Potato Aphid

Macrosiphum euphorbiae

1. Identification

• Common name: Potato aphid / Green potato aphid.
• Scientific name: Macrosiphum euphorbiae Thomas
• Order: Hemiptera
• Family: Aphididae

2. Pest description

• Apterous adults: Elongated body, light green to yellowish‑green; long, dark siphunculi; clear, well‑developed cauda.
• Winged adults: Dark head and thorax; transparent wings; yellowish‑green abdomen.
• Nymphs: Similar to apterous adults, but smaller and lighter.

3. Main hosts

• Horticultural crops such as potato, tomato, pepper, eggplant and various solanaceous plants.
• It also occurs on various spontaneous species, including Euphorbia spp.

4. Symptoms and damage

• Curling and deformation of young leaves.
• Reduced vigour and delayed growth.
• Excretion of honeydew, favouring sooty mould.
• It can act as a vector of important viruses, including potato mosaic virus and leaf roll virus.

5. Biological cycle

• Species generally anholocyclic in temperate climate regions, reproducing by parthenogenesis during much of the year.
• Rapid development, with multiple generations per year.
• Populations increase in mild climate conditions and high host availability.

6. Monitoring

• Direct observation of the underside of the leaves and of the young shoots.
• Counting of individuals per leaf or per plant.
• Assessment of the presence of honeydew and of natural beneficials.

7. Management measures

• Cultural: Removal of heavily infested plants; management of spontaneous vegetation; avoid excess nitrogen.
• Biological: Conservation of beneficials such as Coccinellidae, Syrphidae and Aphidiinae parasitoids.
• Integrated protection: Intervention only when necessary; preference for selective products compatible with beneficials.

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.
• Radcliffe, E. B., & Ragsdale, D. W. (2002). “Aphid-transmitted potato viruses.” In: Potato Health Management. APS Press.
• Dixon, A. F. G. (1998). Aphid Ecology: An Optimization Approach. Chapman & Hall.