"The Plant Pathology Department at North Dakota State University will again be providing the potato blightline service at no charge to the potato industry of North Dakota and western Minnesota. This will be the thirteenth year that this service has been provided and sponsored by Syngenta Crop Protection and Amistar fungicide. The hotline uses local weather data collected from weather stations throughout our area to forecast the occurrence and spread of late blight in fourteen non-irrigated and nine irrigated production areas in ND and western MN. The data is processed by the North Dakota Agricultural Weather Network (NDAWN) and analyzed by a computer program (WISDOM) to forecast when conditions are favorable for late blight to occur.

The forecast information is used by plant pathologists Gary Secor and Neil Gudmestad to make late blight management and fungicide recommendations. The recommendations are made Monday, Wednesday and Friday of each week during the growing season. The first late blight hotline will be Wednesday June 1st, and the hotline will continue through mid September depending on disease pressure. The hotline will also be used to confirm late blight infection and serve as clearing house for national late blight information. In addition to late blight forecasting, the hotline also provides cumulative P-values for early blight disease forecasting and management recommendations. Finally, it serves to alert growers of other disease and insect news, as well as posting messages of general interest such as potato field day dates.

The hotline recommendations can be accessed by phone or website. The toll free phone number is 888.482.7286. The NDAWN website for potato disease forecasting, produced by Dr. John Enz of the Soil Science Department at NDSU, uses colored maps of ND to pictorially illustrate the late blight severity values (both two day and seasonal), favorable day values and P-day values for early blight throughout ND.

Growers and scouts are encouraged to send suspect late blight samples to us for positive identification. It is important to receive samples as quickly as possible after collection. Leaf samples should be placed in a slightly inflated zip-lock plastic bag without a wet towel and sent to:

Gary Secor, Plant Pathology, Walster Hall 306, North Dakota State University, Fargo, ND 58105 . Our phone number is 701.231.8362 and email address is gary.secor@ndsu.edu. We look forward to a successful potato year.