physical mapping resources for large plant genomes radiation hybrids for wheat d-genome progenitor aegilops tauschii：物理资源映射的大型植物基因组辐射杂种小麦d基因组祖粗山羊草.pdf

Kumar et al. BMC Genomics 2012, 13:597 /1471-2164/13/597 RESEARCH ARTICLE Open Access Physical mapping resources for large plant genomes: radiation hybrids for wheat D-genome progenitor Aegilops tauschii 1 1 1 1 1 Ajay Kumar , Kristin Simons , Muhammad J Iqbal , Monika Michalak de Jiménez , Filippo M Bassi , 1 2,6 3 3 4 3 2 Farhad Ghavami , Omar Al-Azzam , Thomas Drader , Yi Wang , Ming-Cheng Luo , Yong Q Gu , Anne Denton , Gerard R Lazo3 5 4 1 1* , Steven S Xu , Jan Dvorak , Penny MA Kianian and Shahryar F Kianian Abstract Background: Development of a high quality reference sequence is a daunting task in crops like wheat with large (~17Gb), highly repetitive (80%) and polyploid genome. To achieve complete sequence assembly of such genomes, development of a high quality physical map is a necessary first step. However, due to the lack of recombination in certain regions of the chromosomes, genetic mapping, which uses recombination frequency to map marker loci, alone is not sufficient to develop high quality marker scaffolds for a sequence ready physical map. Radiation hybrid (RH) mapping, which uses radiation induced chromosomal breaks, has proven to be a successful approach for developing marker scaffolds for sequence assembly in animal systems. Here, the development and characterization of a RH panel for the mapping of D-genome of wheat progenitor Aegilops tauschii is reported. Results: Radiation dosages of 350 and 450 Gy were optimized for seed irradiation of a synthe