|THAPA, RIMA - Purdue University|
|ADDO-QUAYE, CHARLES - Purdue University|
|HELD, JAMES - Purdue University|
|DILKES, BRIAN - Purdue University|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/6/2017
Publication Date: 1/4/2018
Citation: Thapa, R., Carrero-Colon, M., Addo-Quaye, C., Held, J., Dilkes, B., Hudson, K.A. 2018. New alleles of FAD3A confer reduced linolenic acid trait to soybean seeds. Crop Science. 58(2):713-718. https://doi.org/10.2135/cropsci2017.08.0490.
Interpretive Summary: Soybean seed is a source of oils used in biofuels, industrial lubricants, and fats for human consumption. Linolenic acid is a component of soybean oil that reduces the shelf-life and stability of the oil. As chemical methods to remove linolenic acid from soybean oil can result in the creation of unhealthy trans fats in the oil, identifying genes that reduce seed linolenic acid is an important goal for soybean breeding. In this study, the authors have identified three new genetic variants of the FAD3A gene, that function to reduce levels of linolenic acid in soybean oil. These alleles can be used alone or in conjunction with other mutations to breed soybeans with an improved oil profile.
Technical Abstract: Soybean [Glycine max (L.) Merr.] is one of the most important sources of plant-based oil worldwide. Linolenic acid is associated with undesirable flavors and poor stability in soybean oil. Partial hydrogenation is typically used to reduce the levels of linolenic acid in soybean oil, however this process results in the production of trans fatty acids. Studies have shown increased risk of coronary heart disease being linked to trans fatty acids present in hydrogenated oils. Thus it is crucial to seek out different routes to develop soybean lines with lower linolenic acid. To identify novel and useful alleles that could help reduce levels of linolenic acid in soybean, we screened a chemically mutagenized population. Three lines with reduced levels of linolenic acid in seed were identified. Mutant lines contained 3.8 to 4.5% of the total fatty acids as linolenic acid, and carry independent mutations in the FAD3A gene encoding a desaturase responsible for the conversion on linoleic acid to linolenic acid in soybean seeds. In order to follow the mutant alleles in segregating population, mutant specific markers were developed and the genetic association was confirmed with the reduced level of linolenic acid. These soybean lines will serve as a source of reduced linolenic acid to meet the breeding objectives providing improved soybean lines.