Development of a complete set of Triticum aestivum-Aegilops speltoides chromosome addition lines

Aegilops speltoides Tausch (2n = 2x = 14, SS) is considered as the closest living relative of the B and G genomes of polyploid wheats. A complete set of Triticum aestivum L. cv Chinese Spring-Ae. speltoides whole chromosomes and seven telosomic addition lines was established. A low pairing accession was selected for the isolation of the chromosome addition lines. Except fo r chromosomes 3S and 6S, which are presently only available as monosomic ad ditions, all other lines were recovered as disomic or ditelosomic additions . The individual Ae. speltoides chromosomes isolated in the wheat backgroun d were assayed for their generic effects on plant phenotype and cytological ly characterized in terms of chromosome length, arm ratio, distribution of marker C-bands, and FISH sites using a Ae. speltoides-specific repetitive e lement, Gc1R-1, as a probe. The homoeology of The added Ae. speltoides chro mosomes was established by using a standard set of RFLP probes. No chromoso mal rearrangements relative to wheat were detected.