Characterization and Deployment of the High Stearic Acid Soybean Oil Trait
Crop Production and Pest Control Research
Project Number: 5020-21000-007-03
Start Date: Oct 01, 2013
End Date: Sep 30, 2015
The objectives of the full proposal are to develop and evaluate the agronomic potential of soybean lines with high (>20%) levels of stearic acid in the seeds. It has been demonstrated that the SACPD-C gene controls stearic acid levels. Current soybean germ-plasm with the elevated stearate trait carries a large chromosomal deletion (which includes the SACPD-C gene) and exhibits poor yield. Our sub objectives are to 1. Evaluate yield in six SACPD-c missense mutants that contain 11-14% stearic acid in seeds 2. Map and characterize six to seven unknown genetic loci that contribute to high stearic acid levels 3. Combine SACPD-C mutant alleles with the other unknown genes to increase stearic acid levels above 20%, and evaluate the agronomic potential of these lines as well as the environmental stability of this trait 4. Combine high stearate lines with mutations that cause low linoleic acid in soybean seed.
To determine the phenotypes of the high stearate mutant combinations and the high stearate-low linolenate combinations, double mutants will be created by genetic crossing and advancement of the progeny to the F2 stage. Yield and other agronomic observations will be performed on F3 lines from these crosses in multiple locations. To determine the identity of the unknown genes, candidate gene sequencing, genotyping by sequencing and genetic mapping will be used. Bulk segregate mapping will be used on an existing population segregating for 20% stearic acid (known SACPD-C mutant plus another locus). Up to 6 additional mapping populations will be advanced in the winter nursery, and will be genotyped, phenotyped, and mutations causing elevated stearate will be genetically mapped.