In Ontario, the potato aphid is the first to infest the crop in the growing season. It is also the largest aphid that infests potatoes in the province. This aphid is usually found on the middle and upper leaves of potato plants.
High populations will cause wilting and will cover the upper leaves with sticky honeydew.
Identification
Wingless forms. They have elongated, wedge-shaped, yellow-green or pink bodies with long legs and long, slender cornicles. Their length ranges from 2.5–3.5 mm. The antennal tubercles slope outwards.
Winged forms. They are approximately 2.5–3.5 mm long. The antennal tubercles slope outward. The head and thorax are light yellow-brown or green-brown to dark brown. The abdomen is green or sometimes pink. The darker, pigmented legs and antennae are a distinctive feature of the potato aphid.
