Submitted to: Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2006
Publication Date: 6/1/2006
Citation: Kalavacharla, V., Hossain, K., Gu, Y.Q., Riera, L.O., Isabel, V.M., Bhamidimarri, S., Gonzalez-Hernandez, J., Maan, S., Kianian, S. 2006. High-resolution radiation hybrid map of wheat chromosome 1d. Genetics. 173:1-11. Interpretive Summary: Cloning and manipulating genes that control important traits for crop improvement remain a great chanllenge in wheat because of its large and complex genome. A high resolution physical map will not only greatly enhance our understanding of the genome structure and organization, but also provide a valuble resource for map-based cloning of trait genes for crop improvement. In this study, Radiation Hybrid mapping technology is employed to develop a high resolution map for wheat chromosome 1D. This is the highest resolution that has been obtained by plant RH mapping and serves as a first step for the development of radiation hybrid resources in wheat.
Technical Abstract: Physical mapping methods that do not rely on meiotic recombination are necessary for complex, polyploid genomes like wheat. This is due to uneven distribution of recombination and significant variation in genetic to physical distance correlations. It has been suggested that genes required for survival of the species are located in such regions of low recombination and ~30% of wheat genes are located in these regions. One such method of physical mapping that has proved valuable in a number of non-plant and plant systems is radiation hybrid (RH) mapping. This work presents for the first time, a high-resolution radiation hybrid map of wheat chromosome 1D (D-genome) in a tetraploid durum wheat (AB genome) background. The RH panel of 87 lines was used to map 378 molecular markers which detected 2,312 breaks. The total map distance ranged from ~3341 cR35,000 centi rays (cR) for the five major linkage groups to 11,773 cR35,000 for the comprehensive map, and yielded a resolution of ~200 Kb/break. To date this is the highest resolution that has been obtained by plant RH mapping, and serves as a first step for the development of RH resources in wheat.