Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: SUSTAINABLE VINEYARD PRODUCTION SYSTEMS Title: Genetic structure of the fungal grapevine pathogen Eutypa lata from four continents

Authors
item Travadon, Renaud -
item Baumgartner, Kendra
item Rolshausen, Philippe -
item Gubler, Walter Douglas -
item Sosnowski, Mark -
item Lecomte, Pascal -
item Halleen, Francois -
item Peros, Jean-Pierre -

Submitted to: Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 2, 2011
Publication Date: N/A

Interpretive Summary: The fungus Eutypa lata causes Eutypa dieback of grapevine (Vitis vinifera) worldwide. To identify where this pathogen originating from, in geographic terms, we investigated the population genetic structure of 20 geographic populations from four continents, based on analyses of 294 isolates genotyped with nine microsatellite markers. The greatest levels of genetic diversity were found in Europe, where isolates of the pathogen were divided into two groups of genetically-divergent clusters: one cluster included isolates mainly from inland areas of Europe, and the other cluster, genetically more diverse, included isolates mainly from coastal areas surrounding the Mediterranean Sea. Populations in California, Australia and South Africa, all of which had significantly lower genetic diversity than in Europe, were also characterized by demographic disequilibrium, and thus may represent introduced populations of the pathogen. Because the clusters in California, Australia, and South Africa were not so genetically-distinct from that the inland European cluster, it is possible that, first Europe is the origin of these three other populations and that there has been a relatively short period of time since introduction. The patterns of genetic diversity among the populations are consistent with the historic, worldwide movement of the pathogen’s host, V. vinifera, and the history of its cultivation.

Technical Abstract: Deciphering the geographic origins of pathogens and elucidating the population biology of these microscopic organisms are necessary steps to establish effective disease-control strategies. The generalist ascomycete fungus Eutypa lata causes Eutypa dieback of grapevine (Vitis vinifera) worldwide. To identify centers of diversity and new introduction areas for E. lata, and to reveal migration patterns among continents, we investigated the population genetic structure of 20 geographic populations from four continents, based on analyses of 294 isolates genotyped with nine microsatellite markers. The greatest levels of genetic diversity were found in Europe, where two genetically-divergent clusters were identified. One cluster included isolates mainly from inland areas. The other cluster, genetically more diverse, included isolates mainly from coastal areas surrounding the Mediterranean Sea. Populations in California, Australia and South Africa, all of which had significantly lower genetic diversity than in Europe, were also characterized by demographic disequilibrium, and thus may represent founding populations of the pathogen. Low levels of genetic differentiation between the inland European cluster and the three putative founding populations suggest that they have a European origin, with a relatively short period of time since introduction. The patterns of genetic diversity among the populations are consistent with the historic, worldwide movement of the pathogen’s host, V. vinifera, and the history of its cultivation.

Last Modified: 10/30/2014
Footer Content Back to Top of Page