Submitted to: Crop Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/13/2006
Publication Date: 7/1/2006
Citation: Jan, C.C., Miller, J.F., Seiler, G.J., Fick, G.N. 2006. Registration of one cytoplasmic male-sterile and two fertility restoration sunflower genetic stocks. Crop Science. 46:1835. Interpretive Summary: Cytoplasmic male-sterile line, cms RIGX-HA 89, and two corresponding fertility restoration lines, Rf RIGX-Luch and Rf RIGX-RCMG1 were developed and released in 2005. New sources of cytoplasmic male-sterility and fertility restoration genes will help reduce the genetic vulnerability of commercial sunflower hybrids because of the current use of a single male-sterile, PET1 (French), cytoplasm derived from H. petiolaris Nutt.and a few fertility restoration genes. These new cms and corresponding fertility restoration lines will provide cytoplasmic diversity for hybrid sunflower production.
Technical Abstract: Seed of the cms source RIGX, derived from H. pauciflorus (rigidus) Nutt. in cultivated background, was obtained through a scientific exchange with former Soviet Union in 1987, and was increased by crossing with the inbred line HA 89 (PI 599773) and bulked pollen of several wild H. annuus L. (WA) accessions. Crosses between male-sterile plants, with the pedigree of cms-RIGX/HA 89//WA/3/HA 89, and 21 prospective restoration lines indicated the presence of fertility restoration genes in 'Luch' and 'RCMG1'. Cms RIGX-HA89 is a BC7 bulk with the pedigree of cms RIGX/HA 89//WA/3/7*HA 89 and has the cytoplasmic male-sterility characteristic of producing no visible anthers during flowering. In field tests, cms RIGX-HA 89 plants produced no seeds after self-pollination, and 99% seed set from open-pollination, indicating complete male-sterility and female-fertility. Rf RIGX-Luch is an F6 bulk homozygous for the restoration genes, with the pedigree of cms RIGX/2*HA 89/3/cms RIGX/HA 89//WA/4/2*HA 89/7/ cms RIGX/2*HA 89/3/cms RIGX/HA 89//WA/4/2*HA 89/6/cms RIGX/2*HA 89/3/cms RIGX/HA 89//WA/4/HA 89/5/Luch. Rf RIGX-RCMG1 is an F7 bulk homozygous for the restoration genes, with the pedigree of cms RIGX/2*HA 89/3/cms RIGX/HA 89//WA/4/2*HA 89/7/ cms RIGX/2*HA 89/3/cms RIGX/HA 89//WA/4/2*HA 89/6/cms RIGX/2*HA 89/3/cms RIGX/HA 89//WA/4/HA 89/5/RCMG1. CmsRIGX-HA89 is non-branched, with a plant height of 96 cm, flowers 79 d after planting (DAF), and has a head diam. of 12.9 cm. Seeds are black with grey stripes, with a 1000-seed weight of 60 g. Rf RIGX-Luch and Rf RIGX-RCMG1 are also non-branched, with plant heights of 65 and 97 cm, flowers 66 and 68 DAP, and has seed set percentages of 59 and 81%, respectively. Seeds of Rf RIGX-Luch and Rf RIGX-RCMG1 are black with grey stripes, and have 1000 seed weights of 42 and 58 grams, respectively. In comparison, HA 89 has a plant height of 132 cm. 73 d to flowering, head diam. Of 14.8 cm, black with grey stripes seed color, 1000-seed weight of 69 g, and seed set percentage of 70%.