Single nucleotide polymorphisms reveal multiple introductions into France of Plasmopara halstedii, the plant pathogen causing sunflower downy mildew
type: Dataset
description: Plasmopara halstedii, the causal agent of sunflower downy mildew, displays a gene-for-gene interaction with its host plant, Helianthus annuus and other species of the genus. Monitoring of the evolution of virulent races in France over a 19-year period led to the identification of 14 different races (or pathotypes). Twelve expressed sequence tag (EST)-derived markers displaying SNPs and insertion-deletion variations have recently been identified in P. halstedii. We used these markers to study the genetic structure and the evolution of sunflower downy mildew races. Bayesian assignment analysis identified three genetically differentiated groups of isolates organized around the first three races described in France. Strong genetic substructuring according to geographic origin of races was observed, confirming that these three groups corresponded to three separate introductions into France of isolates with different genetic and phenotypic backgrounds. Our results suggest that multiple introductions of P. halstedii isolates may have provided the raw material for more complex processes in the evolution of races, such as recombination between races or clonal evolution through mitotic instability.
issued: 2026-05-05T21:39:09.771693
language: en
modified: 2026-05-05T21:39:09.771697
contact point: Organization
  fn: CCSD
keyword: helianthus-annuus
keyword: infoeu-reposemanticsarticle
keyword: invasive-parasite
keyword: journal-articles
keyword: oomycetes
keyword: pathotype
keyword: plasmopara-halstedii
keyword: race
keyword: sdvbidevolife-sciences-q-biobiodiversitypopulations-and-evolution-q-biope
keyword: snp
keyword: virulence-profile
landing page: 1567-1348

Single nucleotide polymorphisms reveal multiple introductions into France of Plasmopara halstedii, the plant pathogen causing sunflower downy mildew
type: Distribution
format: HTML
issued: 2026-05-05T21:39:09.793570
modified: 2026-05-05T21:39:09.754324
access URL: https://hal.science/hal-00964382

test_moissonnage_selune
type: Agent