Recovery Plan for X-Disease in Stone Fruit Caused by ‘Candidatus Phytoplasma pruni’

Abstract

Stone fruits are a multibillion-dollar industry for the United States and Canada, one that has repeatedly suffered significant economic losses due to outbreaks of the X-disease phytoplasma (‘ Candidatus Phytoplasma pruni’) over the last century. Orchards and entire production areas have been abandoned, with corresponding losses to growers, fruit packers, and consumers. The most recent outbreak, in the U.S. Pacific Northwest, resulted in an estimated $65 million (USD) loss in revenue between 2015 and 2020 and is only increasing in incidence. Already present across much of the continental United States and Canada, the phytoplasma has a broad host range beyond stone fruit and is transmitted by at least eight leafhopper species, therefore stone fruit production in every state is at significant risk. This recovery plan was produced as part of the National Plant Disease Recovery System and is intended to provide a review of pathogen biology, assess the status of critical recovery components, and identify disease management research, extension, and education needs.