title: Major-effect QTLs for stem and foliage resistance to late blight in the wild potato relatives Solanum sparsipilum and S. spegazzinii are mapped to chromosome X.
abstract: To find out new resistance sources to late blight in the wild germplasm for potato breeding, we examined the polygenic resistance of Solanum sparsipilum and S. spegazzinii by a quantitative trait locus (QTL) analysis. We performed stem and foliage tests under controlled conditions in two diploid mapping progenies. Four traits were selected for QTL detection. A total of 30 QTLs were mapped, with a large-effect QTL region on chromosome X detected in both potato relatives. The mapping of literature-derived markers highlighted colinearities with published late blight QTLs or R-genes. Results showed (a) the resistance potential of S. sparsipilum and S. spegazzinii for late blight control, and (b) the efficacy of the stem test as a complement to the foliage test to break down the complex late blight resistance into elementary components. The relationships of late blight resistance QTLs with R-genes and maturity QTLs are discussed.
authors.affiliation: INRA, UR 1052 GAFL Génétique et Amélioration des Fruits et Légumes, BP 94, 84140, Montfavet, France.
authors.forename: Sarah
authors.initials: S
authors.lastname: Danan
authors.forename: Jean-Eric
authors.initials: JE
authors.lastname: Chauvin
authors.forename: Bernard
authors.initials: B
authors.lastname: Caromel
authors.forename: Jean-Denis
authors.initials: JD
authors.lastname: Moal
authors.forename: Roland
authors.initials: R
authors.lastname: Pellé
authors.forename: Véronique
authors.initials: V
authors.lastname: Lefebvre
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics*; D004843:Epistasis, Genetic; D005819:Genetic Markers; D007113:Immunity, Innate / Q000235:genetics; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology*; D018515:Plant Leaves / Q000235:genetics*; D018547:Plant Stems / Q000235:genetics*; D025341:Principal Component Analysis; D040641:Quantitative Trait Loci / Q000235:genetics*; D011198:Solanum tuberosum / Q000235:genetics*
chemical_list: D005819:Genetic Markers