Oriental Fruit Moth

Grapholita (=Cydia) molesta

1. Identification

• Common name: Oriental peach moth
• Scientific name: Grapholita molesta Busck
• Synonym: Cydia molesta Busck
• Order: Lepidoptera
• Family: Tortricidae

2. Pest description

• Caterpillars pinkish to cream in colour, with a brown head; they reach about 10–12 mm.
• Small adults, with brownish forewings bearing discreet patterns; greyish hindwings.
• A borer species of shoots and fruits, with major economic impact on stone and pome fruits.
• Young caterpillars penetrate the shoots, causing wilting and death of the apices.
• In later stages, they bore into fruits, causing internal galleries and significant commercial losses.

3. Main hosts

• Peach and nectarine.
• Plum.
• Apple.
• Pear.
• Other occasional hosts within the Rosaceae.

4. Symptoms and damage

• Young shoots wilted and dried out due to larval penetration.
• Borings in the fruits, with internal galleries and excrement.
• Premature fruit drop.
• Deformations and loss of commercial quality.
• Severe damage in stone fruit orchards, especially early in the season.

5. Biological cycle

• Eggs laid singly on leaves, branches or fruits.
• Caterpillars develop inside shoots or fruits.
• Pupation occurs in silken cocoons on the bark, soil or orchard structures.
• Adults emerge throughout spring and summer.
• Several generations per year, strongly dependent on temperature.

6. Monitoring

• Pheromone traps to capture males and determine the start of flight.
• Observation of wilted and bored shoots.
• Inspection of young fruits to detect borings.
• Regular sampling from the start of spring.

7. Management measures

• Cultural: removal of infested shoots; destruction of fallen fruits; improvement of air circulation in the orchard.
• Preventive: intensive monitoring from the start of the season; management of alternative hosts.
• Biological: mating disruption; use of Bacillus thuringiensis in young stages; promotion of natural parasitic insects / organisms .
• Integrated protection: judicious application of authorised insecticides based on thresholds and flight curves; integration of cultural, biological and chemical measures.

Bibliographic references

• EPPO Global Database – Grapholita molesta.
• CABI – Invasive Species Compendium – Grapholita molesta.
• Riedl, H. et al. (1998). Integrated pest management of pome and stone fruits. UC ANR.
• Barnes, M. M. (1991). Tortricids in orchard ecosystems. CRC Press.