June 1, 2018

Welcome to the first NDSU Potato Blightline for 2018 sponsored by Syngenta Crop Protection. We are up and running for the 24th consecutive year of operation. The Blightline includes disease forecasting and control recommendations for late blight and early blight, and other potato disease and insect information on a local and national basis. The Blightline is updated weekly, or more often if late blight is present, through mid-September. Information and recommendations are available anytime through the toll free number 1.888.482.7286 and the NDSU Potato Late Blightline at www.ndawn.ndsu.nodak.edu. On the website, click on applications, select potato, and choose late blight. There is also a link there to the NDSU Plant Pathology Late Blight website at this site.

The NDAWN website for potato disease forecasting uses both tabular data and colored maps of ND and western MN to illustrate quickly the late blight severity values (both two day and seasonal) and favorable day values, and P-day values for early blight throughout ND.

Current recommendations:

Potato season is off to a good start and it is not too early to remind the potato community to prepare for late blight. Late blight was found in several areas of our region last year in early August, including southern Manitoba, northeastern North Dakota, and central and western Minnesota. Infected seed and volunteers are sources of inoculum for late blight and could be sources of late blight for our area in 2018. The risk of late blight now is low due to our warm May, but wet weather during the season will provide conditions favorable for late blight if inoculum is present.

Preventing first sources of late blight is a critical part of late blight management. These sources of initial inoculum are culls, volunteers and seed. Infected seed can be an early source of late blight inoculum, and we recommend scouting fields for late blight early, often and all season.

Thank you for using the NDSU Blightline.