Abstract: In order to introduce HMW-GS genes with good quality properties into high-yielding wheat line 1718 from wheat line Soissons, backcross breeding, PCR-based approach and SDS-PAGE method had been used in wheat segregating progenies grown in field and greenhouse. The results showed that the heredity of the Dx5 gene in random progeny of BC1, BC2, BC3, BC3F1 completely accorded with hereditary rule of a pair of genes and its proportion was 1:1. The plants with Dx5 genes in BC2, BC3, BC3F1, BC3F2 were detected with PCR-based approach, backcrossed and self-inbred after other agronomic characters had been selected. The lines with Dx5 genes were found in BC3F2 progeny by methods as in BC3F2. The morphological characters of line1718-4 were similar to those of the recurrent parent 1718 and also were uniform. 1718-4-6 and 1718-4-10 which carried HMW-GS 1, 7+8, 5+10 were selected from line1718-4 by using SDS-PAGE. Two new lines still retained high-yielding character of their recurrent parent 1718. Their most quality properties were better than that of 1718. The combination of PCR-based approach, SDS-PAGE method with backcross breeding is proposed as a directional, quick, efficient procedure for converging many good HMW-GS genes onto higher yielding lines and improving their genotypes with good quality properties.

Key words: Common wheat, HMW-GSDx5 gene, Molecular marking-assisted selection, Backcross breeding