Submitted to: Sunflower International Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/30/2004
Publication Date: 8/29/2004
Citation: Jan, C.C. 2004. A new CMS source from Helianthus giganteus and its fertility restoration genes from interspecific amphiploids. International Sunflower Conference Proceedings. 16th International Sunflower Conference, August 29-September 2, 2004, Fargo, ND. p. 709-712. Interpretive Summary: New sources of cytoplasmic male sterility (CMS) and fertility restoration genes would reduce the genetic vulnerability of commercial sunflower (Helianthus annuus L.) hybrids resulting from the current use of a single male-sterile H. petiolaris Nutt. cytoplasm. So far, only eight CMS sources were derived from wild perennials, and fertility restoration had been studied in two of them. We report here the identification of a new cytoplasmic male sterility from H. giganteus (CMS-GIG3) and its corresponding fertility restoration genes. This CMS source has the characteristic male sterility; no extruding anthers and no pollen production and had full fertility when crossed with cultivated line HA 89. Fertility restoration genes were not found among 19 cultivated sunflower lines tested but were found in four interspecific amphiploids. Inheritance study suggested single dominant gene control of fertility restoration, which can be easily incorporated into line for hybrid production.
Technical Abstract: Helianthus giganteus L.-1934 was crossed with cultivated line HA 89 and colchicine-treated to induce chromosome doubling. One of the 12 F1 plants was male-sterile and was pollinated by HA 89 several times to produce CMS progeny with 2n=34. BC4F1 plants were pollinated with 19 cultivated restoration tester lines in 2001, but progenies grown in the field in 2002 failed to produce any male-fertile plants. Then BC5F1 plants were pollinated by interspecific amphiploids involving seven perennial Helianthus species in 2002. Male-fertile progeny were identified from amphiploids involving H. maximiliani, H. grosseserratus, H. angustifolius, and H. atrorubens. Results suggest an abundance of fertility restoration genes in perennial wild species and the convenience of using interspecific amphiploids when searching for additional Rf genes. One exceptional and very rare F1 plant of CMS H. giganteus // H. maximiliani / HA 89, amphiploid had 2n=34, and its F2 male-fertile to male-sterile segregation pattern fit a 3:1 ratio well, indicating single dominant gene control of fertility restoration.