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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Mycology and Nematology Genetic Diversity and Biology Laboratory » Research » Publications at this Location » Publication #412808

Research Project: Fungal Systematics and Diagnostic Resource Development for Safeguarding Plant Health

Location: Mycology and Nematology Genetic Diversity and Biology Laboratory

Title: Phylogeography, origin, and population structure of the self-fertile emerging plant pathogen Phytophthora pseudosyringae

item MULLETT, MARTIN - Mendel University
item HARRIS, ANNA - Forest Research
item SCANU, BRUNO - University Of Sassari
item VAN POUCKE, KRIS - Flanders Research Institute For Agriculture
item LEBOLDUS, JARED - Oregon State University
item STAMM, ELIZABETH - Oregon State University
item Bourret, Tyler
item CHRISTOVA, PETYA - Agrobioinstitute
item OLIVA, JONAS - Universitat De Lleida
item REDONDO, MIGUEL - Mid Sweden University
item TALGO, VENCHE - Norwegian Institute Of Bioeconomy Research(NIBIO)
item CORCOBADO, TAMARA - Mendel University
item MILENKOVIC, IVAN - Mendel University
item HORTA JUNG, MARÍLIA - Mendel University
item WEBBER, JOAN - Forest Research
item HEUNGENS, KURT - Flanders Research Institute For Agriculture
item JUNG, THOMAS - Mendel University

Submitted to: Molecular Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/19/2024
Publication Date: 4/8/2024
Citation: Mullett, M.S., Harris, A.R., Scanu, B., Van Poucke, K., Leboldus, J., Stamm, E., Bourret, T.B., Christova, P.K., Oliva, J., Redondo, M.A., Talgo, V., Corcobado, T., Milenkovic, I., Horta Jung, M., Webber, J., Heungens, K., Jung, T. 2024. Phylogeography, origin, and population structure of the self-fertile emerging plant pathogen Phytophthora pseudosyringae. Molecular Plant Pathology. 25(4):e13450.

Interpretive Summary: Phytophthora is a genus of plant pathogens that pose grave threats to plants growing in agriculture, horticulture and natural ecosystems. Phytophthora pseudosyringae has been implicated in many disease outbreaks in Europe, North America and South America, but no one knows where the species originated. DNA analysis was used with a worldwide population of the species to answer this question. Results suggest that the species is ultimately native to Europe but was historically moved to North America. Since then, there has been movement of the pathogen in both directions. This information will be used by plant pathologists, regulatory officials and others involved in managing disease caused by P. pseudosyringae and preventing future introductions of this important plant pathogen.

Technical Abstract: Phytophthora pseudosyringae is a self-fertile pathogen of woody plants, particularly associated with tree species from the genera Fagus, Notholithocarpus, Nothofagus and Quercus, which is found across Europe and in parts of North America and Chile. It can behave as a soil pathogen infecting roots and the stem collar region, as well as an aerial pathogen infecting leaves, twigs and stem barks, causing particular damage in the United Kingdom and western North America. The population structure, migration and potential outcrossing of a worldwide collection of isolates were investigated using genotyping-by-sequencing. Coalescent-based migration analysis revealed that the North American population originated from Europe. Historical gene flow has occurred between the continents in both directions to some extent, yet contemporary migration is overwhelmingly from Europe to North America. Two broad population clusters dominate the global population of the pathogen, with a subgroup derived from one of the main clusters found only in western North America. Index of association and network analyses indicate an influential level of outcrossing has occurred in this preferentially inbreeding, homothallic oomycete. Outcrossing between the two main population clusters has created distinct subgroups of admixed individuals which are, however, less common than the main population clusters. Differences in life history traits between the two main population clusters should be further investigated together with virulence and host range tests to evaluate the risk each population poses to natural environments worldwide.