International Journal of Plant Breeding and Genetics ISSN 2756-3847 Vol. 10 (6), pp. 001-009, June, 2023. © International Scholars Journals
Full Length Research Paper
Marker Development and Fine-Mapping of Downy Mildew (Plasmopara halstedii) (DM) Resistance PlArg in Sunflower (Helianthus annuus) using nested-association-mapping (NAM) Populations
Zining Wang ( ), Wayne (Hui) Shen, Géza Mészáros, Kathy Smith, David Pang, Steve Calhoun
Zining Wang( ),Wayne Shen, David Pang, S & W Seed Company, TTU Innovation Hub at Research Park, 3911 4th St, M.S. 3005, Lubbock TX 79415, USA.
Géza Mészáros, S & W Seed Company, 11 Új Élet utca, Szeged, H-6710, Hungary.
Kathy Smith, S&W Seed Company, Nampa Laboratory, 4819 Lewis Lane, NAMPA, Idaho 83686, USA.
Steve Calhoun, S&W Seed Company, 6615 Winfield St, Lubbock TX 79407, USA.
Accepted 15 March, 2023
Abstract
Downy Mildew (Plasmopara halstedii) in Sunflower (Helianthus annuus) is a serious disease worldwide. The resistance gene PlArg from Helianthus argophyllus has been confirmed to be the most effective gene to date against DM races. Previously reported molecular markers for PlArg are of limited value for marker assisted selection (MAS) across diverse germplasm. In this study, we used the published markers, NAM populations, two consensus genetic maps and three versions of genome assemblies to test the flanking markers D2384 and D2395. We also developed a new SSR marker D2564, co-segregating with PlArg but in a genomic region not previously reported. After further screening new SSR markers in this region using the small population, D2317 was the closest marker to PlArg. Further, we tested D2317 with a larger NAM population of 256 families and a F2:3 population of 126 families. It co-segregated with PlArg. D2317 has four bands in the genome and lands in two resistance-like genes, HanXRQChr01g0018861 and HanXRQChr01g0018891 separately. In this study, we used comparative genomic tools and NAM populations to develop the causal marker D2317 and find candidate genes for PlArg. This marker will have broad applications for MAS and will aid the cloning of PlArg resistance genes.
Keywords: Sunflower, marker development, fine mapping, Plarg, DM resistance, recombination depression, candidate genes, MAS.
Full Length Research Paper
Marker Development and Fine-Mapping of Downy Mildew (Plasmopara halstedii) (DM) Resistance PlArg in Sunflower (Helianthus annuus) using nested-association-mapping (NAM) Populations
Zining Wang (
), Wayne (Hui) Shen, Géza Mészáros, Kathy Smith, David Pang, Steve Calhoun
Zining Wang(
),Wayne Shen, David Pang, S & W Seed Company, TTU Innovation Hub at Research Park, 3911 4th St, M.S. 3005, Lubbock TX 79415, USA.
Géza Mészáros, S & W Seed Company, 11 Új Élet utca, Szeged, H-6710, Hungary.
Kathy Smith, S&W Seed Company, Nampa Laboratory, 4819 Lewis Lane, NAMPA, Idaho 83686, USA.
Steve Calhoun, S&W Seed Company, 6615 Winfield St, Lubbock TX 79407, USA.
Abstract
Accepted 15 March, 2023 |
Downy Mildew (Plasmopara halstedii) in Sunflower (Helianthus annuus) is a serious disease worldwide. The resistance gene PlArg from Helianthus argophyllus has been confirmed to be the most effective gene to date against DM races. Previously reported molecular markers for PlArg are of limited value for marker assisted selection (MAS) across diverse germplasm. In this study, we used the published markers, NAM populations, two consensus genetic maps and three versions of genome assemblies to test the flanking markers D2384 and D2395. We also developed a new SSR marker D2564, co-segregating with PlArg but in a genomic region not previously reported. After further screening new SSR markers in this region using the small population, D2317 was the closest marker to PlArg. Further, we tested D2317 with a larger NAM population of 256 families and a F2:3 population of 126 families. It co-segregated with PlArg. D2317 has four bands in the genome and lands in two resistance-like genes, HanXRQChr01g0018861 and HanXRQChr01g0018891 separately. In this study, we used comparative genomic tools and NAM populations to develop the causal marker D2317 and find candidate genes for PlArg. This marker will have broad applications for MAS and will aid the cloning of PlArg resistance genes.
Keywords: Sunflower, marker development, fine mapping, Plarg, DM resistance, recombination depression, candidate genes, MAS.