Grape Tortrix

Argyrotaenia (=Tortix) ljungiana (=pulchellana)

1. Identification

• Common name: Grape tortrix
• Scientific name: Argyrotaenia ljungiana Thunberg
• Synonym: Tortrix pulchellana Haworth
• Order: Lepidoptera
• Family: Tortricidae

2. Pest description

• Yellowish-green caterpillars, very mobile, that roll up leaves with silken threads.
• Adults with brownish forewings with variable patterns and light hindwings.
• Attacks leaves, inflorescences and young berries.
• Polyphagous species, common in vineyards and various ornamentals.

3. Main hosts

• Grapevine.
• Apple.
• Pear.
• Strawberry.
• Various ornamentals and fruit trees.

4. Symptoms and damage

• Leaves rolled up and bound together with silken threads.
• Borings and consumption of the leaf blade.
• Damage to inflorescences and young berries.
• Flower drop and reduced fruit set.
• Production losses and reduced quality of the bunches.

5. Biological cycle

• Two to three generations per year in a mild climate.
• Eggs laid in clusters on leaves.
• Caterpillars develop through 5 instars.
• Pupation inside rolled-up leaves.
• Adults active from spring to autumn, with well-defined flight peaks.

6. Monitoring

• Observation of rolled-up leaves and presence of caterpillars.
• Inspection of damage to inflorescences and young berries.
• Monitoring with pheromone traps to detect flights.
• Assessment of the intensity of attack throughout the vegetative cycle.

7. Management measures

• Cultural: removal of attacked leaves and shoots, destruction of crop residues and improvement of canopy ventilation.
• Biological: use of Bacillus thuringiensis on young caterpillars and conservation of natural enemies.
• Integrated protection: monitoring with pheromones, interventions only when justified and judicious application of authorised insecticides.

Bibliographic references

• EPPO Global Database – Argyrotaenia ljungiana.
• CABI Invasive Species Compendium – A. ljungiana.
• Ioriatti, C., & Lucchi, A. (2016). Semiochemical strategies for tortricid control in vineyards. Journal of Pest Science.
• Witzgall, P., Kirsch, P., & Cork, A. (2010). Sex pheromones and their impact in pest management. Journal of Chemical Ecology.
• Alford, D. (2007). Pest management in fruit crops.