Goss's Wilt in Corn

Goss’s wilt occurs as either a vascular wilt (early-season) or leaf blight (mid-season). Leaf blight may result in large areas of necrotic leaf tissue, which interferes with photosynthesis. Corn should be scouted after severe weather because injury from hail or high winds usually plays a direct role in initial infection.

Plant Symptoms. Leaf blight appears as long, gray-green to black, water-soaked streaks extending along leaf veins. Small, dark, water-soaked flecks, referred to as freckles, often occur inside larger lesions and at the edges of lesions where symptoms are advancing. Leaf freckles are luminous when lighted from behind. Bacterial cells may ooze from infected leaves and dry on leaf surfaces forming a shellac-like sheen (Figure 1).

Management. There are no in-season management options. Disease symptoms should be confirmed through laboratory diagnosis. Selection of corn products with improved levels of tolerance to Goss’s wilt is the primary management option. Tillage and rotation to another crop besides corn for two or more years can help infected residue to degrade, reducing the levels of inoculum.


Goss's Wilt

Figure 1. Identifying characteristics for Goss’s wilt: water soaked streaks (left) with leaf freckles that appear luminous when held up to block the sun (middle) and bacterial ooze (right).

 

Sources: Jackson, T. 2007. Goss’s bacterial wilt and leaf blight. Plant Disease Central. University of Nebraska. http://pdc.unl.edu. Web sources verified 8/13/18. 150803120531