How does the glassy-winged sharpshooter spread Pierces Disease?
Sharpshooters acquire the bacterium from infected plants and transmit it to healthy plants while feeding. The insect harbors the bacteria within its mouthparts. It only takes a few hours (sometimes only minutes) to acquire or transmit the disease. Thus, a healthy flying adult insect, that is moving around a vineyard, can theoretically transmit the disease to several plants a day. Juvenile stages of the sharpshooter loose the bacteria when they undergo a molt of the exoskeleton. They can readily re-acquire the bacteria by feeding on diseased plants. If the adult stage of the sharpshooter acquires the bacteria, the insect will harbor and be able to transmit the bacteria throughout its life (over 6 months). Once e a plant is infected with Pierce’s disease, the plant can act as a reservoir of the bacterium. Any sharpshooter that feeds on the infected portions of the plant can pass on the infection to other plants.
