Wireworms

Agriotes spp.

1. Identification

• Common name: Wireworms, click beetle larvae
• Scientific name: Agriotes spp.
• Species of greatest agronomic importance (e.g.: Agriotes lineatus L., Agriotes obscurus L., Agriotes sputator L., Agriotes ustulatus Schäller)
• Order: Coleoptera
• Family: Elateridae

2. Pest description

• Adults: Elongated beetles, brown to brownish; rigid body; able to “click” when turned on their backs.
• Larvae (wireworms): Cylindrical body, rigid and shiny; yellowish‑brown coloration; dark head; up to 25 mm in length.
• Pupae: Develop in the soil, in shallow chambers.

3. Main hosts

• Vegetable crops (potato, carrot, onion, beet).
• Maize and other cereals.
• Nurseries and sensitive young crops in the soil.
• Various spontaneous plants and grasses that favour the maintenance of populations.

4. Symptoms and damage

• Deep perforations in tubers and roots.
• Internal damage to potato, reducing commercial value.
• Cutting or destruction of young seedlings at the collar level.
• Stand reduction in direct‑seeded crops.
• More severe damage in soils with high organic matter or after fallow with dense vegetation.

5. Biological cycle

• Multi‑year cycle, generally 3 to 5 years.
• Adults emerge in spring and lay eggs in the soil.
• Larvae remain in the soil for several years, feeding on roots and underground tissues.
• Pupation occurs in summer, with adults emerging the following year.
• Populations favoured by moist soils, rich in organic matter and with the presence of grasses.

6. Monitoring

• Pheromone traps for capturing adults.
• Soil sampling for detection of larvae.
• Observation of emergence failures and cutting symptoms in seedlings.
• Historical record of plots with recurring incidence.

7. Management measures

• Cultural: Crop rotation; avoid sowing in soils with a high history; surface tillage to expose larvae; management of weeds and grasses.
• Biological: Promotion of natural soil predators (ground beetles, rove beetles).
• Integrated protection: Use of baits for risk assessment; intervention only when population levels justify it; preference for selective methods compatible with beneficials.

Bibliographic references

• Furlan, L. (2004). The biology of Agriotes spp. and implications for integrated pest management. IOBC/WPRS.
• EPPO Global Database – Agriotes spp.
• CABI Invasive Species Compendium – Agriotes spp.
• Vernon, R. S., & van Herk, W. G. (2013). Wireworms as pests of potato. American Journal of Potato Research.
• Parker, W. E., & Howard, J. J. (2001). The biology and management of wireworms. Agricultural Zoology Reviews.
• Furlan, L., & Tóth, M. (2007). Monitoring of Agriotes species with pheromone traps. Journal of Applied Entomology.