Molecular Mapping Of The Dwarfing Gene Rht-dp In Dwarfing Polish Wheat From Xinjiang With SSR And AFLP Markers

Dwarfing polish wheat (DPW) is a dwarfing accession of Triticum polonicum L. from Xinjiang of China. The dwarfing gene of DPW was recessive and tentatively named Rht-dp. In this study, dwarfing polish wheat and tall polish wheat were used as the hybridized parents to construct the hybrid F2population, SSR and AFLP technology were applied for mapping the dwarfing gene, and BF-MR1of the specific primer of Rht-B1b was used for homology detection of Rht-dp.1. In order to map the height-reducing gene Rht-dp, a total of187SSR primer pairs covering A and B wheat chromosomes and184pairs AFLP primers were used for polymorphism analysis of AS302and AS304. Among these primers,65(34.76%) pairs and67(36.41%) pairs showed polymorphism between the parents, respectively. By Bulk Segregant Analysis (BSA) of dwarfing and tall pools, eight pairs of SSR primers located on chromosome arm4BS, WMC511、Xgwm495、Xgwm113、 Xgpw7026、Xgwm192、 Xgpw7521、Xgpw3017and Xgpw1108, and two pairs of AFLP primers, M8E5and M4E3, were polymorphic. The124individuals of F2generation were then amplified with the ten markers, the results showed that all of the ten markers were linked to the Rht-dp gene. Further molecular mapping showed that Rht-dp was linked with the SSR markers and AFLP markers in the order of Xgpw7521-Xgpw7026-Xgpw1108-Xgwml92-Xgwm495-WMC511-M8E5-Rht-dp-Xgpw3017-M4E3-Xgwm113with genetic distances of17.7cM.5.3cM、5.1cM、2.2cM、8.4cM、2.0cM、3.5cM、0.5cM、4.5cM and0.3cM using the mapping program Mapmaker3.0. The results in this study will be useful for marker-assisted selection of alternative height-reducing genes, and to better map and clone Rht-dp gene.2. Using BF-MR1of the specific primer of Rht-B1b to amplify Rht-dp gene and Rht-B1b gene, and then cloning and sequencing the resulting fragments, the result of sequence alignment showed that Rht-dp and Rht-B1b are exactly the same in this region, and Rht-dp may be a candidate gene at Rht-B1locus.