小麦聚合杂交早代Dx5优质基因的分子标记选择

将抗条锈基因（Yrx）、抗白粉病基因（Pm21）聚合，转入宁夏高产、优质（2°、17＋18、5＋10）小麦品种中，利用分子标记检测出多抗基因聚合体单株，以多抗聚合体单株为材料进行Dx5基因的分子标记选择。结果表明，Dx5基因的特异引物能扩增出片断为450bp的条带，生化标记证明凡是能扩增出450bp片段的单株均含有5＋10亚基条带，分子标记与生化标记结果一致，说明利用Dx5基因的特异分子标记选择5＋10优质亚基是可靠的、可行的。从多抗基因聚合体F3中选到3株具有Dx5基因的材料。Dx5基因的分子标记技术与SDS—PAGE图谱技术各有所长，两者结合应用结果更好。

Selecting of Early Generation to Dx5 Gene of Pyramiding Hybrid Wheat by Molecular Markers

Pyramiding the stripe rust resistance gene （Yrx） and powdery mildew resistance gene （Pm21） were transformed to high yield and high quality （Containing 2°, 17＋ 18,5 ＋ 10 subunits） of Ningxia wheat varieties,we detected pyramiding resistance genes of single plant by molecular marker to select DX5 gene. The results indicated that primers of gene Dx5 can amplify fragment of 450 bp,it was showed that any single plant amplified fragment of 450 bp all containing 5＋ 10 subunit by biochemical marker evidence,this is consistent with the results of biochemical marker analysis,it also indicates it is possible and dependable to select high quality 5＋ 10 subunit by gene Dx5 molecular marker,three plants containing DX5 gene have been chosen from pyramiding resistance genes of F3,there are different advantages between the technique of gene Dx5 molecular marker and SDS-PAGE mapping technique,it is better effect to put both technique together to use for research.