Speciation of polyploid wheat represents a classic example of successful speciation via allopolyploidy, which contains two sequential allopolyploidization events: at the tetraploid level to form emmer wheat (Triticum turgidum) and at the hexaploid level to form common wheat (T.aestivum).Although the evolutionary trajectories of both allopolyploidization events can be largely recapitulated in the laboratory, the immediate chromosomal and molecular consequences of allopolyploidization in wheat still remain poorly understood.