Plum fruit moth

Grapholita prunivora

1. Identification

• Common name: Plum moth
• Scientific name: Grapholita prunivora Walsh
• Order: Lepidoptera
• Family: Tortricidae

2. Pest description

• Pinkish caterpillars, with a brown head, which develop inside the fruits.
• Small adults, with brownish forewings and discreet patterns.
• Attacks mainly stone fruits, penetrating the interior to feed.
• Species present in temperate orchards, with relevant economic impact.

3. Main hosts

• Plum tree.
• Peach tree.
• Blackthorn.
• Apple tree.
• Pear tree.
• Other fruit-bearing rosaceous plants.

4. Symptoms and damage

• Perforations in the fruits and presence of exudates.
• Internal galleries with residues and excrement.
• Premature fruit drop.
• Reduced commercial quality.
• Significant damage to fruits destined for the fresh market.

5. Biological cycle

• One to two generations per year, depending on the climate.
• Eggs laid on the surface of the fruits or on nearby leaves.
• Caterpillars rapidly penetrate the fruit, where they complete their development.
• Pupation in the soil or in shelters in the bark of the trees.
• Adults emerge from spring to summer, with well-defined flight peaks.

6. Monitoring

• Observation of perforated fruits and those with internal residues.
• Opening of suspect fruits for detection of caterpillars.
• Monitoring with pheromone traps for flight detection.
• Assessment of the percentage of attacked fruits throughout the crop cycle.

7. Management measures

• Cultural: collection and destruction of fallen fruits, cleaning of the soil and adequate canopy management.
• Biological: conservation of natural parasitoids and use of Bacillus thuringiensis in early stages.
• Integrated protection: regular monitoring, interventions only when justified and judicious application of authorised insecticides.

Bibliographic references

• EPPO Global Database – Grapholita prunivora.
• CABI Invasive Species Compendium – G. prunivora.
• Alford, D. (2007). Pest management in fruit crops.
• Leskey, T. C., & Bergh, J. C. (2005). Biology and management of internal fruit feeders in stone fruits. Journal of Integrated Pest Management.
• Neven, L. G. (2015). Tortricid pests of temperate fruit crops. Annual Review of Entomology.