Inheritance of Reduced Stearic and Palmitic Acid Content in Sunflower Seed Oil

Reducing the saturated fatty acid content of sunflower (Helianthus annuus L.) oil would benefit the sunflower industry through increased consumer preference for a low saturated sunflower product. This study was conducted to determine the inheritance of low stearic and low palmitic acid content found in three sunflower mutant lines treated with two mutagens, N-nitroso-N-methylurea (NMU) and ethyl methanesulfonate (EMS) at rates of 1 and 2 g kg⁻¹. The fatty acid content of approximately 6800 M₅ lines was analyzed by gas chromatography. Two M₅ lines, HA 821 LS-1 and RHA 274 LS-2, had lower stearic acid content (41 and 20 g kg⁻¹), and one M₅ line, RHA 274 LP-1, had lower palmitic acid content (47 g kg⁻¹) than their respective parental lines. Segregation ratios of F₂ and testcross progeny indicated that the low stearic acid content in HA 821 LS-1 was controlled by one gene, designated fas1, with additive gene action. The low stearic acid content in RHA 274 LS-2 was controlled by two genes with additive gene action. The first gene was designated fas2, and the second gene was temporarily designated fasx. The allele fap1 was identified in RHA 274 LP-1 to control low palmitic acid content with additive gene action. The combination of the alleles for low stearic and low palmitic acid content identified in this study could reduce the total saturated fatty acid content of oil in sunflower from 130 g kg⁻¹ to less than 80 g kg⁻¹. Cooperative investigation between the USDA-ARS and the North Dakota Agric. Exp. Stn., Fargo, ND 58105. Research was supported in part by a grant from the North Dakota Agricultural Products Utilization Commission. Mention of a proprietary product does not constitute a recommendation or warranty of the product by the USDA or North Dakota State University and does not imply approval to the exclusion of other suitable products.