Characterization of Three Novel High Stearic Acid Soybean Lines.

Soybean [Glycine max (L.) Merr.] is the most widely produced oil seed crop in the world, accounting for over half of worldwide oil crop production.  Soybean oil naturally high in stearic acid would be useful for solid fat applications; however, stearic acid content in soybean typically represents only 2%-4% of total oil.  The objectives of this study were to 1) to identify loci responsible for variation in stearic acid and 2) to study the effect of these loci on agronomic characteristics, such as seed emergence, yield, and total oil.  Three different ‘Holladay’ mutants with high stearic acid, was crossed to either FAM-94-41 or a FAM-94-41-dervied line carrying a point mutation in a seed-specific isoform of a Δ9–stearoyl-acyl carrier protein-desaturase (SACPD-C).  Fatty acid analysis was performed over two growing seasons with F₂-derived lines and transgressive segregation for stearic acid content was observed in all four populations.  SACPD isoform sequencing and selective genotyping using the 1536 SNPs of the Universal Soybean Linkage Panel were used to map the loci responsible for variation in stearic acid content.