Instability of the blue grain color in a strain of Triticum aestivum L.

Abstract

The blue-grained wheat accession TRI 2401 (Triticum aestivum var. tschermakianum Mansf.) from the gene bank in Gatersleben was confirmed to be an alien disomic substitution for wheat chromosome 4Aa, which confers blue aleurone. Reciprocal hybrids with 'Chinese Spring' had nonblue (red) seeds in F1 and segregated on average 74% nonblue and 26% blue in F2. This segregation is not necessarily monogenic. In selfed progeny of TRI 2401 about 1.4% of the seeds were nonblue (red). Most of these aberrant seeds were monosomic for the alien chromosome. The seed from selfing of the monosomics segregated in a ratio of 67% nonblue (2n = 41) to 33% blue (2n = 42). The nonblue seeds undoubtedly arose from aneuploid gametes originating by nondisjunction during gametogenesis. Since 20-chromosome male gametes rarely function, it was assumed that the deficiency was mostly transmitted through the egg cells. In addition, spotting of the blue aleurone was observed with a frequency of 0.017%. Size and pattern of the spots varied considerably. It is thus likely that the loss of the blue color in the aleurone cells resulted from the loss of the alien chromosome during endosperm development. On the basis of the behavior mentioned, it was concluded that the gene(s) for blue aleurone in the European wheat accession TRI 2401 seem to be different from the analogous gene, Ba, in the blue-grained derivatives of wheat × Elytrigia pontica crosses.Key words: Triticum aestivum var. tschermakianum, blue aleurone, 4Aa substitution, color spots.

Molecular Cytogenetics of an Amphiploid Trigeneric Hybrid betweenTriticum durum,Thinopyrum distichumandLophopyrum elongatum

“…Hybrids between Triticeae species often show phenotypic or developmental instabilities, some similar to those induced by transposon activity in Zea mays, but of various origin (e.g. Mettin, Schlegel and Lehmann, 1991). This phenomenon was also found in pure species (e.g.…”

Development of dominant nuclear male‐sterile lines with a blue seed marker in durum and common wheat

“…Blue kernel colour is a morphological marker of Elytrigia elongata (Host) Nevski. Some wheat lines with substitution chromosomes or additional chromosomes from E. elongata also have a blue kernel colour (Hurd 1959, Li et al 1982, Mettin et al 1991, Zeller et al 1991. Since mono-chromosomes with partial homology tend to pair partially, segment breaks or misdisjunction sometimes occurs.…”