- Basil downy mildew has been reported in New Jersey. With current weather conditions all basil growers should scout on a daily basis and taking appropriate preventative measures.
- Cucurbit downy mildew has been reported on cucumber as far north as central North Carolina as of 6/20. To track cucurbit downy mildew in the US please visit http://cdm.ipmpipe.org/
- No late blight has been reported in the region. Late blight has been found as far as North Carolina to-date. To track late blight in the US please visit http://usablight.org/.
Archives for June 2014
June 21, 2014 Andy Wyenandt
Vegetable Disease Briefs – 6/21/14
June 21, 2014 Andy Wyenandt
Vegetable Disease Update – 6/21/14
Cole Crops
Downy mildew and Alterneria were confirmed on collard greens this past week. Current weather conditions are ideal for the development of both diseases on all cole crops as well as other crops.
Symptoms of downy mildew on cole crops include the production of white spore masses only on the undersides of infected leaves. The tops of leaves will develop slightly chlorotic (i.e., yellow) spots on the upper leaf surface that become papery in texture.
Alternaria typically starts out as small pinpoint spots on infected leaves that enlarge up to 2 inches. Lesions will become tan, brown or black and may have concentric rings and leave ‘shot holes’ in leaves.
Control of both diseases begins with regular scouting and preventative fungicide programs. Control of downy mildew is best with downy mildew specific fungicide such as Presidio (fluopicolide, 43) at 3.0 to 4.0 fl. oz 4SC/A, or Revus (mandipropamid, 40) at 8.0 fl. oz 2.08SC/A, or Zampro (ametoctradin + dimethomorph, 45 +40) at 14.0 fl. oz 4.38SC/A included in tank-mix with chlorothalonil (M5) at 1.5 pt/A. A phosphite fungicide (FRAC group 33) such as Prophyt, Rampart, or K-Phite can be included to also help control downy mildew. For control of Alternaria, apply chlorothalonil (M5) at 1.5 pt/A alone, or tank-mixed with a FRAC code 11 fungicide such as Quadris (azoxystrobin, 11) at 6.0 to 15.5 fl. oz 2.08F/A or Cabrio (pyraclostrobin, 11) at 12.0 to 16.0 fl. oz 20EG/A, or Fontelis (penthiopyrad, 7) at 14.0 to 30.0 fl. oz 1.67SC/A.
June 19, 2014 A.Wyenandt, W.Kline, and J.Ingerson-Mahar
Potato Disease Forecasting Report 6-20-14
Potato Disease Forecasting Report 6-20-14 – Click To Download
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 New Jersey. 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.
June 19, 2014 A.Wyenandt, W.Kline, and J.Ingerson-Mahar
Tomato Disease Forecasting Report 6-20-14
6-20-14 Tomato Report – Click to Download
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.
June 19, 2014 Jim Murphy
Crabgrass Emerging
Crabgrass has been emerging for several weeks now, depending on the exposure. Warmer and more open turfs will likely have more advanced (larger) plants while cooler and denser turfs will have smaller plants.
Management options for this weed at this point in the season range from doing nothing to postemergence herbicide applications.
Relatively small crabgrass plants (most pre-tillering stage) emerging
from a footpath on June 11th.
June 18, 2014 Kris Holmstrom and Joe Ingerson-Mahar
Veg IPM Update: Week Ending 6/18/14
Vegetable IPM Report 6-18-14 – Click to View | Download | Print
Maps for the WeekClick Image to View
–European Corn Borer Population Map
–Corn Earworm Moth Blacklight Trap Map
–Corn Earworm Moth Pheromone Trap Map
–Pepper Weevil Trap Catch Map
Topics for the Week
- Sweet Corn
- Cole Crops
- Peppers
- Pepper Weevil Report
- Tomatoes
- BMSB
- Pumpkins and Winter Squash
- Snap Beans
