Author:
Burbank Lindsey,Sisterson Mark S.,Wei Wei,Ortega Brandon,Luna Nathaniel,Naegele Rachel
Abstract
AbstractManagement of widespread plant pathogens is challenging as climatic differences among crop growing regions may alter key aspects of pathogen spread and disease severity.Xylella fastidiosais a xylem-limited bacterial pathogen that is transmitted by xylem sap feeding insects. Geographic distribution ofX. fastidiosais limited by winter climate and vines infected withX. fastidiosacan recover from infection when held at cold temperatures. California has a long history of research on Pierce’s disease, and significant geographic and climatic diversity among grape-growing regions. This background in combination with experimental disease studies under controlled temperature conditions can inform risk assessment forX. fastidiosaspread and epidemic severity across different regions and under changing climate conditions. California’s grape growing regions have considerable differences in summer and winter climate. In northern and coastal regions, summers are mild and winters cool, conditions favoring winter recovery of infected vines. In contrast, in inland and southern areas summers are hot and winters mild, reducing likelihood of winter recovery. Here, winter recovery of three table grape cultivars (Flame, Scarlet Royal, and Thompson seedless) and three wine grape cultivars (Sauvignon Blanc, Cabernet Sauvignon, and Zinfandel) were evaluated under temperature conditions representative of the San Joaquin Valley, an area with hot summers and mild winters that has been severely impacted by Pierce’s disease, and contains a large portion of California grape production. Mechanically inoculated vines were held in the greenhouse under one of three warming treatments to represent different seasonal inoculation dates prior to being moved into a cold chamber. Winter recovery under all treatments was generally limited, but with some cultivar variation. Given hot summer temperatures of many grape-growing regions worldwide, as well as increasing global temperatures overall, winter recovery of grapevines should not be considered a key factor affectingX. fastidiosaspread and epidemic severity in the majority of cases.
Publisher
Cold Spring Harbor Laboratory