Submitted to: Plant Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/1/2006
Publication Date: 12/20/2006
Citation: Koike, S.T., Kammeijer, K., Bull, C.T., O'Brien, R.D. 2006. First report of bacterial blight of cauliflower (Brassica oleracea var. botrytis) caused by Pseudomonas syringae pv. alisalensis in California. Plant Disease DOI:10.1094/PD-90-1551B. Interpretive Summary: Romanesca cauliflower (also called summer cauliflower) produces a commercial crop of green cauliflower heads in Monterey County California. Plant pathogens can limit the supply of this and other crucifers to the consumer and profits of the producers. The first step in reducing the impact of emerging plant diseases on crops is to identify the pathogen causing the disease. In this study we identified a novel disease of romanesca that has been affecting this crop since 2005 and showed that it is the same pathogen that causes bacterial blight on crucifers throughout the country. This information will be used by producers to make crop production choices that reduce the spread of the pathogen from one susceptible crop to another.
Technical Abstract: A novel bacterial blight commercial romanesca (green) cauliflower (Brassica oleracea var. botrytis) was seen for the first time in coastal California in 2005. Koch’s postulates were completed and the etiology of the pathogen was determined. Characterization showed that pathogen was Pseudomonas syringae pv. alisalensis. This is the first report of P. syringae pv. alisalensis causing a disease on commercially grown romanesca. This research expands the known host range of this pathogen.