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

Archives for July 2016

July 20, 2016

Veg IPM Update: Week Ending 7/20/16

Sweet Corn 

16ecb0720a European corn borer (ECB) moth activity is now increasing in a few areas of the state (see ECB map) .  Larval infestations have yet to appear.  Be sure to begin monitoring plantings for ECB feeding while they are still in the whorl stage.  Consider treating when the number of infested plants in a 50 plant sample exceeds 12%.  Feeding in the whorl stage will appear as numerous small holes (called “shot-hole”) on leaves, with damage present on consecutively younger leaves. As plants progress to pre-tassel and beyond, droppings and  larvae may be found in or on the emerging tassels.  Any planting remaining at or above threshold as it proceeds to full tassel should be treated, as this is the last stage at which ECB larvae will be exposed and vulnerable to insecticidal sprays.    [Read more…]

Filed Under: Vegetable Crops
July 20, 2016

Fruit IPM for 7/19/16

 

Peach:

Oriental Fruit Moth (OFM): The third flight is underway in southern counties, and about to start in northern counties. Populations are low in peaches, but higher in apples. [Read more…]

Filed Under: Blueberry, Fruit, Tree Fruit, Wine Grape
July 19, 2016

Cucurbit powdery mildew control in 2016

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.

Filed Under: Vegetable Crops
July 19, 2016

Vegetable Disease Briefs – 7/19/16

  • 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.
  • Basil downy mildew has been confirmed in southern and central New Jersey. All conventional basil growers should be on a preventative spray program prior to the arrival of the disease.
  • Reports of Dickeya dianthicola in potato continue across the east coast. Dickeya dianthicola has been confirmed in 10 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.
Filed Under: Vegetable Crops
July 18, 2016

Potato | Tomato Disease Forecast 7-19-16

Click to View | Download Report 7-19-16

Potato Disease Forecasting Report

We will be tracking DSVs for Late blight development and calculating P-days for initiating the first early blight fungicide application.

The first late blight fungicide application is recommended once 18 DSVs accumulate from green row. Green row typically occurs around the first week in May in southern NJ. An early season application of a protectant fungicide such as mancozeb (Dithane, Manzate, Penncozeb) or Bravo (chlorothalonil) as soon the field is accessible is suggested. Please be vigilant and keep a look out for suspect late blight infections on young plants. No late blight has been reported in our region to date.

Remember the threshold for P-days is 300!  Once 300 P-days is reached for your location early blight fungicide applications should be initiated. Growers who are interested in using this model should chose the location above that is closest in proximity to their farming operation and should regularly check the Cornell NEWA website (http://newa.cornell.edu/) where this information is compiled from. Click on Pests Forecasts from the menu, select your weather station, and click on tomato diseases, set accumulation start date and a table of daily and total DSVs will be generated.

Tomato Disease Forecasting Report

Disease severity values (DSVs) for early blight, septoria leaf spot, and tomato anthracnose development are determined daily based on leaf wetness (due to rainfall, dew) and air temperature.

On a daily basis DSV values can range from 0 to 4 where 0 = no chance for disease development to 4 = high chance for disease development.
DSVs are accumulated during the production season.

Fungicide applications are based on an individually determined DSV threshold. The first fungicide application for the control of these three diseases is not warranted until 35 DSVs have accumulated from your transplanting date. After that, growers can base fungicide applications on different DSV thresholds.

Reports generated by Ryan Tirrell

Filed Under: Disease Forecasting
July 15, 2016

Dickeya dianthicola: Looking for feedback from potato growers

An article by Rosemary Gordon in Growing Produce, the online version of American Vegetable Grower, outlines the problems caused by Dickeya dianthicola that some potato growers in the Eastern U.S. are facing this summer. The article is looking for feedback from those potato growers affected by Dickeya either this summer or last as University researchers from across the country look to improve methods to detect, monitor, and develop management strategies for the pathogen. Dickeya, which is seed borne, has been shipped on seed of some potato varieties originating from Maine and Canada to 10 states along the East coast thus far this growing season. Feedback provided by growers go a long way in helping researchers develop and validate detection, monitoring, and management strategies. To read the article and help please see link below.

Dickeya: A new potato disease

For more information on Dickeya please click here.

 

Filed Under: Vegetable Crops Tagged With: