Submitted to: Letters in Applied Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/25/2004
Publication Date: 5/1/2004
Citation: Letters in Applied Microbiology 38:433-439
Interpretive Summary: A technique based on the conformation of single DNA strands was used to identify the plant pathogen Phytophthora ramorum, which causes sudden oak death disease. The technique, known as SSCP, is a relatively new method not often applied to identification of plant disease fungi. The method differentiated P. ramorum from 18 related species of Phytophthora, showing that it is a potentially useful new tool for identification of this important pathogen. The research provides a simple, rapid and reliable tool for confirming positive detections in ongoing surveys for P. ramorum in nurseries and forest areas in the eastern U.S.
Technical Abstract: The primary objectives of this study were to determine if a single-strand-conformation polymorphism (SSCP) analysis can be used for rapid identification of Phytophthora ramorum, an important quarantine plant pathogen worldwide, and to further assess the potential of the SSCP technique as a taxonomic tool for the genus Phytophthora. SSCP of ribosomal DNA internal transcribed spacer 1 was characterized for 12 isolates of P. ramorum, using a recently reported protocol. The SSCP patterns of this species then were compared with those of 18 closely related Phytophthora species. Phytophthora ramorum had a unique pattern and was easily distinguished from genetically, morphologically, and ecologically close relatives. An immediate benefit of this study is provision of a highly effective and efficient identification tool for P. ramorum in the quarantine process. This study also provides additional evidence demonstrating that the SSCP is an ideal DNA marker for species differentiation within the genus Phytophthora.