ISOLATION AND CHARACTERIZATION OF WHEAT-RYE RECOMBINANTS INVOLVING CHROMOSOME ARM 1DS OF WHEAT

The introgression of genetic material from alien species is assuming increased importance in wheat breeding programs. One example is the translocation of the short arm of rye chromosome 1 (IRS) onto homoeologous wheat chromosomes, which confers disease resistance and increased yield on wheat. However, this translocation is also associated with dough quality defects. To break the linkage between the desirable agronomic traits and poor dough quality, recombination has been induced between 1 RS and the homoeologous wheat arm 1 DS. Seven new recombinants were isolated, with five being similar to those reported earlier and two having a new type of structure. All available recombinants were characterized with DNA probes for the loci Nor-R1, 5SDna-R1, and Tel-R1. Also, the amount of rye chromatin present was quantified with a dispersed rye-specific repetitive DNA sequence in quantitative dot blots. Furthermore, the wheat-rye recombinants were used as a mapping tool to assign two RFLP markers to specific regions on chromosome arms 1DS and 1RS of wheat and rye, respectively.