Identifying FATB1a deletion that causes reduced palmitic acid content in soybean N87-2122-4 to develop a functional marker for marker-assisted selection

Abstract

Palmitic acid is a major saturated fatty acid in soybean oil, and consumption of saturated fat is linked to a risk of coronary diseases. Development of soybean (Glycine max) cultivars with reduced palmitic acid content is an important goal of soybean breeding. The FATB1a gene was previously found to be responsible for reduced palmitic acid in the soybean line N87-2122-4. The objective of this research was to characterize the FATB1a gene identified in N87-2122-4 and develop a breeder-friendly, functional marker to facilitate marker-assisted selection and improve breeding efficiency for reduced palmitic soybeans. With the availability of soybean genetic maps, reference genome, and gene annotations, an approximate 254 kb deleted genomic region, including the FATB1a gene, was identified. Based on the gene deletion information, we developed a TaqMan marker and tested it with a segregating F 2 population that consisted of 140 individual plants derived from ‘Cook’ × N87-2122-4. The marker performed well and accounted for 57 % of the phenotypic variation. The marker was also validated using a panel of 121 diverse soybean lines with known fatty acid profiles. The result indicated that the marker can be used effectively in marker-assisted breeding for reduced palmitic acid in soybean.