This invention relates to methods of identifying and/or selecting soybean plants or germplasm that display improved antibiosis and/or antixenosis resistance to one or more biotypes of soybean aphid. In certain examples, the method comprises detecting at least one Rag haplotype that is associated with improved soybean aphid resistance. In other examples, the method further comprises detecting a marker profile comprising two or more Rag haplotypes.
