Phytoplasma can infect apple, pear and apricot trees. Especially on high stem trees, phytoplasma are spread diffusely in Switzerland. They are transmitted during grafting and spread by psyllids. To assure healthy planting material, fruit tree phytoplasma are declared quarantine pests and are subject to the plant passport.
Unlike in control of fire blight, no plant protection product is effective against phytoplasma. To reduce the risk of infection, it is necessary to plant healthy trees and to eliminate infected trees near and inside orchards. Pesticides against psyllids is neither helpful nor registered because the disease is transmitted by adult immigrants.