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Corn Diseases

All Corn Diseases Content

aerial view of South Dakota farm and surrounding land

Crops

During the growing season, SDSU Extension provides weekly production recommendations.

Three corn cobs with common ear rots. From left: Fusarium ear rot, Gibberella ear and Diplodia ear rot.

Scout for Corn Ear Rots

Several corn fields scouted in northeastern South Dakota counties were found with ear rots. Ear rots were mostly prevalent in areas that experienced hailstorms in the recent past. Ear rots in corn are caused by a few fungal pathogens, and which ear rot develops depends on the weather conditions.

corn field with sunrise in the background

Corn

Nearly one out of every three dollars generated by South Dakota agriculture starts in a corn field. Two of every three rows of corn become ethanol.

Tan-gray Goss’s bacterial blight lesions were observed in scouted corn fields.

Goss's Bacterial Wilt and Leaf Blight of Corn

Fact sheet for identifying Goss’s bacterial wilt and leaf blight of corn, also known
as bacterial leaf freckles and wilt.

Young farmer examining soybean plants n a field at sunset.

Be Aware of Fungicide Resistance in Field Crops

A few soybean and corn fields have received or will be receiving a fungicide application this season. We recommend scouting fields treated with fungicides to determine if diseases are controlled as expected or if there are signs of reduced sensitivity.

filed of sunflowers in bloom

2021 South Dakota Pest Management Guides Now Available

February 04, 2021

SDSU Extension has released the 2021 South Dakota Pest Management Guides.

A map of South Dakota with yellow and green circles indicating iverson risks at various locations throughout the state.

Use the SD Spray Tool for Inversion Detection and Weather for Pesticide Application

The SD Mesonet Spray Tool provides real-time weather data for pesticide applicators. This dedicated website for pesticide applicators uses the SD Mesonet weather data, which is updated every five minutes.

Left: A corn ear showing Gibberella ear rot symptoms. Right: A prematurely dried corn stalk split to reveal pith disintegration due to stalk rot.

Corn Ear Rots and Stalk Rots: The Last Issues To Check for in Corn Before Combining

Before combining corn, it is recommended to scout your field for corn ear rots and stalk rots. It is important to scout corn fields for these two issues in order to make timely decisions on corn combining.

A middle portion of a corn leaf enlarged to show tan-brownish lesions with dark brown wavy margins.

Bacterial Leaf Streak of Corn: A New Corn Disease in South Dakota

Bacterial leaf streak, caused by Xanthomonas vasicola pv. vasculorum (Xvv), is a recently discovered disease of corn in South Dakota. The disease was first identified in Nebraska in 2016 but now has been found in the majority of the Corn Belt states. Under favorable weather conditions bacterial leaf streak can develop to reach yield reducing levels. Like any other bacterial disease, once symptoms develop there is little that can be done to control it in the field. However, it is important to correctly diagnose this as a bacterial disease because it can be confused with gray leaf spot which is a fungal disease.

corn field with sunrise in the background

Best Management Practices for Corn Production

iGrow Corn is your unbiased, research-based guide to corn production, providing the latest recommendations to help increase yield, reduce input costs and protect your investment.