Breeding a hard, winter type durum wheat by the gene shuttling method

普通小麦（基因组，AABBDD）携带具有重要农学意义的基因，如决定烘焙品质的Glu-D1d基因（位于1D染色体上）、决定半矮秆性的Rht2基因（位于4D染色体上）和决定强冬季生长习性的vrn3基因（位于5D染色体上），这些基因在硬粒小麦（AABB）中没有发现。本研究旨在利用硬粒小麦的d基因组染色体替代系将这些基因转移到硬粒小麦上。(1) Glu-D1d基因的转移：将兰登的1D （1A）和1D （1B）代换系杂交给两个面包小麦品种Max和Stoa，这两个品种携带Glu-D1d等位基因，可获得最好的谷蛋白含量。在纯合子条件下，成功地选择了几个具有2n=28和Glu-D1d等位基因的F_2植株。收获自花授粉后的籽粒，并对其面粉特性进行测试。两个剂量的Glu-D1d等位基因对面粉的蛋白质含量没有影响，但与兰登面粉相比，其混合耐受性明显增强，面包的体积和质地也有所改善。(2)转移更多的Rht基因：将携带Rht1和Rht2两个半矮型基因的日本品种Norin 10杂交给兰登，在F_2代进行染色体数和株高选择。在纯合子条件下，获得了携带Rht1和vrn1基因的F_3系。在另一个试验中，将诺林10号与兰登的4D （4A）和4D （4B）代换系杂交，在F_2代中对染色体数和株高进行了选择。在硬膜背景下获得了几个接近2n=28的短秆植株，推测为Rht2纯合子。(3) vrn基因的转移：将兰登的5D （5B）代换系与两个日本冬小麦品种杂交，获得vrn1和vrn3基因兼备的硬粒品系，在F_2代进行染色体数目选择，在F_3代进行生长习性选择。获得了几株冬季生长习性强、染色体数接近2n=28的F_3植株，推测为两个vrn基因的纯合子。少

Common wheat (genome, AABBDD) carries agronomically important genes, such as Glu-D1d gene (on chromosome 1D) for high baking quality, Rht2 gene (on 4D) for semidwarfism, and vrn3 (on 5D) for strong winter growth habit, which are not found in durum wheat (AABB). The present investigation aimed to transfer those genes to durum wheat using the D-genome chromosome substitution lines of a durum wheat.(1) Transfer of the Glu-D1d gene : Langdon's 1D (1A) and 1D (1B) substitution lines were crossed to two bread wheat cultivars, Max and Stoa, which carry a Glu-D1d allele for the best glutenin fractions. Several F_2 plants having 2n=28 and Glu-D1d allele in the homozygous condition were successfully selected. Grains set by self-pollination were harvested and flour characteristics were tested. Two doses of the Glu-D1d allele did not change protein content of flour but its mixing tolerance clearly was increased, and loaf volume and texture were improved, comparing to the Langdon's flour.(2) Transf … More er of the Rht genes : Japanese cultivar, Norin 10, that carries two semidwarf genes, Rht1 and Rht2, was crossed to Langdon and in the F_2 generation selection was made on chromosome number and plant height. An F_3 line was obtained that carries the Rht1 and vrn1 genes both in homozygous condition. In another experiment, crosses were made between Norin 10 and Langdon's 4D (4A) and 4D (4B) substitution lines and in the F_2 generation selection was made on chromosome number and plant height. Several short culm plants having nearly 2n=28 were obtained, which are assumed to be the Rht2 homozygote in the durum background.(3) Transfer of the vrn genes : To produce a durum line having both the vrn1 and vrn3 genes, Langdon's 5D (5B) substitution line was crossed to two Japanese winter cultivars of common wheat, and selection was made on chromosome number in the F_2 generation, and on growth habit in the F_3 generation. Several F_3 plants having strong winter growth habit and nearly 2n=28 chromosomes were obtained, which are assumed to be the homozygote of both vrn genes. Less