This article summarizes key points about this disease, including where it has been confirmed in Minnesota, factors that favor its development, and how to recognize it.

Goss's wilt was first confirmed in Minnesota in 2009.

By the end of 2011, it was found in many fields in over 30 counties across southern Minnesota and into the lower Red River Valley. This disease caused only minor damage and minimal yield loss in most fields. However, yield loss was significant in some fields.

There appears to be a risk for this disease across much of the Minnesota corn production area. Risk for individual fields, however, will likely vary from very low to higher based on environmental conditions and field history.

There is no complete understanding of all the factors that lead to development of Goss's wilt in a field. The pathogen survives between crops in infected corn residue near the soil surface.

Goss's wilt may be more likely to develop under certain conditions:

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  • where fields are planted with hybrids susceptible to Goss's wilt
  • in fields or areas where this disease has occurred in the past two years, where much infected corn crop residue remains near the surface
  • in fields that have been in continuous corn and have not been rotated
  • perhaps where corn plant populations are high
  • where leaves are injured by hail or strong winds accompanied by blowing rain and sand/soil

Goss's wilt can appear throughout the season. It was seen primarily in August in the past two years in Minnesota. 

It kills leaf tissue and also can infect stalks and kill entire plants.

The leaf symptoms begin first as dark green water soaked areas with dark spots often called "freckles." These areas usually develop into large elongated tan lesions with irregular margins. Dark green spots and shiny patches of dried bacterial ooze that looks like dry egg-white develop in the lesions.

Samples can be sent for diagnosis to the University of Minnesota Plant Disease Clinic. They can be reached at (612) 625-1275.

Some things to consider doing this season related to Goss's wilt are to learn how to recognize this disease, scout fields and have appropriate diagnosis done to document which fields have Goss's wilt, and check hybrids to determine how well they are resisting development of Goss's wilt.  

At this point, there is minimal information available to suggest how effective any foliar product is for managing Goss's wilt. But if tempted to try a product, please leave untreated check strips in fields so you can compare disease and yield levels to assess product efficacy.  FG

—From Minnesota Crop News

PHOTO
Photo courtesy of Dean Malvick.