07/26/05 Late blight found in a pair of fields

You had to figure it was coming. All of the signs were there for late blight in southern Idaho potato fields following a cool, wet May and June. Sure enough, reports out of Canyon County indicate that the blight has been found in two fields. The blight appeared to have started in an area that looked like a drowned out spot but further investigation showed that lesions were scattered throughout the field. A second potato field nearby was found to have a very light infestation. HOTLINE "Growers in the Treasure Valley who do not have late blight should spray immediately if no applications have been made and continue on a weekly basis with a protectant fungicide." That's the advice that is giving out through the University of Idaho late blight hotline. As long as the weather remains hot, and it certainly was that last week and will be most of this week, the spread of the pathogen will be slow. The U of I experts are recommending that growers in other regions of the state stay on a ten to 14 day fungicide schedule but fields need to be scouted intensively. Wet areas should be scouted two to three times each week and the U of I believes the threat of blight is high for all areas of the state and most likely will appear outside Canyon County. Updates on blight and other problems are available through the Internet at www.pnwpestalert.net or the hotline at 1-800-791-7195. Today's Idaho Ag News Bill Scott