Issue link: http://read.uberflip.com/i/957555
32 POTATO GROWER | APRIL 2018 Diggin' In Diggin' In Diggin' In Diggin' In Diggin' In Diggin' In EARLY BLIGHT | Industry Report Protecting against early blight and improving yield potential Earlier than Early There are many diseases that can threaten the survival of a potato crop. A prime example is early blight. Research completed in 2013 by University of Idaho Extension showed that crop losses due to early blight can exceed 20 percent if left uncontrolled. The same research showed that in potato-growing regions, the use of fungicides can help decrease these crop losses to less than 5 percent. When determining how to control diseases like early blight, growers should plan early and consider fungicides as a part of their disease management plan. "To best prepare for any diseases that may affect their crop, potato growers should develop a fungicide plan prior to the season, so that they are prepared to make timely applications," says Curtis Rainbolt, a BASF technical service representative based in Idaho. "Endura fungicide is a product we recommend growers use for control of early blight and ultimately to help prevent crop losses." When such a high risk is associated with uncontrolled early blight, growers should carefully monitor their crop for signs of this and other diseases. TIMING IT RIGHT Although its name would imply that early blight appears early on in the growing season, it rarely does and often appears on mature foliage. Growers should keep this in mind and try to time applications of fungicides to their crop carefully. During the vegetative stage, application of foliar fungicides for early blight control is typically not necessary, as plants are still relatively resistant. Fungicide application that occurs too early could have minimal to no effect on the spread of early blight. Instead, growers should wait for the optimal time to apply fungicides. While growers should continually monitor their fields for signs of disease, fungicides should be applied preventively to avoid disease development. Rainbolt recommends applying fungicides on a tight spray schedule of five to 14 days depending on the location and disease pressure, in accordance with the label. This is especially important in weather conditions that can be breeding grounds for disease-causing fungi. In the case of early blight, alternating wet and dry periods favor disease production.