Positional cloning of a candidate gene for resistance to the sunflower downy mildew, Plasmopara halstedii race 300.
The resistance of sunflower to Plasmopara halstedii is conferred by major resistance genes denoted Pl. Previous genetic studies indicated that the majority of these genes are clustered on linkage groups 8 and 13. The Pl6 locus is one of the main clusters to have been identified, and confers resistance to several P. halstedii races. In this study, a map-based cloning strategy was implemented using a large segregating F2 population to establish a fine physical map of this cluster. A marker derived from a bacterial artificial chromosome (BAC) clone was found to be very tightly linked to the gene conferring resistance to race 300, and the corresponding BAC clone was sequenced and annotated. It contains several putative genes including three toll-interleukin receptor-nucleotide binding site-leucine rich repeats (TIR-NBS-LRR) genes. However, only one TIR-NBS-LRR appeared to be expressed, and thus constitutes a candidate gene for resistance to P. halstedii race 300.
Clermont Université, Université Blaise Pascal, UMR INRA-UBP 1095 GDEC, BP 10448, 63000 Clermont-Ferrand, France.
Jérôme
J
Franchel
Mohamed Fouad
MF
Bouzidi
Gisèle
G
Bronner
Felicity
F
Vear
Paul
P
Nicolas
Said
S
Mouzeyar
D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics; D003001:Cloning, Molecular; D003433:Crosses, Genetic; D018744:DNA, Plant / Q000235:genetics; D060467:Disease Resistance / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics*; D006368:Helianthus / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D007113:Immunity, Innate; D008969:Molecular Sequence Data; D009868:Oomycetes / Q000472:pathogenicity / Q000502:physiology*; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D040641:Quantitative Trait Loci; D018749:RNA, Plant / Q000235:genetics; D017386:Sequence Homology, Amino Acid
D018744:DNA, Plant; D018749:RNA, Plant