Submitted to: American Phytopathological Society
Publication Type: Proceedings
Publication Acceptance Date: 3/20/2006
Publication Date: 10/2/2006
Citation: Bull, C.T., Koike, S.T. 2006. Emergence of bacterial blight of crucifers in California and the U.S. Proceedings of the APS-Pacific Division Meeting. Boise, Idaho, June 2006. No page number. Interpretive Summary: N/A
Technical Abstract: Since its initial appearance in 1995 on broccoli raab (Brassica rapa subsp. rapa) in the Salinas Valley of California, Pseudomonas syringae pv. alisalensis has been shown to cause bacterial blights on a variety of crucifers in California and other states. In addition to published reports of outbreaks in commercial field plantings of broccoli raab, broccoli (Brassica oleracea subsp. botrytis) and arugula (Eruca sativa) it has recently caused disease on conventionally and organically produced nursery transplants and other crops in the field. The 2005 outbreak of bacterial blight on crucifer transplants may have been due to the development of resistance to copper used for disease control. All strains of P. syringae pv. alisalensis isolated from diseased transplants from this outbreak were resistant to at least 100 µg/ml copper. It is likely that bacterial blight of crucifers is more widespread than currently reported and may occasionally be misidentified as P. syringae pv. maculicola though these organisms can readily be differentiated.