31 Powney, R Plummer, K Luck, J Beer, S Rodoni, B. 2007 Evaluation of PCR-based Protocols for the Detection of Erwinia amylovora XI International Workshop on Fire Blight Acta Horticulturae diagnostics, identification <p>Incursion management relies on fast and accurate pathogen identification in order to mobilize controls against devastating disease outbreaks. In the last decade, polymerase chain reaction (PCR) has been used to identify and detect many plant pathogens, including <em>Erwinia amylovora</em>, the causal agent of fire blight. The most widely accepted PCR-based diagnostics for the detection of <em>E. amylovora</em> target the pEA29 plasmid, which until recently was thought to be associated with all known virulent strains of <em>E. amylovora</em>. The discovery in Spain of a virulent strain of <em>E. amylovora </em>that does not bear amplification products with primers based on pEA29 has put the specificity of this test into question. Recent surveys of selected rosaceous plants in South Eastern Australia resulted in the isolation of a range of saprophytic bacteria. Whilst the microbiological characteristics of these bacteria were not consistent with those of <em>E. amylovora </em>and they were not pathogenic when inoculated into immature pear fruit, amplification products were obtained using both pEA29 and chromosomal-based primer pairs. We propose to subject a collection of known strains of <em>E. amylovora </em>and saprophytic bacteria isolated from rosaceous hosts of <em>E. amylovora</em> in Australia and elsewhere, to all published PCR-based diagnostic protocols for evaluating their accuracy in detection and identification of <em>E. amylovora</em>.</p>