Fig. 5.

Evidence for recurrent recombination between homoeologous chromosomes in some genotypes of bread wheat. a Examples of suspected double inter-homoeologue recombination events. Heatmap showing coverage of normalised exome capture reads mapped on the CS genome. Values are calculated in 500 kb bins. Location of primers are indicated and shown in more detail in: b Scheme of primers designed for PCR amplification across the suspected translocation breakpoint, which was within gene TraesCS1D03G1023600. c 1.2% agarose gel loaded with PCR products. d GISH on mitotic metaphase chromosome spreads prepared from root tips of wheat line Odesskaia 16. Genomic DNA probes of T. urartu (green) Ae. tauschii (red) and Ae. speltoides (blue) were applied to detect A, B and D genomes, respectively. Chr. 1D (white arrows) showing a terminal segment of A genome origin (green) is also enlarged in the top left. The known 4A/7B translocation is seen by a terminal segment of B genome origin (blue), and the introgression of Ae. markgrafii origin on Chr. 2D is seen by blue/green colour on the terminal segment of the long arm. e Schematic model of reciprocal translocations between homoeologues, starting with a heterozygous, single inter-homoeologue translocation carrier. Translocation is illustrated between chromosomes of the A and D genomes. Further recombination generates recombined chromosomes. Chromosome structure, as seen in Odesskaia 16, is shown with a dotted rectangle