Abstract: TaDREB1 is a key transcription factor controlling abiotic-stress-responsive gene expression. Twenty hexaploid cultivars and three diploid species of wheat relative were used to detect single nucleotide polymorphisms (SNPs) in TaDREB1 gene based on sequencing. A total of 271 SNPs and 14 InDels (insertion and deletion) were identified from 38 038 bp nucleotide sequence of TaDREB1, on average of one SNP every 140 bp and one InDel every 2 717 bp. The nucleotide diversity value in the hexaploid (Л=0.01029) was lower than that in the diploid (Л=0.02188). This indicated that diversity of TaDREB1 gene in the diploid was larger than hexaploid due to stronger selection pressure loaded on the hexaploid than diploid. The result of haplotype analysis revealed that SNPs in TaDREB1 were correlated with drought-tolerant character. Two haplotypes including one drought-tolerant accession and one non-drought-tolerant accession were also found, respectively. This showed the complicacy of drought-tolerance and the complicated drought-tolerant phenotype can't be account for only based on the single nucleotide polymorphisms in TaDREB1 gene.

Key words: Wheat, TaDREB1 gene, Single nucleotide polymorphism, Nucleotide diversity, Drought torlerance, Haplotype