|PHAM, ANH-TUNG - University Of Missouri|
|LEE, JEONG-DONG - Kyungpook National University|
|SHANNON, GROVER - University Of Missouri|
Submitted to: BMC Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/2/2010
Publication Date: 9/10/2010
Citation: Pham, A., Lee, J., Shannon, G., Bilyeu, K.D. 2010. Mutant alleles of FAD2-1A and FAD2-1B combine to produce soybeans with the high oleic acid seed oil trait. Biomed Central (BMC) Plant Biology. 10:195.
Interpretive Summary: Commodity soybeans are poised to undergo a revolutionary change. Major shifts in market expectations for the nutritional quality of the oil, brought about in part through food labeling requirements and the suitability for biodiesel, are driving the commodity soybean to embrace new seed compositional qualities. Using conventional soybean breeding technology without transgenics, we created novel combinations of two genes responsible for the accumulation of oleic acid in soybean seed oil to develop soybean seeds with the high oleic acid trait. The trait was stable across three environments and could be efficiently incorporated into new lines to accelerate soybean variety development. The impact of this research is the availability of technology to create high oleic acid soybean cultivars that can meet the expectations of the new commodity oil market.
Technical Abstract: The alteration of fatty acid profiles in soybean [Glycine max (L.) Merr.] to improve soybean oil quality is an important and evolving theme in soybean research to meet nutritional needs and industrial criteria in the modern market. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition, flavor and oxidative stability of the oil. The objective of this work was to create the high oleic acid trait in soybeans by identifying and combining mutations in two omega-6 fatty acid desaturase genes, FAD 2-1A and FAD 2-1B. Soybean plant introduction (PI) germplasm lines that contained elevated oleic acid content in the seed oil were characterized for the sequence and genetic association of their FAD 2-1A and FAD 2-1B alleles. Three polymorphisms found in the FAD 2-1B alleles of two soybean lines resulted in missense mutations. For each of the two soybean PI lines, there was one unique amino acid change within a highly conserved region of the protein. The sequence polymorphisms were developed into highly efficient molecular markers for the mutant alleles. The mutant FAD 2-1B alleles were associated with an increase in oleic acid levels, although the FAD 2-1B mutant alleles alone were not capable of producing a high oleic acid phenotype. When existing FAD 2-1A mutations were combined with the novel mutant FAD 2-1B alleles, a high oleic acid phenotype was recovered only for those lines which were homozygous for both of the mutant alleles. The high oleic acid soybean germplasm developed contained a desirable fatty acid profile, and it was stable in multiple environments. The resources described here for the creation of high oleic acid soybeans provide a framework to efficiently develop soybean varieties to meet changing market demands.