|VALENTINI, G - University Of Brazil|
|GONÇALVES-VIDIGAL, M - University Of Brazil|
|CREGAN, P - Retired ARS Employee|
|Pastor Corrales, Marcial - Talo|
Submitted to: Bean Improvement Cooperative Annual Report
Publication Type: Trade Journal
Publication Acceptance Date: 7/1/2015
Publication Date: 8/1/2015
Citation: Valentini, G., Gonçalves-Vidigal, M.C., Cregan, P., Song, Q., Pastor Corrales, M.A. 2015. Using SNP genetic markers to elucidate the linkage of the Co-34/Phg-3 anthracnose and angular leaf spot resistance gene cluster with the Ur-14 resistance gene . Bean Improvement Cooperative Annual Report. 58:21-22.
Technical Abstract: The Ouro Negro common bean cultivar contains the Co-34/Phg-3 gene cluster that confers resistance to the anthracnose (ANT) and angular leaf spot (ALS) pathogens. These genes are tightly linked on chromosome 4. Ouro Negro also has the Ur-14 rust resistance gene, reportedly in the vicinity of Co- 34; however, the relationship between Co- 34 and Ur-14 has not been established. The objective of this study was to use single nucleotide polymorphism (SNP) DNA markers to determine if these two genes were linked. We inoculated 108 F2:3 families derived from the cross Rudá (susceptible) × Ouro Negro (Resistant) with races of the ANT and rust pathogens. All but one of the 108 F2:3 families that were resistant or susceptible to rust, had the same reaction to the anthracnose pathogen, showing that Ur-14 and Co-34 co segregate and revealing that they were tightly linked to each other. DNA from each plant of the F2:3 families was used to genotype them with 5,399 SNPs DNA markers. Polymorphic SNP markers that separated the resistant from the susceptible families were found. These SPN markers were used to find SSR (simple sequence repeats) DNA markers which are easy to visualize. SSR markers tightly linked with the Ur-14 and with Co-34 genes were also found. The mapping of these genes with the SSR markers corroborated that Ur-14 and Co-34 were tightly linked, showing that the newly discovered SSR markers could be used in marker-assisted selection to identify bean cultivars with the Co-34/Phg-3 and Ur-14 disease resistance genes.