PCR method to detect both Xanthomonas axonopodis pv. phaseoli and Pseudomonas syringae pv. phaseolicola in bean seeds
A rapid and sensitive PCR method to detect at the same time Xanthomonas axonopodis pv. phaseoli (X. campestris pv. phaseoli - EPPO A2 quarantine pest) and Pseudomonas syringae pv. phaseolicola in bean seeds was developed in Canada. This method includes a rapid DNA extraction procedure, with a brief wetting of seeds with a solution of sodium hydroxide. A combination of specific primers is used to detect the two bacteria specifically, other plant pathogenic bacteria tested did not give positive results. This is a sensitive method which can detect as few as 1 infected seed in 10,000 seeds. However, for coloured bean seeds, polyvinylpyrolidone (PVP) has to be added to the extraction buffer to obtain amplification. The authors concluded that their method has a great potential for the detection of these two bacteria in commercial seed lots.
Sources
Audy, P.; Braat, C.E.; Saindon, G.; Huang, H.C.; Laroche, A. (1996) A rapid and sensitive PCR-based assay for concurrent detection of bacteria causing common and halo blights in bean seed.
Phytopathology, 86(4), 361-366.