Potato and Tomato Disease Forecasting
Growers who are interested in using disease forecasting models should chose the location from the report that is closest in proximity to their farming operation.
In addition, regularly check the Cornell NEWA website @http://newa.cornell.edu/ where this information is compiled from. From the NEWA site menu click on Pests Forecasts, select your weather station, and click on the specific disease, set accumulation start date, and a table of daily and total DSVs will be generated.
Related Websites
Late Blight Reported in Erie County, NY and Cambria Couny, PA
Late blight was reported on potato in Erie County, New York and Cambria County, PA (west central) late last week. This is the first report of late blight in PA this season. There are also suspected cases of late blight are being reported on potato and tomato in Lancaster County, PA.
All tomato and potato growers in New Jersey should begin to scout their fields on a regular, if not daily basis. There have been no reported cases of late blight in New Jersey to date! However, all growers (conventional and organic) who have not initiated protectant fungicide maintenance programs should consider doing so. For organic growers, preventative copper applications should be considered. For more information on controlling late blight please see the 2014 Commercial Vegetable Fungicide Recommendations Guide.
Potato Disease Forecasting Report 6-24-14
Potato Disease Forecasting Report 6-24-14 – 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.
Tomato Disease Forecasting Report 6-24-14
6-24-14 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.
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.
