Abstract: Wheat bread-making quality is associated with allelic pairs at the Glu-D1 complex locus, designated 1Dx5-1Dy10 and 1Dx2-1Dy12, respectively. The specific PCR marker of 1Dx5 was applied to detect the presence of the HMW-glutenin 1Dx5 gene in 49 wheat varieties. The results showed that the PCR marker could amplify a 450bp fragment in 17 varieties and the positive control, Cheyenne, comprising the 1Dx5 gene, while other 32 varieties and the negative control did not show the specific product. The results suggested that this PCR marker of 1Dx5 could identify the presence of the HMW-glutenin 1Dx5 gene. The low proportion containing the HMW-glutenin 1Dx5 gene in the 49 wheat varieties implied that the application of the good bread wheat varieties or elite HMW-glutenin subunits in breeding program should be improved. Also the results corresponding to those by protein SDS-PAGE indicated that this marker was reliable and effective. Six BC1F1 populations derived from backcrosses of common wheat lines were screened by this molecular marker and individual plants with the HMW-glutenin 1Dx5 gene were identified.

Key words: Wheat breeding, Wheat HMW-glutenin 1Dx5, PCR marker