Sweet Corn
European corn borer (ECB) catches remain low generally, with a few remaining hot spots in southern Hunterdon County and on the Cumberland-Salem border (see ECB map). Feeding in NJ sweet corn plantings has risen, with some plantings exceeding 40%. 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 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 (see bottom photo at right). 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…]
Archives for June 2017
Veg IPM Update: Week Ending 6/21/17
Potato | Tomato Disease Forecast 6-20-17
Click to View | Download Report 6-20-17
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.
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
Potato | Tomato Disease Forecast 6-16-17
Click to View | Download Report 6-16-17
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.
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
Fruit IPM Update for 6/14/17
Blueberry:
General Insect Control and New and Renewed Labels: Late last week we obtained the Section 24C renewal for the high rate of Gowan Malathion 8F. The specifics of the label renewal are as follows: [Read more…]
Veg IPM Update: Week Ending 6/14/17
Sweet Corn
European corn borer (ECB) catches have stabilized, with significant catches remaining in central Morris County and in southern Hunterdon County (see ECB map). Feeding in NJ sweet corn plantings is increasing in occurrence, although severity of individual infestations has not risen dramatically. Overall, activity is lower than expected this year, likely due to adverse weather conditions. Feeding rates in the 20% range are common. 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 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 (see bottom photo at right). 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…]
Vegetable Disease Update – 6/14/17
- The extremely hot weather we are currently experiencing is likely to spur on Phytophthora blight development in pepper, tomato, cucurbit, and eggplant crops. For more on controlling Phytophthora blight click here.
- Suncald has been reported in newly transplanted peppers in south Jersey. Transplants laying against or on black plastic mulch; or in even some cases where the sun reflects off the mulch or soil, can cause sunburn on stems of plants that haven’t fully hardened off. Avoid transplanting on extremely hot and sunny days.
- Bacterial leaf spot was reported in tomato this past week.
- Downy mildew has been reported as far north as Northern Florida on multiple cucurbit crops and on cucumber in South Carolina and North Carolina to date.
- There have been no new reports of Late blight in the past week.