Corn Earworm, Helicoverpa zea
(Lepidoptera: Noctuidae)

The corn earworm is found throughout the United States. Seven generations per year have been recorded, although four to five is more common. Eggs are usually laid on leaf hairs or the corn silks. As eggs hatch larvae may initially feed together but become cannibalistic as they grow. This is why a small number of larvae are found in an ear of corn. The larvae vary in color. The head may be orange or brown and the body may be brown, pink, yellow, and mostly black or a combination of more than one color. The body also has microspines that give the larvae a rough feel. The pupa can be found in the soil and is mahogany brown. The adult is also variable in color. The forewing of the moth is usually yellowish-brown in color and will have a central dark spot. This dark spot is most readily observed when the wing is viewed from below. The hind wing is creamy white.

The corn earworm insect is a serious pest in sweet corn production but attacks a wide range of crops. As a result, it is also known as the tomato fruitworm, sorghum headworm, vetchworm, and cotton bollworm. Corn and sorghum are the most favorable hosts but most vegetable crops are in the host range. Natural enemies exist but do not provide adequate control of the corn earworm. Cultural control practices include planting trap crops and using resistant host plants. Some varieties of corn are available that have the Bacillus thuringiensis toxin as a source of resistance. Chemical control is also used but resistance has been found to many pesticides.

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Corn earworm, Heliothis zea, mature larva, feeding on
foliage. This brown form is characteristic of this
insect, though other colors occur.
(Photographer: L. Buss, University of Florida)

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Corn earworm, Heliothis zea, adult (moth).
(Photographer: J. Capinera, University of Florida)

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Corn earworm, Heliothis zea, mature larva, feeding on
foliage. Color is quite variable, and this green form, while not
rare, is less common than the brown forms.
(Photographer: L. Buss, University of Florida)

Click to access Display and Print quality images.


Corn earworm, Heliothis zea, mature larva, feeding on ear
of corn.
(Photographer: J. Capinera, University of Florida)

Click to access Display and Print quality images.



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