Characterization of New Allelic Combinations for High‐Oleic Soybeans

Abstract

A soybean line with elevated levels of oleic acid was identified in a forward genetic screen. The causative mutation was identified and the line contained a C to T transition mutation causing a novel amino acid substitution in FAD2‐1B, a gene that encodes an enzyme critical for soybean fatty acid biosynthesis. Alone, this fad2‐1b mutation resulted in a 30% increase in seed oleic acid levels. Double mutant combinations with four previously isolated mutant alleles of the FAD2‐1A gene were produced to determine the synergistic effects of mutation in both genes on oleic acid levels in seeds. In all instances, mutant alleles of FAD2‐1A and FAD2‐1B combined to produce seed containing over 70% oleic acid in the oil fraction. These lines provide a new germplasm resource that could be used to create high oleic soybeans through conventional breeding approaches.