Registration of Seven Cytoplasmic Male‐Sterile and Four Fertility Restoration Sunflower Germplasms

Seven cytoplasmic male-sterile sunflower (Helianthus annuus L.) lines, cmsANN14 (Reg. no.GP-306, PI 642073), cmsMUT7 (Reg. no. GP-307, PI 642074), cmsMUT8 (Reg. no. GP-308, PI 642075), cmsMUT9 (Reg. no.GP-309, PI 642076), cmsMUT10 (Reg. no. GP-310, PI 642077), cms MUT11 (Reg. no. GP-311, PI 642078), and cmsMUT12 (Reg. no. GP-312, PI 642079), and four corresponding fertility restoration lines, Rf Armavir (Reg. no. GP313, PI 642080), Rf PI 432513 (Reg. no. GP-314, PI 642081), Rf VNIIMK (Reg. no. GP-315, PI 642082), and Rf P21 (Reg. no. GP-316, PI 642083), were cooperatively developed and released by the USDA-ARS and the North Dakota Agricultural Experiment Station, Fargo, ND, in 2005. New sources of cytoplasmic male-sterility and fertility restoration genes will help reduce the genetic vulnerability of commercial sunflower hybrids due to the current use of a single male-sterile cytoplasm, PET1 (French) derived from wild H. petiolaris Nutt., and a few fertility restoration genes. The new cms and fertility restoration lines will provide cytoplasmic diversity for hybrid sunflower production. Cms ANN14 originated from one male-sterile plant identified in a Native American landrace PI 432513, and is a BC5 bulk with the pedigree of cms PI 432513/6*HA 89. Restoration genes for cms PI 432513 were found in plants from ‘Armavir’ (PI 372254), ‘VNIIMK’ (PI 265503), and male-fertile plants of PI 432513. They were also found in P21 (P21 VR1), a nuclear male-sterile line released by the USDA-ARS and the Texas Agricultural Experiment Station in 1970. F2 segregation ratios of crosses between cms PI 432513 and these restoration sources indicate a single dominant gene control of fertility restoration. Rf Armavir is an F6 bulk with the pedigree of cms PI 432513/PI 432513//Armavir, F6. Rf PI 432513 has the pedigree of cms PI 432513/PI 432513, F6. Rf VNIIMK has the pedigree of cms PI 432513/PI 432513//VNIIMK, F6 and Rf P21 has the pedigree of cms PI 432513/PI 432513//P21, F6. Rf Armavir, Rf PI 432513, Rf VNIIMK, and Rf P21 have a pollen stainability of 65, 78, 96, and 88%, respectively, and selfpollinated seed set of 15, 25, 44, and 40%, indicating varying degrees of self-incompatibility. Cms MUT7 through cms MUT12 originated from mytomycin C and streptomycin induced HA 89, with respective designations of cms 45–1, cms 139–1, cms 491–1, cms 515–1, cms 555–1, and cms 3149. M1 selection of cms MUT7 was from an M1 head that had yellow anthers, but later segregated for male-sterile progenies (Jan and Rutger, 1988). M1 heads of cms MUT11 were completely male sterile, while M1 heads of cms MUT8, cms MUT9, cms MUT10, and cms MUT12 had malesterile sectors of the head of 10, 19, 17, and 4%, respectively. Cms MUT7 through cms MUT12 were maintained by backcrossing with HA 89, and the bulked BC3 seeds, with the general pedigree of cms M2 plants/4*HA 89, are the male-sterile germplasm lines included in these releases. Cms ANN14 and cms MUT 7 through cms MUT12 are also completely restored by restorer lines RHA 266, RHA 274 (PI 599759), RHA 280 (PI 552943), and RHA 296 (PI 552931), and their F2 segregation ratios indicate a single dominant gene control, implying a common cytoplasmic male sterility similarity in all lines and that the Rf1 gene was a factor in their restoration (Jan and Vick, 1997, 1998). RHA 266 was released by USDAARS and Texas Agricultural Experiment Station, College Station, Texas, in 1971. Since the only cms source used in all current cultivated sunflower hybrids, cms PET1, is froma closely related species, H. petiolaris, the new cytoplasmic sources from H. annuus are expected to have fewer adverse interactions with the nuclear genes from H. annuus when used for hybrid production. In addition, the complete restoration of the new cms sources by genes already in commercial restoration lines will enable breeders to focus on other traits in cms line development, increasing the efficiency of hybrid development programs. Cms MUT7, cms MUT8, cms MUT9, cms MUT10, cms MUT11, cms MUT12, cms ANN14, and cms HA 89 flower in 73, 73, 74, 72, 73, 75, 73, 73 d after planting, have a plant height of 128, 132, 128, 139, 134, 133, 135, 132 cm, head diameter of 14.6, 14.5, 14.1, 16.4, 14.0, 14.9, 14.5, 14.8 cm, and a 1000-seed weight of 58, 56, 56, 62, 65, 67, 65, 51 g, respectively. All cms germplasms are single-headed, having the characteristic cytoplasmic male-sterility of not producing visible anthers during flowering, and having over 95% seed set from open-pollination. Cms ANN14 segregated for seed coat color of black and black with gray stripes, and cms MUT7 through cms MUT12 are black with gray stripes. Rf Armavir, Rf PI 432513, Rf VNIIMK, and Rf P21 are segregating for branching and non-branching, single headed, segregating for branching and non-branching, and segregating for branching and nonbranching, respectively. The seed coat colors are segregating for black and brown, black, segregating for black and gray, and black, respectively. Limited quantities of seed of each germplasm line are available on request from the corresponding author for 5 yr. Recipients of seed are asked to make appropriate recognition of the source of the genetic stocks if they are used in the development of a new cultivar, germplasm, parental line, or hybrid.