The Russian wheat aphid,Diuraphis noxia, is a serious pest of wheat grown in the summer rainfall regions of South Africa. The use of D.noxiaresistant cultivars may reduce the impact of this pest on cereal production, at the same time reducing environmental risks and minimizing control costs. The objective of the study was to determine the inheritance of D.noxiaresistance present in the lines OSU ID 2808 (Triticum aestivum)and Aus 22498 (Triticum aestivumvar.vavilovi)in order to ensure their judicious use in a backcross breeding programme. Resistant lines OSU ID 2808 and Aus 22498 were crossed with the susceptible cultivar Tugela after being screened withD. noxia.Resistance reactions of the F1, BC1and F2plants, and individual F2plant derived F3families indicated that the resistance in both genotypes is controlled by single dominant genes. It is unknown whether these genes are identical to any known, designated resistance genes or each other.