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Corn Diseases

All Corn Diseases Content

a green melon hangs on a trellis

SDSU Extension to host Corn and Melon Disease Workshop at SDSU Southeast Research Farm

August 08, 2023

Field corn, sweet corn and specialty melon growers looking to learn more about identifying and managing common diseases in their crops are invited to attend the South Dakota State University Extension Corn and Melon Disease Workshop.

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.

aerial view of South Dakota farm and surrounding land

Crops

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

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.

Hail-damaged corn field.

Are Fungicides Needed on Crops Damaged by Wind, Sand Blasting or Hail?

When extreme weather brings hail and sand blasting to fields, many growers wonder if a fungicide application is needed afterwards to protect wounded plants from bacterial diseases.

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.

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.

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.

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

Goss’s Bacterial Wilt and Blight Developing

While out scouting corn fields (the week of August 11, 2020) Goss’s bacterial wilt and blight was found starting to develop in a number of fields.