Induction of recombination between rye chromosome 1RL and wheat chromosomes.

The ph1b mutant in bread wheat has been used to induce homoeologous pairing and recombination between chromosome arm 1RL of cereal rye and wheat chromosome/s. A figure of 2.87% was estimated for the maximal frequency of recombination between a rye glutelin locus tightly linked to the centromere and the heterochromatic telomere on the long arm of rye chromosome 1R in the progeny of ph1b homozygotes. This equates to a gametic recombination frequency of 1.44%. This is the first substantiated genetic evidence for homoeologous recombination between wheat and rye chromosomes. No recombinants were confirmed in control populations heterozygous for ph1b. The ph1b mutant was also observed to generate recombination between wheat homoeologues.