Four-llele combinations for high oleic, low linolenic soybeans

Authors: Hudson, Karen; Carrero-Colon, Militza

Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/20/2024
Publication Date: 12/5/2024
Citation: Hudson, K.A., Carrero-Colon, M. 2024. Four-llele combinations for high oleic, low linolenic soybeans. Journal of the American Oil Chemists' Society. https://doi.org/10.1002/aocs.12925.
DOI: https://doi.org/10.1002/aocs.12925

Interpretive Summary: Soybean oil is valuable as a food oil and a biofuel on a global scale. However, for the best utility and value in these markets, commodity soybean oil must undergo partial hydrogenation or chemical treatments to make the oil more stable. Soybean geneticists have shown that certain genes can be used to elevate levels of oleic acid, and soybean carrying other genes have reduced levels of linolenic acid. In this project, genetic combinations were made (by crossing the plants to one another) to make soybean plants that had both the high oleic and low linolenic traits, and it was demonstrated that this trait was stable over multiple years and did not affect other valuable aspects of the soybean seed (for example, seed protein that is a component of soybean meal). These lines will be a useful new tool for soybean breeders enabling the production of soybean lines with improved oil profiles.

Technical Abstract: Soybean oil accounts for approximately 29% of global oil consumption. The commodity soybean oil profile contains relatively high levels of the polyunsaturated linoleic and linolenic acids, and 20% oleic acid. To make a healthier and more stable soybean oil for food uses, genetic approaches in soybean composition breeding have targeted reducing levels of linoleic and linolenic acid and increasing the oleic acid fraction soybean oil. Quadruple mutants were constructed to evaluate the combinations of fatty acid desaturase2 (fad2) and fatty acid desaturase3 (fad3) mutant alleles to achieve a high oleic, low linolenic soybean oil profile. Over three growing seasons we observed that all four combinations resulted in oleic acid levels from 75%-82%, and linolenic acid levels from 1.9-2.7%. The high oleic and low linolenic traits did not exhibit an additive effect when compared to double mutants homozygous for fad2 mutant alleles or fad3 mutant alleles. No significant differences in seed protein or oil levels were observed in the quadruple mutants, suggesting that these combinations will be useful for breeding soybean with improved oil profiles.