Metaphases of the tetraploid wheat, Aegilops ventricosa (2n=4x=28). A colour version of the figure in Daniel Bardsley et al. 1999 Theoretical and Applied Genetics 99: 300-304. Figure 1. In situ hybridization of 45S rDNA (red) and a repetitive DNA sequence dpTa1 (green) to DAPI counterstained metaphase chromosomes of the wild tetraploid (2n=4x=28) wheat Aegilops ventricosa which as D and N genomes. Using the probes, all individual chromosomes, although morphologically very similar, can be identified. Furthermore, notable features of genome evolution are apparent: the major rDNA loci are present on the N genome chromosomes, while the repetitive dpTa1 sequence is much more abundant on the D genome chromosomes, although both genomes presumably originated from a common ancestor. See Bardsley et al. (2000) for further details. Below is a low resolution (130 kb) version of the figure in JPG format. At the bottom, there is a high resolution version of part of the image showing Aegilops ventricosa 2n=4x=24 metapahse stained blue with DAPI, and probed with rDNA (red) and a repeat sequence (green) - a part 1 of the plate below.

In situ hybridization to Aegilops ventricosa metaphases