Norvartis researchers engineered the corn to carry a toxin-making gene from Bacillus thuringiensis bacteria. Norvartis licensed this gene from Monsanto Company. The Bt toxin serves as a natural insecticide in the corn plant's leaves, husk, silks and other parts where the caterpillar pests feed. The toxin doesn't harm humans, livestock, beneficial insects or other animals. But caterpillars that consume the toxin either stop eating or die.
Studies show earworms are more susceptible than fall armyworms.
Most armyworms survived but didn't reach their normal size. ARS scientists plan field studies to see how much less insecticide is needed when a Bt corn crop is planted. With DeKalb Genetics Corp., DeKalb, IL, to evaluate corn hybrids that possess both natural and bioengineered sources of genetic resistance to the fall armyworm. The fall armyworm is a serious pest of corn, especially late-planted corn in the South. New commercial hybrids with greater resistance to the pests could reduce farmers' production costs and increase profits.