Severity index rises, but no late blight in spuds yet
Severity values for late blight in potatoes are rising in eastern North Dakota and western Minnesota, but no cases of the potentially devastating crop disease have been reported yet.
The updated North Dakota State University Potato Blightline for late June, sponsored by Syngenta Crop Protection, found that late blight severity values continue to rise because of wet, cool weather. Severity values are based on weather and accumulate when mild, wet conditions foster development of late blight, which can hammer both yields and quality.
The Northern Plains Potato Growers Association, based in East Grand Forks, Minn., says severity values are high enough in some locations to warrant applying a protective fungicide. The group notes that Chlorothalonil, one such fungicide, is in short supply this year and could be difficult to find.
Potato growers are urged to scout fields for late blight early and all season, paying particular attention to areas near shelterbelts and low-lying spots where moisture persists.
For more information on the NDSU Blightline, visit www.ndawn.ndsu.nodak.edu. Click on