The corn leafhopper (Dalbulus maidis) is a pest of corn that typically lives in warm places, such as areas near the coast in the southern United States. However, in 2024, it moved as far north as Minnesota in the Midwest and Georgia in the East. North Carolina corn growers can keep an eye out for this insect, but should not worry.
Adult corn leafhoppers are small, light tan insects with two dark spots between their eyes (Figure 1). They feed directly on corn leaves. More concerning than this feeding are the three pathogens they transmit that are associated with corn stunt disease: corn stunt spiroplasma, maize bushy stunt phytoplasma, and maize rayado fino virus.
Corn stunt disease can lead to stunted plants, leaf reddening, tillering (abnormal shoot development), and significant yield loss. Symptoms typically appear well after initial infection, often around 30 days after feeding, making early detection challenging.
Figure 1. Adult Corn Leafhopper
Photo: Ashleigh M. Faris, Oklahoma State University
Figure 2. Red, Stunted Corn with Corn Stunt
Photo: Maira R. Duffeck, Oklahoma State University
- The corn leafhopper or corn stunt disease have not been reported in North Carolina.
- There is no established threshold for corn leafhopper populations in the United States.
- Insecticide applications will not reverse infection or reduce disease incidence once plants are infected, as symptoms generally appear weeks after transmission has already occurred.
- Do not apply insecticide for this insect. After plants reach the V8 growth stage, new infections will not have enough time to affect yield.
Grower Action:
We encourage growers to scout fields carefully for corn leafhoppers and potential corn stunt symptoms. If you suspect its presence, please report it to your local Extension office. Gathering information on its distribution will help improve future management strategies.
Helpful Resources:
- Oklahoma State University Extension
- Texas A&M AgriLife Extension
- Crop Protection Network: Corn Leafhopper Map
- Corn Stunt: Identification, Distribution, and Management (YouTube)
- Henrique Pozebon, Glauber Renato Stürmer, Jonas André Arnemann. Corn Stunt Pathosystem and Its Leafhopper Vector in Brazil, Journal of Economic Entomology, Volume 115, Issue 6, December 2022, Pages 1817–1833, https://doi.org/10.1093/jee/toac147
Scout and report any suspected sightings to your local Extension office!