Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 3/20/2011
Publication Date: 6/1/2011
Citation: Carey, A.B., Pusey, P.L., Smith, T., Loper, J.E., Stockwell, V. 2011. Plasmid content of Erwinia amylovora in orchards in Washington and Oregon. Phytopathology. 101(6S):26. Interpretive Summary:
Technical Abstract: We examined the plasmid content of a collection of 305 isolates of Erwinia amylovora from Washington and Oregon in the Pacific Northwest of the United States with PCR assays and RFLP. Nearly all isolates of E. amylovora carried plasmid pEA29, which is not found in other species of bacteria, but 4% of the isolates from this region lacked pEA29. The plasmid pEU30, previously reported in pathogen strains from western states in the United States, was detected in 28% of isolates. The RFLP patterns of plasmid preparations from a third of isolates from an epidemic in Washington in 1988 had altered RFLP patterns, possibly due to the presence of plasmid(s) in addition to pEA29 or pEU30. Considering all samples, the majority of isolates in this region were typical of E. amylovora and harbored only pEA29. Nonetheless, many of the pathogen isolates had altered plasmid content, indicating that plasmid acquisition and propagation in populations of E. amylovora in orchards in the Pacific Northwest is more common than previously assumed.