REGISTRATION OF SEVEN CYTOPLASMIC MALE-STERILE AND FOUR FERTILITY RESTORATION SUNFLOWER GERMPLASMS

Authors: Jan, Chao-Chien; Vick, Brady

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2006
Publication Date: 7/1/2006
Citation: Jan, C.C., Vick, B.A. 2006. Registration of seven cytoplasmic male-sterile and four fertility restoration sunflower germplasms. Crop Science. 46:1829-1830.

Interpretive Summary: Seven cytoplasmic male-sterile lines, cms ANN14, cms MUT7, cms MUT8, cms MUT9, cms MUT10, cms MUT11, and cms MUT12, and four corresponding fertility restoration lines, Rf Armavir, Rf PI 432513, Rf VNIIMK, and RF P21, 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 PET1 (French) cytoplasm 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.

Technical Abstract: 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 'Armavir', 'VNIIMK', 'P21', and male-fertile plants of PI 432513. 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 self-pollinated 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 mutation, with respective designations of cms 45-1, cms 139-1, cms 491-1, cms 515-1, cms 555-1, and cms 3149. 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 this release. Cms ANN14 and cms MUT 7 through cms MUT12 are also completely restored by RHA266, RHA274, RHA280, and RHA296, and their F2 segregation ratios indicate a single dominant gene control, implying a common cytoplasmic male sterility similarity in all lines and that Rf1 was a factor in their restoration. 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. 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.