New Phytologist (2016) 210, 1443-1452

Thibault Leroy, Valérie Caffier, Jean-Marc Celton, Nicolas Anger, Charles-Eric Durel, Christophe Lemaire and Bruno Le Cam (2016)
When virulence originates from nonagricultural hosts: evolutionary and epidemiological consequences of introgressions following secondary contacts in Venturia inaequalis
New Phytologist 210 (4), 1443-1452
Abstract: - In pathogens, introgressions through secondary contacts between divergent populations from agricultural and nonagricultural disease reservoirs are expected to have crucial evolutionary and epidemiological implications. Despite the importance of this question for disease management, experimental demonstrations of these implications remain scarce.
- Recently, we identified a virulent population of the apple scab pathogen Venturia inaequalis that migrated from nonagricultural hosts to European domestic apple orchards. Here, we investigated the occurrence of gene flow between agricultural and nonagricultural populations sampled in two orchards, and thereafter its consequences on the pathogenicity of hybrids.
- Population genetic structure and demographic inferences based on the genotypes of 104 strains revealed a high amount of gene flow between the two populations in one orchard. In this site, mating between populations was made possible by the presence of a common host. Our results revealed an invasion of the virulent trait in the agricultural population; a main direction of introgression in hybrids from the agricultural to nonagricultural genetic backgrounds; and a population of hybrids with transgressive traits.
- We demonstrate a secondary contact with gene flow between divergent populations of pathogens. Our findings highlight evolutionary and epidemiological changes in pathogens and have concrete implications for sustainable disease management.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Charles Eric Durel

Research topic(s) for pests/diseases/weeds:
population dynamics/ epidemiology

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Venturia inaequalis