Analysis of metaphase I chromosome association in species of the genus Aegilops
- N. Cuñado
- Theoretical and Applied Genetics
Hybrids between polyploid Aegilops species sharing two common genomes were analysed at metaphase I by using a C-banding technique in order to establish genome relationships. In all cases it allowed discrimination between associations of chromosomes with similar morphology and C-banding belonging to the same genomes (homomorphic associations) and associations involving different chromosomes (heteromorphic associations). In the hybrids involving Ae. variabilis and Ae. kotschyi, (UUSS), it was also possible to identify the U and S genomes, which are shared by the tetraploid species, and their analysis indicated that the genomes of both species are essentially unaltered. However, the data of the Ae. crassa(6x) x Ae. vavilovii (DDDMMN) hybrid showed that the divergences between the shared genomes are at present substantial despite their common origin. By contrast, in the case of the Ae. triaristata(6x) x Ae. triaristata(4x) (UUMMN) hybrid the data did not confirm that the hexaploid species arose from the tetraploid one.