Location: Sunflower and Plant Biology ResearchTitle: 2021 Progress for enhancing rust resistance in confection sunflower production through next-generation technologies
|MA, GUOJIA - North Dakota State University|
|LI, XUEHUI - North Dakota State University|
Submitted to: National Sunflower Research Forum Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 1/13/2022
Publication Date: N/A
Technical Abstract: In 2021, we selected the homozygous triple pyramids with two rust and one downy mildew genes, R12/R15/PlArg from the cross of HA-DM2/HA-R8 and R13a/R15/Pl17 from cross of HA-DM3/HA-R8, respectively, using DNA markers. The F2-derived F3 families were grown in the field for seed increase. We completed fine mapping of the rust resistance gene (R gene) R13a and located this gene to a region covering 0.4787 cM genetic distance, which corresponds to a physical interval of 750 kb in the XRQ reference genome. Three putative genes, HanXRQChr13g0425851, HanXRQChr13g0425891, and HanXRQChr13g0425931 with NB-ARC domains were found in this region. We have made significant progress in fine mapping of the rust R gene R12 in marker development and recombinant screen from a large population. R12 was previously mapped to a region of 3.5 Mb. A total of 48 new markers including four SSRs and 44 SNPs from the whole-genome resequencing were currently mapped to the R12 target region in a saturation map. SSR marker SUN129 developed in the current study and SNP marker SFW01570 flanking R12 were used to screen 3,008 F3 individuals selected from the F3 families heterozygous for R12. A total of 104 F3 individuals with recombination events close to the R12 gene were identified and advanced to the next generation. Phenotypic evaluation and genotyping of the selected recombinants are underway for fine mapping of R12.