on the Plant and Pest Advisory website. Hardcopies of the 2019 guide can be purchased through your local county Extension office.
Filed Under: Vegetable Crops
May 14, 2019

Vegetable Disease Update – 5/14/19

  • The cool, damp weather the past week has been ideal for downy mildew development on spring crops. Growers are advised to scout fields on a regular basis
  • The heavy rains and damp, cool weather have been ideal conditions for early-season damping off caused by Pythium. Growers should continue to scout on a regular basis and remain proactive in their fungicide programs as long as current weather patterns continue.
  • Sunburn on stems of newly transplanted peppers on black plastic mulch has been reported.
  • Cercospora leaf spot on swiss chard has been reported this past week.
  • Cucurbit downy mildew has been reported as far north as St. Lucie County, Florida.
Filed Under: Vegetable Crops
October 2, 2018

An Introduction To Rutgers Downy Mildew Resistant Sweet Basils

After nearly a decade’s worth of research and breeding efforts Rutgers Downy Mildew Resistant (DMR) sweet basils are now available to commercial growers with seed for homeowners and gardeners becoming available in 2019. Since 2007, when basil downy mildew (BDM) was first identified in FL, the disease has caused significant economic losses to commercial basil growers throughout the United States, and has made growing sweet basil in the backyard garden nearly impossible. Since 2009, Rutgers has been working diligently to identify and breed downy mildew resistance into commercially-acceptable sweet basils that have the correct aromas, essential oils, and flavors. The first of these three new DMR sweet basils are now available through VanDrunen Farm Specialty Seed (VDFSS) located in Thermal, CA and Momence, IL. Each of the new Rutgers DMR sweet basils have their own unique characteristics which can be matched to meet grower needs.

Rutgers Obsession DMR: An excellent sweet basil for field or potted plant production; will also make an excellent edible landscape plant; more compact, slower growth than Devotion DMR and Thunderstruck DMR, high leaf-to-stem ratio – good for small bunches or small size clam shells, dark green, thick, glossy leaves, flowers form late; and highly resistant to Fusarium wilt.

Rutgers Devotion DMR: An excellent Genovese-type sweet basil for field production for fresh markets; establishes quicker than Obsession DMR with uniform, upright growth, dark, green color with flat to cup-shaped leaves.

Rutgers Thunderstruck DMR: An excellent sweet basil with high yields needed for processing- and fresh-market production; quick establishment and fast, upright growth with medium-sized, ruffled leaves with a bright green color.

Rutgers Obsession DMRRutgers Devotion DMRRutgers Thunderstruck DMR

 

 

 

 

 

 

 

 

 

For more information on Rutgers DMR sweet basils please contact VanDrunen Specialty Seeds in the link above. For more information on basil downy mildew, our research, and our new DMR sweet basils follow us on Instagram at #RutgersBasil.

 

Filed Under: Vegetable Crops Tagged With: ,
October 1, 2018

Vegetable Disease Update – 10/01/18

  • Anthracnose fruit rot has been found on pumpkin.
  • Bacterial stalk rot in sweet corn has been reported.
  • Downy mildew has been reported in bok choy. Cole crops, as well as leafy greens, need to be scouted on a regular basis and preventative sprays applied as long as wet weather continues.
  • Pepper anthracnose has been reported. If found in field, weekly fungicide maintenance sprays are needed. Abandoned fields should be mowed down immediately.
  • Bacterial leaf spot and Phytophthora blight and fruit rot remain active in pepper and cucurbit crops.
  • Alternaria leaf spot has been reported on broccoli.
  • Anthracnose has been reported in turnip.
  • Cercospora leaf spot has been reported on swiss chard and beets.
  • Basil downy mildew is being reported. Recent weather has been ideal for its development. For more information on Rutgers newly-released DMR sweet basils Obsession, Devotion, and Thunderstruck please click here. Follow the Rutgers Basil Downy Mildew Breeding Program on Instagram at #RutgersBasil
Filed Under: Vegetable Crops