He liothis/Helicoverpa Problem in the Americas: Biology and Management

The com earworm, Helicoverpa zea (Boddie) and tobacco budworm, Heliothis virescens (Fabricius) occur throughout the temperate and tropical regions in the Americas. The com earworm, H. zea, is widely distributed in Canada (British Columbia, Manitoba, New Brunswick, Ontario, Quebec and Saskatchewan), Mexico and the USA (including Hawaii) in North America; and Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Falkland Islands, French Guiana, Guyana, Pern, Surinam, Umguay and Venezuela in South America. The tobacco budworm, H. virescens, is found throughout the eastern and southwestern United States, and also in California. It over-winters successfully only in the southern states. However, it occasionally survives in cold climates in greenhouses and other sheltered locations. Tobacco budworm disperses northward annually, and can be found in New England, New York, and southern Canada during late summer. It also occurs widely in the Caribbean, and sporadically in central and South America. In North America, H. zea is the second most important economic pest species (preceded only by codling moth) (Hardwick 1965). The estimated annual cost of damage by H. zea and H. virescens together on all crops in the USA is more than US$1000 million, despite an expenditure of US$ 250 million on insecticide application for controlling these pests (Fitt 1989).