Whiteflies

Trialeurodes vaporariorum and Bemisia tabaci

1. Identification

• Common name: Whiteflies
• Scientific name: Trialeurodes vaporariorum Westwood and Bemisia tabaci Gennadius
• Order: Hemiptera
• Family: Aleyrodidae

2. Pest description

• Small adults (1–2 mm), pale body and powdery white wings.
• Flattened nymphs, greenish or translucent, fixed on the underside of the leaves.
• Oval eggs, deposited in circles or groups on the underside.
• Abundant production of honeydew, favoring the development of sooty mold.
• Rapid cycle under greenhouse conditions or in warm climates.

3. Main hosts

• Vegetables: tomato, cucumber, pepper, zucchini, bean.
• Ornamentals: gerbera, poinsettia, chrysanthemum.
• Fruit trees and various crops: citrus, strawberry, potato.
• Wide range of hosts, especially in protected environments.

4. Symptoms and damage

• Yellowing and curling of the leaves.
• Reduced vigor and delayed growth.
• Abundant honeydew and development of sooty mold.
• Transmission of viruses (particularly by B. tabaci).
• Significant reduction in productivity and commercial quality.

5. Biological cycle

• Rapid development at high temperatures.
• Eggs → nymphs (several instars) → pupa → adult.
• Complete cycle in 18–30 days, depending on temperature.
• Multiple annual generations, continuous in the greenhouse.
• Adults with high mobility and dispersal capacity.

6. Monitoring

• Yellow and blue chromotropic traps for detection and population tracking.
• Observation of the underside of the leaves to identify eggs and nymphs.
• Assessment of the presence of honeydew and sooty mold.
• Frequent monitoring in greenhouses and sensitive crops.
• Recording of environmental conditions favorable to development.

7. Management measures

• Cultural: removal of infested leaves, elimination of crop residues, control of spontaneous host plants and adequate ventilation in greenhouses.
• Biological: use of natural enemies such as Encarsia formosa, Eretmocerus eremicus and predators such as Macrolophus pygmaeus and Nesidiocoris tenuis.
• Integrated protection: continuous monitoring, yellow traps, judicious application of authorized insecticides, rotation of modes of action and integration with biological control to avoid resistance.

Bibliographic references

• EPPO Global Database – Trialeurodes vaporariorum and Bemisia tabaci.
• CABI Invasive Species Compendium – T. vaporariorum and B. tabaci.
• Byrne, D. N. et al. (1990). Biology and ecology of whiteflies.
• Oliveira, M. R. V. et al. (2001). The worldwide spread of Bemisia tabaci.