Western Corn Rootworm
Diabrotica virgifera virgifera
high risk
insect
Overview
The most economically important corn pest in the United States. Costs over $1 billion annually in losses and control.
Adults 6mm, yellow-green with black stripes. Larvae (rootworms) white, slender, to 15mm in corn roots.
Prevention Strategies
- •Crop rotation - larvae starve in non-corn fields
- •Bt corn hybrids with rootworm resistance
- •Monitoring adult populations with traps
Control Methods
- •Crop rotation most effective (larvae die without corn)
- •Soil insecticide at planting (restricted use)
- •Seed treatments with neonicotinoids
- •Bt transgenic corn (widespread use but resistance developing)
Interesting Facts
- •Has evolved resistance to crop rotation in some populations (females now lay eggs in soybean fields)
- •Has evolved resistance to Bt corn in some populations within 5-10 years of GMO adoption
- •One of the most studied insects in agricultural science
- •Introduced accidentally to Europe in airport cargo from US and continues to spread