Genomic analysis in the genus Aegilops. II. Interspecific hybrids between polyploid species sharing two common genomes

Abstract

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 Ac. 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) XAe. 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.

Phylogenetic analysis of C, M, N, and U genomes and their relationships with Triticum and other related genomes as revealed by LMW-GS genes at Glu-3 loci

“…The existence of polyploid species such as Aegilops ventricosa (DDNN) and Aegilops juvenalis (DDMMUU) showed that the D genome could form intergenomic combinations with the N and M genomes. It was shown that in most cases the divergences between the shared genomes (U, D, or C) in different tetraploid species (Cuñado 1993a) and D, U, M, and N in hexaploid species (Cuñado 1993b) of Aegilops are, at present, substantial despite their common origin. Phylogenetic relationships among C, M, N, U, and common wheat genomes are shown in Figs.…”