Identification of Alien Chromosome/Chromatin Introgressions in Triticale × Wheat Derived Stable Lines Through Molecular Cytogenetic Analysis

Abstract

Molecular cytogenetic study was conducted for identifying rye chromosome/chromatin translocation, substitution and addition in 43 triticale x wheat derived stable lines (BC₁F₇ and F₇ generations) six different crosses using FISH (Fluorescence in situ hybridization) and GISH (Genomic in situ hybridization) analyses with different probes. Rye chromosomes/chromatin was identified in 17 BC₁F₇ and 12 F₇ lines by these two analyses. The GISH and FISH techniques worked satisfactorily for identifying the presence of rye chromatin at metaphase. All the lines were associated with alien chromosome translocation, addition or substitution except a few lines. Most of the recombinants present in TW 1, TW 2 and TW 6 crosses were observed to be associated with important alien chromatin translocation like 1BL/1RS, substitutions 1R (1D), 5R (5D) and combination of both i.e., 1BL/1RS + 5R (5D) and in some cases presence of more than 4 rye chromosomes. The crosses TW 3 and TW 5 possessed 8 to 14 rye chromosomes in their chromosome constitution. So, their morphological expression was similar to triticale. These reconstituted lines will be of immense application for the future wheat breeding programmes.