C-banded karyotypes and polymorphisms in hexaploid oat accessions (Avena spp.) using Wright's stain.

A chromosome C-banding protocol using Wright's stain was employed to compare chromosomes in cultivars and wild accessions of several hexaploid oat taxa (Avena spp.). This technique permits the identification of each of the 21 somatic hexaploid oat chromosomes. Digital images of C-banded cells were captured on computer and used to construct karyotypes of several oat accessions. Polymorphisms for C-bands among oat cultivars and wild accessions are described. These banding polymorphisms can be used to trace introgression of chromosomes from wild sources and to provide physical markers on the genetic map for oat. Although C-banding permits the identification of likely C-genome chromosomes based on comparisons with C-banding patterns in diploid and tetraploid Avena species, the A and D genomes cannot be readily differentiated based on their banding patterns.