关键词: 六倍体小麦, 单核苷酸多态性, 等位基因特异PCR, 碱基错配

Abstract: 【Objective】Two hexaploid wheat cultivars (Triticum aestivum L.), Opata85 and W7984, their 111 recombinant inbred lines (RILs), and three diploid relative-species, T. urartu, Ae. Speltoides and Ae. Tauschii were used as plant materials to study the method of assaying single nucleotide polymorphism with allele-specific PCR in wheat. 【Method】 Two SNPs were discovered on B genome by aligning the TaDREB1 genes in two hexaploid wheat cultivars and three diploid relative-species. To type these SNPs, allele-specific primers and their complementary primers were designed using the SNPs as their 3′-end. In addition, we studied the effect of the mismatched bases at the 3′-end of the allele-specific primers on PCR and the optimum PCR system. 【Result】There were distinct effects of the mismatched bases at 3′-end different sites of the allele-specific primers on allele-specific PCR, so did different types of mismatched bases. Moreover, the concentrations of Mg2+, dNTP and Taq DNA polymerase in allele-specific PCR were higher than that in conventional PCR. 【Conclusion】It is feasible to assay SNPs by allele-specific PCR in hexaploid wheat, as long as proper mismatched bases were introduced at 3′-end proper sites of the allele-specific primers and the PCR system was optimized reasonably.

Key words: Hexaploid wheat, Single nucleotide polymorphism, Allele-specific PCR, Mismatched base