Leafhoppers

Leafhoppers (Empoasca spp., Macrostele spp., etc.) are small polyphagous insects of the order Hemiptera; they are 2 to 4 mm long and have a narrow body which is greenish and sometimes pink. The colour of the larvae, which are elongated, is white which subsequently turns light green. Larvae are wingless (photo 1) but adults may or may not have 2 pairs of wings. They usually winter on plants with persistent leaves, and the leafhoppers are found mainly in hot and warm temperate climates. These insects have 3 or 4 generations a year, with 5 moultings up to the adult stage.

The damage done by leafhoppers (photo 2) is caused by biting potato plant leaflets, which in turn causes necrosis and dehydration of the veins, followed by a lightening of the leaf blades, going from the edge to the centre of the leaflet, or locally at the biting points.

In Europe, the direct damage done by these insects to the potato is of minor importance. However, as virus or phytoplasma (stolbur) vectors, their damage may be more significant.