Leafhoppers/Jassids
Lucere leafhopper - Austroasca alfalfae, Vegetable leafhopper - Austroasca viridigrisea
Pest Status: The lucerne leafhopper is a moderate pest. Despite its widespread abundance, the vegetable leafhopper (jassid) is only a very minor pest.
Damage
- Both the adults and nymphs are sap suckers.
- Lucerne leafhoppers are phloem feeders and inject a toxin, causing leaves to turn yellow and burn off (die) from the tips. These symptoms are called ´hopper burn´.
- Vegetable leafhoppers are xylem feeders and their feeding causes lots of small white spots (from dead cells) on leaves. The resultant feeding patterns are known as ´stippling´.
- Severe infestations of the lucerne jassid can stunt plant growth and reduce yield, but even high vegetable jassid populations have negligible if any effect on yield.
- Damage is worse when plants are stressed.
Monitoring and control
- Sample weekly at vegetative, flowering and pegging stages.
- Sample five leaves halfway up plants at six locations over the paddock for lucerne leafhoppers, and use a sweep net for vegetable leafhoppers.
- Use chemical control if more than 20% of leaves are affected with hopper burn.
- Only control vegetable leafhoppers if more than 25 hoppers per single sweep over a single row (90 cm spacing).
- For current chemical control options see Pest Genie or APVMA.
