Patent ID: 8692053

Claim:
A method for reliably and predictably introgressing soybean Aphis glycines resistance conferred by a Rag2 gene into non-resistant soybean germplasm or less resistant soybean germplasm comprising: providing a first soybean germplasm that has resistance to Aphis glycines conferred by said Rag2 gene; providing a second soybean germplasm that lacks said resistance; crossing the first soybean germplasm with the second soybean germplasm to provide progeny soybean germplasm; analyzing said progeny germplasm by marker-assisted selection (MAS) to: determine the presence of Rag2 resistance to Aphis glycines by detecting a resistance to Aphis glycines (Rag2) locus that maps to soybean linkage group F of said soybean germplasm, wherein said Rag2 locus is flanked on opposite sides by markers Soyhsp176 and Satt510, and wherein the Rag2 locus comprises allelic DNA sequences that control resistance to Aphis glycines ; and determine the presence or absence of said allelic sequences linked to the Rag2 gene coding for resistance to Aphis glycines in said germplasm; wherein the presence or absence of said allelic sequences linked to said gene is determined by identifying a region of DNA that displays allelic variation between said first and second soybean germplasm linked to said Rag2 locus; and determining that said gene coding for Rag2 resistance is present in said soybean germplasm when said region of DNA comprises a polymorphism linked to Rag2 resistance and present in PI 200538; and determining that said gene is not present in said germplasm when said region of DNA does not comprise said polymorphism linked to Rag2 resistance and present in PI 200538; and selecting progeny that tests positive for the presence of Rag2 resistance to Aphis glycines as being soybean germplasm into which germplasm having Rag2 resistance to Aphis glycines has been introgressed.