Emerging races arising from recombination facilitated by multiple introductions of the sunflower downy mildew Plasmopara halstedii in France
نویسندگان
چکیده
Background to the research and aims. French pathologists have been intensively monitoring the prevalence of sunflower downy mildew in France over a 20 years period. Despite efforts to produce resistant varieties of sunflower, this monitoring has revealed that there has been a recent and rapid emergence of new and endemic (found only in France) races, that has led to an increase from one original founding race in 1966 to 14 races found today (Moinard et al. 2006).
منابع مشابه
RXLR and CRN Effectors from the Sunflower Downy Mildew Pathogen Plasmopara halstedii Induce Hypersensitive-Like Responses in Resistant Sunflower Lines
Plasmopara halstedii is an obligate biotrophic oomycete causing downy mildew disease on sunflower, Helianthus annuus, an economically important oil crop. Severe symptoms of the disease (e.g., plant dwarfism, leaf bleaching, sporulation and production of infertile flower) strongly impair seed yield. Pl resistance genes conferring resistance to specific P. halstedii pathotypes were located on sun...
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