A duplex PCR method for the simultaneous identification of Phytophthora ramorum and Phytophthora kernoviae

Phytophthora ramorum and Phytophthora kernoviae are two fungus‐like organisms affecting a wide range of hardy ornamental plants and trees. Emergency measures are implemented in the European Union for P. ramorum and aim to eradicate, or at least prevent the further spread of this harmful pathogen. Phytophthora kernoviae has so far been found only in New Zealand, the UK and Ireland, and is regulated on a UK level using the same measures as for P. ramorum. Both Phytophthora species have a similar host range and can be diagnosed using similar methods. Therefore a duplex PCR detection, based on the internal transcribed spacer (ITS) regions of the ribosomal DNA, was developed to enable simultaneous testing to reduce diagnostic times. The method was tested for its specificity and sensitivity, and on plant samples, and was shown to be reliable for identification of the two organisms.