Chromosome 1D in wheat (Triticum aestivum L.): Linkage map, quantitative traits, and effect of telosomes on recombination values.

摘要

A genetic linkage map of chromosome 1D in wheat was created using four sets of homozygous recombinant substitution lines (RSLs), derived from crosses of Triticum aestivum 'Chinese Spring' and Chinese Spring double-ditelosomic 1D with two disomic substitution lines of chromosome 1D of T. tauschii accessions RL5288 and RL5289 substituted into Chinese Spring. The location of the regions of the chromosome that control the quantitative traits dough-mixing time, protein concentration and bread loaf volume, and the potential bias in recombination when RSLs are derived from plants double-monotelotrisomic were investigated. The loci Glu-D1, encoding high-molecular-weight glutenin storage proteins Glu-D3, encoding low molecular weight glutenin storage proteins Gli-D1, encoding gliadin storage proteins Rg2, controlling glume color Lr21, conferring leaf rust resistance Sr33, conferring stem rust resistance and the centromere were incorporated into the map. Classification by chromosome constitution of RSLs derived from plants double-monotelotrisomic (those from crosses involving Chinese Spring double-ditelosomic 1D) showed that recombination values observed were significantly over-estimated in the double-ditelosomic-derived groups and under-estimated in the normal-chromosome-derived groups in comparison to recombination values observed in crosses involving only normal chromosomes. The discordant recombination values were explained by the amount of telosome paring and differences in the transmission of unrecombined chromosome arms for the two types of chromosomes. The gene order and consensus recombination distances for the RL5288 source of 1D were Glu-D1 - 16.5 - centromere - 29.6 - Sr33 - 6.6 - Gli-D1, and for the RL5289 source were Glu-D1 - 15.9 - centromere - 39.2 - Glu-D3 - 4.0 - Gli-D1 - 2.5 - Rg2 - 3.6 - Lr21. Chromosome 1D from T. tauschii contributed to improved dough-mixing and bread loaf volume. These effects were associated with Glu-D3, Gli-D1, Rg2, and Lr21 but not with Glu-D1. The RSLs were used to show that the improved quality was most strongly associated with Gli-D1.