- 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.
Archives for August 2017
August 22, 2017 Andy Wyenandt
Vegetable Disease Update – 8/22/17
August 21, 2017 A.Wyenandt, W.Kline, and J.Ingerson-Mahar
Potato | Tomato Disease Forecast 8-22-17
Click to View | Download Report 8-22-17
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 as the field is accessible is suggested. Please be vigilant and keep a lookout 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 choose 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
Rutgers, The State University of New Jersey
August 17, 2017 A.Wyenandt, W.Kline, and J.Ingerson-Mahar
Potato | Tomato Disease Forecast 8-18-17
Click to View | Download Report 8-18-17
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 as the field is accessible is suggested. Please be vigilant and keep a lookout 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 choose 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
Rutgers, The State University of New Jersey
August 16, 2017 Kris Holmstrom and Joe Ingerson-Mahar
Veg IPM Update: Week Ending 8/16/17
Sweet Corn
European corn borer (ECB) catches have been largely contained to Hunterdon and Somerset counties this past week (see ECB map at left). This flight has been very sporadic. ECB feeding in NJ sweet corn plantings is very low, and has been largely obscured by fall armyworm (FAW) feeding. Check 5 plants each in 10 random locations for a 50 plant sample. Look for “shot-hole” injury, and consider treating when the number of infested (from ECB or FAW) plants in a 50 plant sample exceeds 12%. As infested plants proceed to the pre-tassel stage, live larvae and damage may be found in the emerging tassels. Once plants hit full tassel, ECB larvae will move downward on the stalk and re-enter the plant near the area where ears are forming. This can result in direct injury to the ear. Growers should consider an insecticide application at the full tassel stage to target ECB larvae as they migrate downward. This application can eliminate larvae that have escaped any earlier insecticide applications. [Read more…]
August 16, 2017 Dean Polk, Dave Schmitt, Atanas Atanassov, Carrie Denson
Fruit IPM for August 16, 2017
Peach:
Spotted Wing Drosophila (SWD), Crop Diversity, Alternate Hosts, Wild Grape, Tall Trees and ‘Ready to Eat Fruit, Table-Ripe’ Fruit: Some farms, particularly in northern counties have diverse crops where stone fruit, raspberries, blackberries, blueberries, strawberries, and cherries (all SWD hosts) are grown on the same farm and often next to or close to each other. These same farms may be surrounded by woodlands that include wild chokecherry, wild grape, maturing pokeweed and other alternate hosts for SWD. As the season progresses, be aware that SWD populations go in only one direction – UP! The later the season, then the higher the population, and the greater the pest pressure. This means that the likelihood of infestation is increased, while control is made more difficult if sprays are skipped.
August 14, 2017 A.Wyenandt, W.Kline, and J.Ingerson-Mahar
Potato | Tomato Disease Forecast 8-15-17
Click to View | Download Report 8-15-17
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 as the field is accessible is suggested. Please be vigilant and keep a lookout 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 choose 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
Rutgers, The State University of New Jersey
