Potato Leafhopper
Beginner
Scientific Name
Empoasca fabae
Identification
- Both adults and nymphs are long and narrow in shape, abdomens tapered.
- Older nymphs develop wingpads on the thorax.
- Nymphs are light green, 1-3 mm long, and walk sideways across the leaf when disturbed.
- The adults are green, about 3 mm long (1/8 in), with long folded wings, fly away quickly.
- Leafhoppers suck sap from the leaves, which causes yellow mottling around the edges.
- They also inject a toxin into the plant while they feed which reduces shoot vigour.
- Affected leaves turn pale green and curl downward at the margins.
Often Confused With
Aphids
Tarnished plant bugs
Herbicide injury (Sinbar)
Period of Activity
Potato leafhoppers overwinter in the southern United States and are carried northwards on air currents. They migrate into new plantings of strawberries in early or mid June, often after the first cut of hay. Multiple generations are active throughout the summer and early fall.
Scouting Notes
Focus on new (first year) plantings. Examine new leaves for leaf curl and yellowing. Look for leafhopper nymphs on the underside of the leaf. Governor Simcoe and Jewel are good varieties to check for first signs of damage.
Thresholds
There are no thresholds established for potato leafhopper. Consider control if there are one or two nymphs per leaf and leaf curl is evident.
Advanced
Scientific Name
Empoasca fabae
Identification
Both adults and nymphs are long and narrow in shape, tapering at the end of the abdomen. Adults are 3 mm (1/8 in.) long, green with long folded wings. They fly away rapidly when disturbed. Nymphs are smaller than adults and walk sideways across the leaf when disturbed. Nymphs progress through 5 instars and turn from whitish-green to lime green and develop wingpads.
Leafhoppers suck sap from the leaves, and also inject a toxin into the plant while they feed. This toxin blocks the movement of water and nutrients to the affected areas and reduces shoot vigour. Affected leaves turn pale green or yellow. Discolouration is most evident at the tip and edges of the leaf, which usually curl downward at the margins.
Often Confused With
Sinbar Damage (Potato leafhopper injury and Sinbar damage can both cause leaf yellowing. Leafhopper injury always extends from the tip of the leaf along the edges. Sinbar damage is variable, can be interveinal, or veinal yellowing, and is never more pronounced at the tip.)
Aphids (Aphids are slow moving and have cornicles at the end of the abdomen. Leafhoppers move quickly and can scuttle sideways; the last abdominal segment is tapered.)
Tarnished plant bugs (Tarnished plant bug nymphs move more quickly, at least in warm weather, and the end of their abdominal segment is rounded without cornicles.)
Distinguishing Big Nymphs | ||||
Shape | Can be found* | Antennae | Movement | |
Aphids | Rounded abdomen with cornicles | Underside of new growth | Point forward or back, depending on species | Sluggish, slow moving |
Tarnished Plant Bugs | Rounded abdomen no cornicles | Blossom clusters | Point forward, very active | Move rapidly (when weather is warm) |
Leafhopper | Tapered abdomen, no cornicles | Underside of new growth | Point backwards | Move rapidly when prodded and weather is warm. Only nymphs to scuttle sideways. |
* All of these nymphs can be found in tapping trays
Biology
Potato leafhoppers are a pest to many crops other than strawberries, including alfalfa, beans, hay and raspberries. Adults lay eggs in the petiole of the host plant. Nymphs develop shortly after. Leafhoppers pass through 5 instars as they develop. They are found mostly on the underside of younger, fully expanded leaves. Sometimes the white empty skins from the previous instars can be found on the underside of leaves.
Period of Activity
Potato leafhoppers do not overwinter in Ontario; adults are transported to Ontario in the spring by wind currents from the southern United States. Potato leafhoppers migrate into new plantings of strawberries in early or mid June, often after the first cut of hay. Multiple generations are active throughout the summer and early fall.
Scouting Notes
Concentrate on monitoring first year (new) plantings. Begin monitoring in late June and continue through to August. Examine new leaves for leaf curl and yellowing. Look for leafhopper nymphs on the underside of the leaf.
Thresholds
There are no established thresholds for potato leafhopper. Consider control if there are one or two nymphs per leaf and leaf curl is evident.
Management Notes
- New plantings and certain cultivars, such as Governor, Simcoe, Jewel, are more susceptible to potato leafhopper injury.
- Fields near alfalfa or beans are at a higher risk.
- Control is usually only required in new plantings. Several sprays may be required.
- Spray for nymphs, not adults, when damage is evident.
- Control weeds and volunteer legumes in and around the planting.