Apple maggot

Rhagoletis pomonella

1. Identification

• Common name: Apple maggot fly
• Scientific name: Rhagoletis pomonella Walsh
• Order: Diptera
• Family: Tephritidae

2. Pest description

• Adults 4–5 mm, glossy black body with white markings.
• Wings with a characteristic pattern of dark bands.
• White larvae, apodous, develop inside the fruits.
• Brown pupae, formed in the soil.
• Eggs laid beneath the apple epidermis.

3. Main hosts

• Apple tree.
• Wild species of Malus.
• It may also attack pear trees and other Rosaceae, although less frequently.

4. Symptoms and damage

• Small egg-laying mark on the fruit epidermis.
• Soft, browned pulp with larval galleries.
• Deformed fruits or premature fruit drop.
• Total loss of commercial value in infested fruits.
• Facilitation of secondary infections by fungi.

5. Biological cycle

• One generation per year.
• Adults emerge in summer, generally between June and August.
• Oviposition in fruits at the start of ripening.
• Larvae feed for 2–3 weeks.
• Pupation in the soil, where they overwinter.
• Emergence synchronised with fruit development.

6. Monitoring

• Yellow chromotropic traps with specific attractants.
• Weekly counting of captured adults.
• Observation of symptoms on the fruits.
• Fruit sampling for larva detection.
• Intensive monitoring between June and September.

7. Management measures

• Cultural: collection and destruction of infested fruits; superficial soil tillage to expose pupae; early harvesting in sensitive varieties.
• Biological: conservation of natural parasitoids; application of entomopathogenic nematodes to the soil.
• Integrated protection: continuous monitoring; targeted treatments when thresholds are reached; use of mass-trapping traps; judicious application of authorised insecticides; proper orchard management to reduce pupation sites.

Bibliographic references

• EPPO Global Database – Rhagoletis pomonella.
• CABI Invasive Species Compendium – Rhagoletis pomonella.
• Prokopy, R. J. & Papaj, D. R. (2000). Ecology and behavior of apple maggot fly.
• Neilson, W. T. A. (1988). Biology and management of Rhagoletis spp..