A P R I L 2 0 1 8 18 POTATO GROWER We are excited to announce that we will posting the potato Blightline on a new app, called NDAWN Potato Blight. The NDAWN Potato Blight app is available on Apple and Android phones and tablets (z.umn.edu/potatoapp). The app is designed to provide field-specific information of when environmental conditions are favorable for early blight and late blight by entering in key field information. All Blightline messages and alerts will be sent through this app to potato growers in North Dakota and Minnesota (we will no longer be email- ing the Blightline). In previous years, the late blight and early blight models that were used for all potato acres in North Dakota were based on one average emergence and row clo- sure date for the state of North Dakota and therefore not accounting for indi- vidual field information. Potatoes can be planted during a two-month period from late April to late June in North Dakota and Minnesota; therefore, mak- ing this model inaccurate for some pota- to acres. The field-specific model now available on the NDAWN Potato Blight app will more accurately predict the best time to apply protectant fungicides to each potato field. After downloading the new app to your phone/tablet, log in using your phone number and verification code that you will receive via text message. The verifi- cation code is only valid for five min- utes. You can share access to your fields with others by having them log in with your phone number using the code that you receive. Once you are logged in, click on the “Fields” section, then go to “Add New Field” (Figure 1). You will need to fill in each required section for the model to work properly (Figure 2). Give the field a name, provide a plant- ing date, select a weather station, emer- gence date and row closure date (esti- mate if unknown) and enter any other information you would like to have on the field. If using estimated dates, the model will not accumulate any values for late blight or early blight models until these dates have weather data. Once the actual dates are known, you will want to update the dates to improve the accuracy of the model. Touch save and your newly created field will be saved in your field section. Repeat for other fields you would like to add. Once all the required information in enter into each field, the model will start accumulating favorable days. The threshold for early blight is 200 P-Days and for late blight it is a severity value of 15. When a field reaches the threshold for early blight or late blight, a notifica- tion will be sent to your phone or tablet that the particular field has reached a threshold value. There are some other neat features of the app. These include a data page that expresses the accumulated severity val- ues for the past 10 days in graph format (Figure 3) and weather data from any NDAWN station (Figure 4). The setting tab will allow you to adjust your notifi- cations. The push notifications that can be changed are Blightline updates, early blight alerts, late blight alerts and inver- sion alerts (Figure 5). If you have a ques- tion and would like to contact us, click on the “Contact Us” link. A video tuto- rial on how to use the app can be found at z.umn.edu/appvideo. It is intended that this potato blight application will be a convenient resource and assist in decision making. It allows each field to have alerts when severity values are at threshold and pro- vides messages with custom informa- tion, including local late blight out- breaks to each user. We hope to increase the accuracy of predicting late blight and early blight in order to decrease pes- ticide use and to improve prevention and control of these diseases. Andy’s Advice: NDAWN Potato Blight App By Andy Robinson, Extension Potato Agronomist, NDSU/UMN and Daryl Ritchison, Interim Director of the North Dakota Weather Network