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Researchers find wasp can control spotted gum psyllid

The Issue

Researchers find wasp can control spotted gum psyllid
Psyllid1 — Adult Spotted gum eucalyptus psyllid. The white substance is the side of the lerp produced by an immature psyllid of sugar, wax, and excrement. It shelters the developing psyllid.
In August 2000, two psyllid species were discovered on lemon-scented gum and spotted gum trees in the Anaheim area. One is the spotted gum psyllid, a lerp psyllid, and another is the lemon gum psyllid. The insects cause leaf damage and drop which can stress trees and make them susceptible to fatal attack by other insects. Psyllids suck sap from leaves and produce a sticky substance called honeydew, which drops to the ground on cars and sidewalks.

What Has ANR Done?

With funding from the UC Exotic/Invasive Pests and Diseases Research Program, a successful biological control for the spotted gum psyllid has been found. After testing various species, one parasitoid, Psyllaephagus nr. Sp. hirtus, was found to be effective at controlling the spotted gum psyllid without destroying other beneficial species.

The Payoff

The next step is statewide biological control against spotted gum psyllid

Parasites have been released and have become established in many communities in California. In the coastal regions of the state, the parasite is starting to control the pest to the point where many infested trees will be saved. Biological controls such as this enable us to control pests without pesticides.

Contact

Supporting Unit:

Integrated Pest Management
 
Stephanie Klunk
Senior Writer
UC Statewide IPM Program
One Shields Avenue
Davis, CA 95616
(530) 754-6724