Combination of Novel Mutation in FAD3C and FAD3A for Low Linolenic Acid Soybean

Abstract

Core Ideas New low linolenic soybean with novel alleles of FAD3A and FAD3C. Mutation in GmFAD3C reduces linolenic acid levels. Soybean FAD3C controls linolenic acid levels. Conventional commodity soybean oil can typically have levels of linolenic acid up to 8% of the total oil fraction. As linolenic acid is unsaturated, unstable, and contributes to off‐flavors, and the hydrogenation process can produce harmful trans fats, genetic alternatives for soybean [Glycine max (L.) Merr.] low in linolenic acid are desirable. We identified a novel mutant allele of the gene encoding the omega‐3 desaturase FAD3C in a screen of a N‐nitroso‐N‐methylurea (NMU)‐mutagenized population. This allele resulted in a 2 to 3% reduction in linolenic acid levels as a fraction of the total fatty acids. We measured the effect of combining this mutation with mutations in the homeologous FAD3A desaturase gene on the soybean fatty acid profile. This FAD3C polymorphism may be useful to breeders seeking conventional approaches to reduce linolenic acid levels. In particular, combinations of mutant alleles of FAD3A and FAD3C result in soybean with linolenic acid comprising only 2 to 3% of the total fatty acids.