Seed Chemical Composition Variability and FAD2A Functional SNP Genotypes in the U.S. Peanut Mini-Core Collection.

Peanut seeds are nutritious containing high amounts of oil and protein as well as some useful phytochemicals which can contribute to human health. The U.S. peanut mini-core collection is an important genetic resource for improving seed quality and developing new cultivars. Variability of seed chemical composition within the mini-core was assessed from freshly harvested seeds of 102 accessions in a replicated field study over two years. Oil, fatty acid composition, flavonoid, and resveratrol content were quantified by NMR, GC, and HPLC, respectively. Significant variability was detected in seed chemical composition among accessions and botanical varieties. Accessions were further genotyped with a functional SNP marker from the FAD2A gene using real-time PCR and classified into three genotypes with significantly different O/L ratios. The results from real-time PCR genotyping and GC fatty acid analysis were consistent. Accessions with high amounts of oil, quercetin, high seed weight, and O/L ratio were identified. The results from this study may be useful not only for peanut breeders, food processors, and product consumers to select suitable accessions or cultivars, but also to potentially expand the mini-core collection variability to include a better representation of the peanut genetic resources.