Allosyndetic recombination between a chromosome of aegilops umbellulata and wheat chromosomes

Abstract

Allosyndetic recombination was induced between chromosome 1U of Aegilops umbellulata and wheat chromosomes by producing plants monosomic for this alien chromosome and homozygous for the mutant ph1b allele, which permits homoeologous chromosome pairing. Recombinants were selected among the progeny of such plants by observing the disruption of the Glu-l-Gpi-l-Gli-1 linkage on both the alien chromosome as well as along wheat chromosomes IB and ID. A frequency of 8·0 per cent recombination between the Gpi-U1 and the Gli-U1 loci was estimated when chromosomes HJ and IB were simultaneously monosomic, whereas the rate of recombination was only 4·6 per cent when IB was present as a disome. Some double homoeologous recombinants between the three loci Glu-1, Gpi-1 and Gli-1 were also isolated. Control populations, where homoeologous pairing was suppressed by the presence of Phi, did not produce any allosyndetic recombinants between Gpi-1 and Gli-1. © 1987, The Genetical Society of Great Britain.