Thrips

Thysanoptera (Thrips - various genera)

1. Identification

• Common name: Thrips
• Scientific name: Thysanoptera (various genera, including Frankliniella spp., Thrips spp., Echinothrips spp., Haplothrips spp.)
• Order: Thysanoptera
• Family: Various (Thripidae, Phlaeothripidae, among others)

2. Pest description

• Very small insects (1–2 mm), with a narrow, elongated body.
• Narrow wings with long fringes, a distinctive characteristic of the order.
• Nymphs of yellowish to brownish coloration, generally found on the underside of the leaves or in the flowers.
• They feed by rasping plant tissues and sucking the cell contents.
• Some species are vectors of important viruses, such as TSWV.

3. Main hosts

• Vegetables (tomato, pepper, cucumber, bean, onion).
• Fruit crops (grapevine, citrus).
• Ornamentals (chrysanthemum, gerbera, rose).
• A great diversity of spontaneous plants that act as a reservoir.

4. Symptoms and damage

• Silvering of the leaves due to the destruction of the epidermal cells.
• Black spots (excrement) on the leaf surface.
• Deformations in young leaves and flowers.
• Scars and blemishes on fruits, reducing their commercial value.
• Transmission of viruses, especially in horticultural crops.

5. Biological cycle

• Eggs inserted into the plant tissues.
• Nymphs feed actively on the leaves and flowers.
• Pre‑pupa and pupa generally in the soil or in plant debris.
• Rapid cycle in hot, dry conditions, favouring multiple generations per year.
• Populations increase significantly in greenhouses.

6. Monitoring

• Direct observation of symptoms and the presence of insects.
• Blue or yellow sticky traps for detection and counting.
• Sampling of flowers and young leaves.
• Reinforced monitoring during hot, dry periods or in greenhouses.

7. Management measures

• Cultural: removal of infested plants; control of spontaneous plants; adequate ventilation in greenhouses.
• Preventive: use of pest‑free plants; insect‑proof nets; strict cultural hygiene.
• Biological: use of predatory mites (Amblyseius swirskii, A. cucumeris) and predatory bugs (Orius spp.).
• Integrated protection: judicious application of authorised insecticides; rotation of modes of action; integration with biological control.

Bibliographic references

• EPPO Global Database – Thysanoptera.
• CABI – Invasive Species Compendium – Frankliniella occidentalis.
• Kirk, W. D. J. (1997). Feeding behaviour and nutritional requirements of thrips. In: Thrips as Crop Pests.
• Reitz, S. R. (2009). Biology and ecology of the western flower thrips. Annual Review of Entomology.
• Mound, L. A. & Teulon, D. A. J. (1995). Thysanoptera as phytophagous pests. Annual Review of Entomology.