Tomato fruitworm

Helicoverpa armigera

1. Identification

• Common name: Tomato fruitworm
• Scientific name: Helicoverpa armigera Hübner
• Order: Lepidoptera
• Family: Noctuidae

2. Pest description

• Adults: Moths with a 30–40 mm wingspan, yellowish-brown forewings with irregular spots; whitish hindwings with a dark margin.
• Larvae: Very polymorphic, ranging from green to brown; body with light and dark longitudinal bands; brown head; extremely mobile and voracious.
• Pupae: Formed in the soil, in earthen chambers.
• Eggs: Singly or in small groups, generally on the underside of the leaves or on floral organs.

3. Main hosts

• Tomato, pepper, bean, chickpea, pea.
• Maize, cotton, tobacco, sunflower.
• Various vegetables and ornamentals.
• Highly polyphagous species, with more than 180 recorded hosts.

4. Symptoms and damage

• Perforations in young leaves and shoots.
• Severe damage to flowers and flower buds.
• Deep perforations in fruits (e.g.: tomato), with internal galleries and secondary rots.
• In maize, perforation of the whorl and damage to the cob.
• Significant production losses in intense attacks.

5. Biological cycle

• Several generations per year, with greater intensity in summer.
• Adults active during much of the year in mild climates.
• Eggs hatch in 2–5 days; caterpillars develop over 2–3 weeks.
• Pupation in the soil; adults emerge after 10–15 days.
• Development favoured by high temperatures and high availability of hosts.

6. Monitoring

• Observation of eggs and young caterpillars on leaves and flowers.
• Assessment of damage to flower buds and young fruits.
• Pheromone traps for detecting males and forecasting population peaks.
• Reinforced monitoring during hot, dry periods.

7. Management measures

• Cultural: Removal of damaged fruits; surface tillage of the soil to expose pupae; elimination of host weeds; crop rotation with less susceptible species.
• Biological: Use of authorised entomopathogenic microorganisms; application of microbial bioinsecticides; conservation of natural enemies through appropriate cultural practices.
• Integrated protection: Regular monitoring; intervention only when necessary; practices that reduce the survival of pupae in the soil and the availability of susceptible floral organs and fruits.

Bibliographic references

• EPPO Global Database – Helicoverpa armigera
• CABI Invasive Species Compendium – Helicoverpa armigera
• Fitt, G. P. (1989). The ecology of Helicoverpa armigera. Annual Review of Entomology, 34: 17–52.
• Zalucki, M. P. et al. (1994). Ecology and behavior of Helicoverpa armigera. Annual Review of Entomology, 39: 593–619.
• Capinera, J. L. (2001). Handbook of Vegetable Pests. Academic Press.
• Pogue, M. G. (2004). A review of the genus Helicoverpa. USDA Forest Service.