It can also survive in several hosts where symptoms are not produced. Pierce's disease is a common disease in many grape-growing areas but severe losses are confined to isolated host spots. The pathogen is transmitted by several species of sharpshooter leafhoppers and can be found throughout the Americas where winter conditions are mild. Moderate winter temperatures contribute to the survival of both the insect vector and reservoir host plants. The successful relationship between the pathogen and its vector has to do with the feeding habits of the leafhoppers.
Sharpshooters feed specifically on the sap found in host xylem tissue.
Contaminated sap is transmitted from plant to plant when they feed. Once X. fastidiosa is introduced into host xylem it multiplies and produces gums and tyloses that plug the water-conducting vessels. The bacterium also produces a phytotoxin responsible for some host symptoms. Symptoms Leaf scorch is one of the most common symptoms observed on plants infected with Xyllela fastidiosa . Scorching typically begins on the outer margin and moves inward.