Physical mapping of a 7A.7D translocation in the wheat–Thinopyrum ponticumpartial amphiploid BE-1 using multicolour genomic in situ hybridization and microsatellite marker analysis

Abstract

The absence of chromosome 7D in the wheat-Thinopyrum ponticum partial amphiploid BE-1 was detected previously by multicolour genomic in situ hybridization, sequential FISH (fluorescence in situ hybridization) using repetitive DNA probes, and SSR marker analysis. In the present study the previous cytogenetic and SSR marker analyses were expanded to include 25 other SSR markers assigned to wheat chromosomes 7A and 7D to confirm the presence of a 7A.7D translocation and to specify its composition. An almost complete chromosome 7A and a short chromosome segment derived from the terminal region of 7DL were detected, confirming the presence of a terminal translocation involving the distal regions of 7AL and 7DL. In both cases the position of the translocation breakpoint was different from that of known deletion lines. The identification of the 7AL.7DL translocation and its breakpoint position provides a new physical landmark for future physical mapping studies, opening up the possibility of more precise localization of genes or molecular markers within the terminal regions of 7DL and 7AL.

Production and Molecular Cytogenetic Identification of Wheat-Alien Hybrids and Introgression Lines

“…On the basis of their multicolour FISH patterns, the alien chromosomes could be arranged in eight pairs and could also be unequivocally differentiated from each other (Sepsi et al 2008). In situ hybridization techniques, combined with SSR marker analysis, are extremely useful in detecting and identifying intergenomic rearrangements in the wheat genome, leading to the selection of genetic materials that could be useful for future mapping studies (Somers et al 2004;Sepsi et al 2009). …”

Plant Breeding from Laboratories to Fields

“…The Triticeae wild relatives continue to be important sources of genes for introducing agronomically desirable traits into common wheat and durum wheat (Triticum durum) [20][21]. Thus, alien gene transfer into common wheat via cross-species hybridization makes possible the resistance increasing to biotic and abiotic stresses as well as the quality improving [22][23]. Several species such as of the genera Aegilops, Secale and Thinopyrum have been extensively used in hybridizations with common wheat, thus proving to be a valuable source of genes [3,[24][25].…”

Genomic in situ Hybridization in Triticeae: A Methodological Approach

“…Thus, alien gene transfer into common wheat via cross-species hybridization makes possible the resistance increasing to biotic and abiotic stresses as well as the quality improving [22][23]. Several species such as of the genera Aegilops, Secale and Thinopyrum have been extensively used in hybridizations with common wheat, thus proving to be a valuable source of genes [3,[24][25].…”