Quantitative Real-Time PCR Assay for the Detection of , a Causal Agent of Potato Soft Rot.

is a plant-pathogenic bacterium, recently attributed as a separate species, which infects potatoes, causing soft rot in tubers. The distribution of seems to be global, although the bacterium tends to be accommodated to moderate climates. Fast and accurate detection systems for this pathogen are needed to study its biology and to identify latent infection in potatoes and other plant hosts. The current paper reports on the development of a specific and sensitive detection protocol based on a real-time PCR with a TaqMan probe for , and its evaluation. In sensitivity assays, the detection threshold of this protocol was 10 cfu/mL on pure bacterial cultures and 10-10 cfu/mL on plant material. The specificity of the protocol was evaluated against and more than 100 strains of potato-associated species of and . No cross-reaction with the non-target bacterial species, or loss of sensitivity, was observed. This specific and sensitive diagnostic tool may reveal a wider distribution and host range for and will expand knowledge of the life cycle and environmental preferences of this pathogen.