Submitted to: In Vitro Biology Meeting
Publication Type: Proceedings
Publication Acceptance Date: 3/28/2005
Publication Date: 6/3/2005
Citation: Dong, N., Williams, N.T., Mcmahan, C.M., Rath, D., Pearson, C., Cornish, K. 2005. Factors affect agrobacterium-mediated sunflower transformation.. In Vitro Biology Meeting. 41, p. 30-A, Spring 2005.
Interpretive Summary: Sunflower transformation is very difficult. Factors such as genotypes, explants, wounding methods, cysteine, and selection methods were tested to find best protocol for sunflower transformation. Using the proximal parts of the cotyledons of the genotype of #665, infected by Agrobacterium harboring a vector containing a bar gene and a gus gene with intron, sonicated for 2 x 15 seconds, and included 400-mg/L cysteine in both inoculation solution and co-culture medium. Three independent GUS positive shoots have been obtained.
Technical Abstract: Sunflower is a recalcitrant plant species for transformation. Mature seeds from seven genotypes were tested and #665 had the highest regeneration efficiency. To test different methods in attempts to increase the transformation efficiency, a vector containing the bar gene and the gus gene with an intron was used. Different explants including half apexes and proximal parts of the cotyledons were tested. Different wounding methods such as bombardment, shaking with glass beads, and sonication, also were tested. The effect of cysteine was examined. Shoots developed from explants were selected by their resistance to the herbicide ammonium-glufosinate. The best result was obtained when using proximal parts of the cotyledons, sonicated for 2 x 15 seconds, and inclusion of 400 mg/L cysteine in both inoculation solution and co-culture medium. Three independent GUS positive shoots have been obtained.