Vegetable leafminer

Liriomyza sativae

1. Identification

• Common name: Vegetable leafminer
• Scientific name: Liriomyza sativae Blanchard
• Order: Diptera
• Family: Agromyzidae

2. Pest description

• Adults: small flies of 1.3–2.3 mm; greyish-yellow body; transparent wings; females with an ovipositor adapted for leaf perforation.
• Larvae: legless, pale yellow in colour; develop inside the leaves, forming serpentine mines.
• Pupae: form in the soil or occasionally on the leaf itself; brown colouration.
• Eggs: deposited individually in the leaf tissue, generally on the upper surface.

3. Main hosts

• Vegetables: tomato, pepper, bean, cucumber, melon, courgette, lettuce, onion.
• Ornamentals: chrysanthemum, gerbera, carnation, petunia.
• Other cultivated and spontaneous dicotyledons may serve as reservoirs.

4. Symptoms and damage

• Serpentine, irregular mines on the leaves, resulting from larval feeding.
• Pinpoint perforations caused by the females during oviposition and feeding.
• Necrosis of the mined areas and partial drying of the leaf.
• Reduced photosynthetic capacity and plant vigour.
• In severe attacks, significant defoliation and yield loss.
• Greater susceptibility to secondary infestations due to the perforations.

5. Biological cycle

• Rapid cycle, which can be completed in 2–3 weeks under favourable conditions.
• Eggs hatch within a few days; larvae develop through 3 instars inside the mine.
• Pupation in the soil or on the leaf surface.
• Adults emerge throughout the year in greenhouses; outdoors, peaks in spring and summer.
• High reproductive capacity and several generations per year.

6. Monitoring

• Direct observation of recent mines and leaf perforations.
• Counting of mined leaves on representative plants.
• Yellow chromotropic traps for adult detection.
• Regular monitoring in greenhouses, where the pest develops more rapidly.

7. Management measures

• Cultural: removal of heavily attacked leaves, elimination of spontaneous host plants and proper management of greenhouse ventilation.
• Biological: conservation of natural parasitoids (e.g.: Diglyphus isaea, Dacnusa sibirica) and use of authorised bioinsecticides on young larvae.
• Integrated protection: continuous monitoring, intervention only when necessary, rotation of modes of action and practices that reduce larval and pupal survival.

Bibliographic references

• EPPO Global Database – Liriomyza sativae.
• CABI Invasive Species Compendium – Liriomyza sativae.
• Parrella, M. P. (1987). Biology of Liriomyza species. Annual Review of Entomology, 32, 201–224.
• Weintraub, P. G., & Horowitz, A. R. (1995). The newest leafminer pest in Israel: Liriomyza sativae. Phytoparasitica, 23, 177–184.
• Spencer, K. A. (1973). Agromyzidae (Diptera) of Economic Importance. Dr. W. Junk Publishers.