Cabbage aphid

Brevicoryne brassicae

1. Identification

• Common name: Cabbage aphid / Mealy cabbage aphid.
• Scientific name: Brevicoryne brassicae L.
• Order: Hemiptera
• Family: Aphididae

2. Pest description

• Apterous adults: Oval body, greyish‑green, covered by a whitish waxy layer; short, dark siphunculi; short cauda.
• Winged adults: Dark head and thorax; transparent wings; greyish‑green abdomen with less waxy deposit.
• Nymphs: Similar to apterous adults, but smaller and with a smaller amount of wax.

3. Main hosts

• Plants of the Brassicaceae family, including cabbage, broccoli, cauliflower, turnip, radish and rapeseed.
• It may occur on spontaneous species of the same family.

4. Symptoms and damage

• Dense colonies on the underside of the leaves and on the stems.
• Curling and yellowing of the leaves.
• Reduced growth and loss of vigour.
• Excretion of honeydew, favouring sooty mould.
• It can significantly reduce the productivity and commercial quality of the crops.
• Potential vector of viruses affecting crucifers.

5. Biological cycle

• Species generally anholocyclic in temperate climates, reproducing by parthenogenesis during much of the year.
• Multiple generations per year, with rapid development in mild climate conditions.
• Colonies can grow rapidly due to the high reproductive rate.
• It often overwinters as a nymph on woody or persistent herbaceous hosts.

6. Monitoring

• Direct observation of the underside of the leaves and of the stems.
• Counting of individuals per plant or per leaf.
• Assessment of the presence of honeydew and of natural beneficials.
• Frequent monitoring is essential due to the rapid population growth.

7. Management measures

• Cultural: Removal of heavily infested plants; crop rotation; control of spontaneous crucifers; avoid excess nitrogen.
• Biological: Conservation of beneficials such as Coccinellidae, Syrphidae, Chrysopidae and Aphidiinae parasitoids.
• Integrated protection: Intervention only when necessary; preference for selective products compatible with beneficials; special attention to the early stages of the crop.

Bibliographic references

• Blackman, R. L., & Eastop, V. F. (2000). Aphids on the World’s Crops: An Identification and Information Guide. Wiley.
• van Emden, H. F., & Harrington, R. (2017). Aphids as Crop Pests (2nd ed.). CABI.
• Dixon, A. F. G. (1998). Aphid Ecology: An Optimization Approach. Chapman & Hall.
• Bartholomew, J. (1999). “Aphids on Brassica Crops.” In: Insect Pests of Vegetables. CRC Press.