Lashermes Philippe, Combes Marie-Christine, Ribas Alessandra, Cenci Alberto, Mahé L., Etienne H. (2010). Genetic and physical mapping of the S(H)3 region that confers resistance to leaf rust in coffee tree (Coffea arabica L.). Tree Genetics and Genomes, 6 (6), p. 973-980. ISSN 1614-2942.
Titre du document
Genetic and physical mapping of the S(H)3 region that confers resistance to leaf rust in coffee tree (Coffea arabica L.)
Tree Genetics and Genomes, 2010,
6 (6), p. 973-980 ISSN 1614-2942
Resistance to coffee leaf rust is conferred by S(H)3, a major dominant gene that has been introgressed from a wild coffee species Coffea liberica (genome L) into the allotetraploid cultivated species, Coffea arabica (genome (CEa)-E-a). As the first step toward the map-based cloning of the S(H)3 gene, using a bacterial artificial chromosome (BAC) library, we describe the construction of a physical map in C. arabica spanning the resistance locus. This physical map consists in two homeologous BAC-contigs of 1,170 and 1,208 kb corresponding to the subgenomes C-a and E-a, respectively. Genetic analysis was performed using a single nucleotide polymorphism detection assay based on Sanger sequencing of amplicons. The C. liberica-derived chromosome segment that carries the S(H)3 resistance gene appeared to be introgressed on the sub-genome C-a. The position of the S(H)3 locus was delimited within an interval of 550 kb on the physical map. In addition, our results indicated a sixfold reduction in recombination frequency in the introgressed S(H)3 region compared to the orthologous region in Coffea canephora.
