Genetic Control of Glaucousness in Wheat Plants

Abstract

Genetic control of the inheritance of the “presence/absence of glaucousness on vegetative plant organs” trait was studied in di-, tetra-, and hexaploid wheats. Out of 284 studied accessions of diploid (2n = 14) wheat Triticum urartu Thum. ex Gandil., no accessions with glaucousness were found. A monogenic control of the absence of glaucousness in Aegilops squarrosa L. (D genome donor of hexaploid wheats) was demonstrated. Among 730 accessions of tetraploid (2n = 4x = 28) wheat T. durum Desf. from the ICARDA collection, 19 non-glaucous accessions were detected. It was demonstrated that the “glaucouslessness” trait in these accessions is controlled by the allelic dominant gene. Using the D-genome chromosomal substitution lines of the Langdon cultivar, this gene was localized in the chromosome 2B, and it was suggested that this is the Iw1 dominant glaucousness inhibitor gene. A previously not described recessive gene determining the glaucouslessness in tetraThatcher (tetraploid (2n = 4x = 28) form of Canadian cultivar of hexaploid (2n = 6x = 42) common wheat Thatcher) was found. Using the line with the 2BS-1, 2BS-3, and 2BS-11 deletions of the cultivar Chinese Spring, the w1 gene, which causes the presence of glaucousness in the common wheat, was physically mapped in the proximal part of chromosome 2B before the break point of 0.53.