Archives for July 2016

July 28, 2016 A.Wyenandt, W.Kline, and J.Ingerson-Mahar

Potato | Tomato Disease Forecast 7-29-16

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 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 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

Rutgers, The State University of New Jersey

Filed Under: Disease Forecasting

July 28, 2016 Dean Polk, Dave Schmitt, Atanas Atanassov, Carrie Mansue

Fruit IPM for 7/28/16

Peach:

Cat-facing Insects, Tarnished Plant Bug (TPB) and Brown Marmorated Stink Bug (BMSB): BMSB traps show only very low levels of bugs. Where ground cover consists of numerous flowering weeds, TPB population is very high. Up to 37 adults and nymphs per 50 sweeps were seen this past week in northern counties. [Read more…]

Filed Under: Blueberry, Fruit, Tree Fruit, Wine Grape

July 28, 2016 Cesar Rodriguez-Saona

The Cranberry Toad Bug – An Emerging Pest of Cranberries

We are seeing nymphs of toad bugs in cranberry beds. Growers need to be aware of this insect and treat if numbers reach high levels (there is no current threshold). We are currently conducting studies to estimate the density of toad bugs that can cause economic injury to cranberries.

Life cycle. Toad bugs, Phylloscelis atra, feed only on cranberries. This insect has a single generation per year. It overwinters as eggs. The nymphs appear by the end of June through August, and the adults from August through October. Eggs are laid from September through October. [Read more…]

Filed Under: Cranberry, Fruit

July 28, 2016 Andy Wyenandt

Reminder: Dickeya discussion at National Plant Board meeting in Wilmington, DE on Weds. 8/3

The National Plant Board will be holding their annual meeting in Wilmington, DE on July 31 to August 4th. The National Plant Board plays a significant leadership role in regulation and policy rules in agricultural production with each state having a representative member. One of the topics of discussion will be Dickeya dianthicola which has caused significant problems in potato production in NJ other states in the mid-Atlantic region. There will be presentations on Dickeya and seed potato production on the morning of Wednesday August 3rd starting at 8:15 AM. More information on the meeting and the schedule can be found here.

Filed Under: Vegetable Crops Tagged With: Dickeya, National Plant Board

July 27, 2016 Andy Wyenandt

Cucurbit downy mildew confirmed on cucumber in North Jersey 7-27-16

Cucurbit downy mildew has been confirmed on cucumber in Hunterdon County in Northern New Jersey. Downy mildew was found in cucumber in the southern part of the state a few weeks ago. To date, cucurbit downy mildew has only been reported in cucumber in the mid-Atlantic region. All cucumber growers who have not included a downy mildew-specific fungicide in their weekly spray program should do so. For more in formation on controlling cucurbit downy mildew please see the 2016 Mid-Atlantic Commercial Vegetable Production Recommendations Guide.

Filed Under: Vegetable Crops

July 27, 2016 Kris Holmstrom and Joe Ingerson-Mahar

Veg IPM Update: Week Ending 7/27/16

Sweet Corn

European corn borer (ECB) moth activity is slowly increasing and spreading northward (see ECB map) . This is the early part of the second flight. Very few larval infestations have been detected. 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…]