Molecular mapping of the genomic region conferring resistance to soybean stem canker in Hutcheson soybean.

CHIESA, M.A.; MORANDI, E.N.; CAMBURSANO, M.V.; PIOLI, R.N.

MOLECULAR BREEDING

SPRINGER

Lugar: Berlin; Año: 2017 vol. 37 p. 65 - 76

1380-3743

Abstract Genetic resistance to soybean stem canker,caused by the fungus Diaporthe phaseolorum var.meridionalis (Dpm), is controlled by five major, dominant,nonallelic genes Rdm1 to Rdm5. A genomic region containing the Rdm4 and Rdm5 genes was first described in Hutcheson soybean, where they were found to confer specific resistance to Argentinean physiological races of Dpm. Here, we report the genetic mapping of Rdm4 and Rdm5 loci using two pheno- and genotypicallycharacterized F2:3 populations derived from Hutcheson cultivar. The mapping populations were screened with amplified fragment length polymorphism (AFLP) markers using bulk segregant analysis, and withsimple sequence repeat (SSR) markers. Linkage analysis indicated that the Rdm4 and Rdm5 resistance loci were located in a genomic region collinear with themolecular linkage group (MLG) A2 (chromosome 8)of the soybean genetic map. The linkage group contains two SSR markers, Sat_162 and Satt233, flanking the Rdm4 and Rdm5 loci. These SSR will be useful toincrease the efficiency of selection in breeding programs aimed to incorporate Rdm4 and Rdm5 genes into soybean elite germplasm.