single nucleotide polymorphism linked to the quantitative trait locus of soybean cyst nematode resistance

We previously mapped four unlinked restriction fragment length polymorphism (RFLP) markers associated with soybean cyst nematode (SCN) resistance. The partial coefficient of determinations (R2) of the major quantitative trait locus (QTL) A006 is 91%. A single nucleotide polymorphism (SNP) linked to the major QTL of soybean cyst nematode resistance was detected by comparing sequences amplified from "Hartwig," a broad-based SCN resistant line, and "Williams 82," an SCN susceptible line. The SNP was validated using SCN bioassay data at Purdue University. This SNP is located within the site of Fau I, which makes it possible to distinguish resistant allele T from susceptible allele C by PCR followed by Fau I digestion. The discovery of this SNP and its easy detection are of significant importance to plant breeders and to quality assurance managers.