QTL mapping of quality related traits in peanut using whole-genome resequencing

Whole-genome resequencing of a RIL population of 318 lines was performed to construct a high density linkage map and identify QTLs for peanut quality. The map, containing 4561 bin markers, covered a length of 2032.39 cM, with an average marker density of 0.45 cM. A total of 109 QTLs for oil content, protein content, and fatty acid compositions, were mapped on the 18 peanut chromosomes. The QTL qA05.1 was detected in four different environments and displayed a major phenotypic effect on the content of oil, proteins, and six fatty acids. The genomic region spanned by qA05.1, corresponding to a physical interval of ~1.50 Mb, contains two polymorphic SNPs between two parents which could cause missense mutations. The two SNP sites were designed into KASP marker and validated using the lines with extremely high and low oil content, which would be useful in marker-assisted breeding for high oil content peanut varieties.