Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 14, 2006
Publication Date: July 1, 2006
Citation: Jan, C.C. 2006. Registration of two cytoplasmic male-sterile and eight fertility restoration sunflower genetic stocks. Crop Science. 46:1835-1836. Interpretive Summary: Two cytoplasmic male-sterile sunflower lines, cms ANN2-HA 89 and cms ANN3-HA 89, and eight corresponding fertility restoration lines, Rf ANN2-PI 413178, Rf ANN2-P21, Rf ANN2 -RMAX1, Rf ANN3-PI 413180, Rf ANN3-P21, Rf ANN3-RHA 801, Rf ANN3-RPET2, and Rf ANN3-RHA 280 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 due to the current use of a single male-sterile cytoplasm derived from wild H. petiolaris Nutt. PET1 (French) and a few fertility restoration genes. The new cms and corresponding fertility restoration lines will provide cytoplasmic diversity for hybrid sunflower production.
Technical Abstract: Male-sterile plants were identified in the wild H. annuus L. accessions PI 413178 and PI 413180, and maintained by backcrossing with the inbred line HA 89. Male-fertile progenies from crosses between cms plants of the two PIs and 12 USDA inbred lines indicated the presence of fertility restoration genes in P21, RMAX1, and PI 413178 for cms ANN2, and P21, RHA 280, RHA 801, RPET2, and PI 413180 for cms ANN3. Heterozygous male-fertile plants of backcross progenies crossed to cms plants resulted in a segregation ratio of one male-fertile to one male-sterile, indicating a single dominant gene controlling fertility restoration. In field tests, male-sterile PI 413178/4*HA 89 and PI 413180/4*HA 89 plants produced no seed after self-pollination, and 95% and 98% seed set, respectively, under open-pollination indicating complete male-sterility and female fertility. Cms ANN2-HA 89 and cms ANN3-HA 89 are BC6 bulk with the pedigree of cms PI 413178/7*HA 89 and cms PI 413180/7*HA 89, respectively, and have the cytoplasmic male sterility characteristic of not producing visible anthers during flowering. Cms ANN2-HA 89 and cms ANN3-HA 89 are single-headed, with respective plant heights of 121 and 136 cm, flower in 74 and 77 d after planting, head diam. of 15.9 and 14.6 cm, and 1000-seed weight of 62 and 58 g, and seeds are black with grey stripes. In comparison, HA 89 has a plant height of 132 cm, flowers in 73 d, head diam. of 14.8 cm, black with grey stripes seed color, 1000-seed weight of 69 g, and seed set percentage of 80%. Rf ANN2-PI 413178 is an F4 bulk with the pedigree of cms PI 413178/HA 89//PI 413178, F4. Rf ANN2-P21 is an F6 bulk with the pedigree of cms PI 413178/HA 89//cms PI 413178/P21, F6. Rf ANN2-RMAX1 is an F6 bulk with the pedigree of cms PI 413178/4*HA 89/3/cms PI 413178/RCMG1//RMAX1, F6. The respective plant height, days to flowering, head diameter, 1000 seed weight, and seed set percentage for Rf ANN2-PI 413178, Rf ANN2-P21, and Rf ANN2-RMAX1 are 170, 160 and 136 cm, 82, 89, and 85 days, 3.5, 9.9, and 5.1 cm, 8, 30, and 19 grams, and 44, 47, and 59%. Rf ANN2-PI 413178, Rf ANN2-P21, and Rf ANN2-RMAX1 are, single-headed, branched, branched, respectively, with seed color segregating for gray-mottle and black, segregating for black and gray with black stripes, and brown, respectively.