Real-time PCR to detect Phytophthora ramorum and P. pseudosyringae
A real-time PCR test has been developed in the USA to detect Phytophthora ramorum (EPPO Alert List) and Phytophthora pseudosyringae. P. pseudosyringae is a newly described species reported in Europe and the USA which can cause similar symptoms (see EPPO RS 2005/162). This real-time PCR assay is based upon mitochondrial DNA sequences and uses specific primers for both Phytophthora species in a multiplex reaction. This assay was tested successfully on infected field samples. It was found to be highly sensitive (more sensitive than many other PCR procedures) and specific. It is planned to expend this technique to the simultaneous detection of P. nemorosa, which is another pathogen (so far, only reported in the USA, in California and Oregon) occurring with P. ramorum.
Sources
Tooley PW, Martin FN, Carras MM, Frederick RD (2006) Real-time fluorescent polymerase chain reaction detection of Phytophthora ramorum and Phytophthora pseudosyringae using mitochondrial gene regions. Phytopathology 96(4), 336-345.