Submitted to: University of California Press-Cooperative Extension
Publication Type: Abstract Only
Publication Acceptance Date: March 17, 2005
Publication Date: March 17, 2005
Citation: Turechek, W. 2005. Xanthomonas in strawberry; past, present, and future. University of California Press-Cooperative Extension.
Angular leaf spot is caused by the bacterium Xanthomonas fragariae. The disease affects the foliage, often attacks the calyx, and cam move systemically within the plants vascular system to infect additional leaf tissue, crown tissue, and developing daughter plants. It is widely believed that the initial introduction of the pathogen in to production fields is through infected nursery stock. As a result, the EPPO (European and Mediterranean Plant Protection Organization) considers X. fragariae as an A2 quarantine pathogen (i.e., a pathogen absent from the majority of the strawberry-growing countries in Europe, but has the potential tro establish there). Nurseries wishing to export plants to European countries must maintain certain phytosanitary standards. Specifically, planting material must be derived from mother plants certified free of X. fragariae and production sites should be documented free from angular leaf spot for the past five growing seasons. In this talk, I will begin by reviewing the general biology and epidemiology of the pathogen, and then discuss current management practices, particularly how they apply to the California nursery industry. I will then emphasize the likely research activities that will be needed to move to a long-term solution to this near universal bacterial problem in the California strawberry nursery industry, highlighting activities conducted at the USDA-ARS Fruit Laboratory in Beltsville, MD.