Friday, 23 August 2013 22:15

Fungicides for Managing Potato Late Blight

Late blight in fungicide test plots Late blight in fungicide test plots Jeff Miller

There are a lot of fungicides available for managing late blight. One of the attached articles discusses what to use and how to use it. The other lists steps growers can take approaching harvest and going into storage.

Late blight was identified in central Bingham County on July 10 and has since been found in many areas in eastern Idaho.  Thundershowers create the ideal conditions for the spread of the late blight pathogen and the development of disease.  It is important to protect potatoes (and tomatoes).  Cool, wet weather, the amount of life left in the vines, and the proximity of your crop to late blight are all important considerations for deciding on whether to spray with fungicides.  Fungicides are effective in protecting potatoes and tomatoes from infection by the late blight pathogen if used properly.  The first article linked here discusses many of the fungicides labeled for controlling late blight, along with a brief discussion on application methods and frequency of application.  The second provides a checklist growers can follow to manage late blight at the end of the growing season and into storage.  The third gives an update of the epidemic in southern Idaho as of August 7, 2015.