Kansas corn farmers have new tools to guard against corn leafhoppers and corn stunt disease. The Kansas Corn Commission is supporting the work of K-State Plant Pathologist Rodrigo Onofre, PhD to track leafhoppers and corn stunt disease in Kansas to help growers manage this risk. Corn leafhoppers and corn stunt were found in Kansas for the first time in 2024. Because early detection of corn leafhoppers is vital to avoiding corn stunt, a monitoring system and webpage have been created to help growers to track corn diseases.

Dr. Onofre is leading a collaborative effort between K-State Plant Pathology, the Kansas Corn Commission, Kansas Independent Crop Consultants, K-State Research & Extension Ag Agents, and Corteva to monitor at least three counties in each crop reporting district for corn leafhoppers. A webpage at kscorn.com/new-site/ has been created to track the corn leafhoppers, corn stunt and other diseases.

About 33 Kansas participants are receiving sticky traps and sending them back to Onofre’s lab weekly to track the number and location of corn leafhoppers. The monitoring system has started and will continue for 40 weeks. The leafhoppers that are trapped will be tested to see if they carry the corn stunt disease. Any detections will be added to a map that tracks corn leafhopper detections in Kansas and other states. Additionally, Dr. Onofre will be offering free corn stunt disease testing for Kansas corn growers during the 2025 season in both types of samples—corn tissues and corn leafhoppers.

Corn leafhoppers that carry the bacteria can transmit the pathogen to corn plants causing the corn stunt disease. The white-colored pest responsible for vectoring corn stunt can be identified by the dark spots between their eyes and a V-shaped marking on their thoracic segment.

The corn leafhopper map, along with a map that tracks the detection of corn stunt disease are featured on Kansas Corn’s corn disease webpage at http://kscorn.com/corndisease. The corn disease webpage also shows maps for tar spot and southern rust as well as video reports from Dr. Onofre and other corn disease news and information.

Mapping of the movement of the corn leafhopper is key. Dr. Onofre said controlling corn stunt starts with mitigating the number of corn leafhoppers in a field. Because the disease, carried by corn leafhoppers is a bacterial pathogen, fungicides are ineffective as a treatment.

Visit kscorn.com/new-site/corndisease for more information.

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