Molecular mapping of the RF9 gene from RCMG 1 for CMS ANN3 derived from wild sunflower (Helianthus annuus L.)

Authors: LIU, ZHAO - North Dakota State University; ZHANG, LIU - Jilin Baicheng Academy Of Agricultural Sciences; Seiler, Gerald; JAN, CHAO-CHIEN - Retired ARS Employee

Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/11/2023
Publication Date: 3/27/2023
Citation: Liu, Z., Zhang, L., Seiler, G.J., Jan, C. 2023. Molecular mapping of the RF9 gene from RCMG 1 for CMS ANN3 derived from wild sunflower (Helianthus annuus L.). Molecular Breeding. 219.Article 46. https://doi.org/10.1007/s10681-023-03176-3.
DOI: https://doi.org/10.1007/s10681-023-03176-3

Interpretive Summary: Globally, sunflower is the fifth largest oilseed crop and the second largest hybrid crop. It is produced on 50 million acres in 72 different counties. Modern sunflower hybrids are based on a single female cytoplasm resulting in a very narrow genetic base making it extremely vulnerable to attack by various biotic and abiotic factors. Genetic diversity can be increased by introducing new female and male parents. A new female cytoplasm based on an annual sunflower crop wild relative was discovered with the accompanying male line producing fertile hybrids. Closely linked molecular markers have been identified for the male gene allowing for its use in marker assisted selection in sunflower breeding programs. Diversification of the sunflower genetics will better help the crop adapt to the ever-challenging environment where it is grown.

Technical Abstract: Cytoplasmic male-sterile line CMS ANN3 was discovered from a wild Helianthus annuus L. accession PI 413180. A single dominant fertility restoration (Rf) gene for CMS ANN3 was identified in PI 413180, P 21, RHA 801, RCMG 1, and RHA 280, designated as Rf9. This study reports the mapping of the Rf9 locus using an F2 population of 160 individuals. Bulked segregant analysis with SSR primers identified two polymorphic SSR markers in linkage group (LG) 3 of the sunflower genetic map. A linkage map of Rf9 was constructed with 16 markers including 11 SSR/STS and five SNP markers, covering a genetic distance of 87.3 cM. The Rf9 gene is located between a co-dominant marker ORS1114 and a dominant marker NSA002021, with a distance of 4.1 and 1.0 cM, respectively. The physical distance between the two closest flanking markers corresponds to 1.44 and 2.52 Mb on the HA 412-HO and XRQ assemblies, respectively. The closely linked marker for Rf9 will facilitate marker-assisted selection (MAS) in breeding programs, which provides a basis for further characterization of this gene, and for studying the mechanism between cytoplasmic male sterility and Rf genes. The mapping of the Rf gene will also be useful for studying Rf gene suppression and nuclear-cytoplasm interactions.