a1 Plant Breeding Institute, Maris Lane, Trumpington, Cambridge, CB2 2LQ, U.K.
Over one hundred backcross-one progeny were analysed by two dimensional electrophoresis to locate the genes on the short arm of chromosome 1D which code for, or control, the D group of LMW glutenin subunits. Recombination between these genes and Glu-D 1, encoding HMW glutenin subunits, was frequent but none could be detected between the D subunit genes and Gli-D1, coding for ω-gliadins, γ-gliadins and the B group of LMW glutenin subunits. These results are in contrast to those for chromosome 1 B because apparently homoeologous D subunit genes occur at a different position, being equidistant between Glu-B 1 (homoeologous to Glu-D 1) and Gli-B 1 (homoeologous to Gli-D 1). A range of 18 genetically-diverse wheat varieties, each containing one of two allelic groups of 1 D-encoded D subunits, were also analysed by two-dimensional electrophoresis. Consistent with the genetic analysis above, unbreakable linkages were found between these alleles and alleles of Gli-D 1. The results are discussed in relation to the evolution of the distribution of prolamin genes in the wheat genome.
(Received January 30 1986)