Cuticular wax production on plant surfaces confers a glaucous appearance and plays important roles in plant stress tolerance. Most common wheat cultivars, which are hexaploid, and most tetraploid wheat cultivars are glaucous; in contrast, a wild wheat progenitor, Aegilops tauschii, can be glaucous or non-glaucous. | The cuticular wax inhibitor locus Iw2 in wild diploid wheat Aegilops tauschii Phenotypic survey genetic analysis and implications for the evolution of common wheat