A novel soybean germplasm with elevated saturated fatty acids

Two soybean [Glycine max (L.) Merr.] germplasm lines have been identified for unique fatty acid content. The very high content of palmitic acid in HPKKJ10 is controlled by the fap₂ and fapx loci, and the very high content of stearic acid in M25 is controlled by the st₂ locus. If the fap₂ and fapx loci are independently inherited from the st₂ locus, soybean germplasm could be developed with more unique and useful combinations of these fatty acids. The objectives of this study were to combine the loci of high palmitic and stearic acids, and determine the effects of altered contents of palmitic and stearic acids on other fatty acids. HPKKJ10 was reciprocally crossed to M25. The data from F₂ seed indicated that the fap₂ and fapx loci controlling high palmitic acid were independently inherited from the st₂ locus controlling high stearic acid. Thus, the germplasm (HPS) with the very high palmitic acid trait from HPKKJ10, and very high stearic acid trait from M25, was easily developed. The increases in palmitic acid due to the fap2 and fapx loci in HPKKJ10, and the increases in stearic acid due to the st₂ locus in M25 were individually associated with changes in oleic acid. The combined increases in these two fatty acids in HPS were associated with decreases in oleic and linoleic acids, and increases in linolenic acid. The development of HPS with high content of saturated fatty acids could open new markets for soybean oil.