Linkage relations of Gli-D1, Rg2, and Lr21 on the short arm of chromosome 1D in wheat

Abstract

Homozygous recombinant substitution lines, derived from a cross of Triticum aestivum 'Chinese Spring' with a disomic substitution line of Triticum tauschii chromosome 1D in 'Chinese Spring', were used to investigate the linkage relationships among the loci Glu-D1, encoding high molecular weight glutenin storage proteins, Gli-D1, encoding gliadin storage proteins, Rg2, controlling glume color, and Lr21, conferring leaf-rust resistance. Gli-D1, on chromosome arm 1DS, is tightly linked to Rg2 and Lr21 (1.4 and 5.6% recombination, respectively). The order of the loci is Gli-D1–Rg2–Lr21. Glu-D1, on chromosome arm 1DL, segregates independently (P = 0.43) of Gli-D1, Rg2, and Lr21. The position of Glu-D1, Gli-D1, Rg2, and Lr21 in the genetic linkage map of chromosome 1D agrees with the position of storage protein, glume color, and rust-resistance loci on chromosomes 1A and 1B.Key words: leaf-rust resistance, seed storage protein, glutenin, gliadin, glume color, Triticum aestivum, Triticum tauschii.