Peach Twig Borer

Anarsia lineatella

1. Identification

• Common name: Peach twig borer
• Scientific name: Anarsia lineatella Zeller
• Order: Lepidoptera
• Family: Gelechiidae

2. Description of the pest

• Adults: Small moths (≈ 12–16 mm wingspan); greyish forewings with dark spots; hindwings paler and fringed.
• Larvae: Brownish to pinkish caterpillars, with a dark head; up to 12–15 mm long; very active and aggressive when disturbed.
• Eggs: Isolated, whitish, laid on the bark of the branches or near the buds.

3. Main hosts

• Peach.
• Plum.
• Apricot.
• Almond.
• Other Prunus of lesser importance.

4. Symptoms and damage

• Perforation of buds and young shoots, leading to their wilting and death.
• Dry terminal branches (“dry strikes”).
• Superficial perforations and galleries in the fruit, especially near the stalk.
• Premature fruit drop and loss of commercial quality.

5. Biological cycle

• Overwinters as a young larva in shelters in the bark or in the buds.
• Activity begins in spring with the perforation of the shoots.
• Adults emerge in late spring and summer.
• Females lay eggs on the young branches and fruit.
• 2 to 3 generations per year, depending on climatic conditions.

6. Monitoring

• Observation of wilted and perforated shoots in early spring.
• Opening of terminal branches to detect larvae.
• Pheromone traps for the detection and tracking of flights.
• Assessment of fruit damage near the stalk.

7. Management measures

• Cultural: Pruning and destruction of infested branches; removal of damaged fruit; improvement of canopy ventilation.
• Biological: Conservation of natural beneficials (parasitoids of eggs and larvae).
• Integrated protection: Intervention based on pheromone monitoring; synchronisation of treatments with the start of larval hatching; preference for selective products compatible with beneficials.

Bibliographic references

• EPPO Global Database – Anarsia lineatella.
• CABI Invasive Species Compendium – Anarsia lineatella.
• Alford, D. V. (2007). Pest and Disease Management Handbook.
• Riedl, H. et al. (1998). Peach twig borer biology and management.