ARS | Publication request: CHARACTERIZATION OF THE BACTERIAL LEAF SPOT PATHOGEN PSEUDOMONAS SYRINGAE PV MACULICOLA FROM FIELD OUTBREAKS IN SOUTH CAROLINA

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: May 18, 2006
Publication Date: July 1, 2006
Citation: Wechter, W.P., Keinath, A.P., Smith, J.P. 2006. Characterization of the bacterial leaf spot pathogen Pseudomonas syringae pv maculicola from field outbreaks in South Carolina. Phytopathology 96:S121.

Technical Abstract: South Carolina is one of the top five producers of leafy brassica vegetables in the United States with nearly 1600 hectares planted annually. In 2001, a leaf spotting disease was noted in a field in the principal production area for leafy greens in SC. Since this time, the disease has become more widespread and quite severe, resulting in losses of $1M per year in a single county. The causal agent of the disease was determined to be Pseudomonas syringae pv maculicola. Forty-five pathogenic isolates were collected from the major production areas of the state. These isolates were characterized using traditional bacteriology and biochemical techniques (i.e. LOPAT, coronatine production, and fatty acid methyl ester profiles) as well as DNA-based analysis (i.e. PCR-based coronatine gene detection, 16S sequence analysis, and rep-PCR fingerprint comparisons using the BOXA1R primer) and host range inoculation studies using turnip, tomato, collard, cabbage, and cauliflower. Data from these analyses indicate that the majority of the isolates are highly homologous yet distinct from a selection of strains from other areas of the United States.