Triticum aestivum/Dasypyrum villosum translocation line Assembly. Triticum aestivum/Dasypyrum villosum translocation line

Genomics studies in wild species of wheat have been limited due to the lack of references; however, new technologies and bioinformatics tools have much potential to promote genomic research. The wheat-Haynaldia villosa translocation line T6VS/6AL has been widely used as a backbone parent of wheat breeding in China. Therefore, revealing the genome structure of translocation chromosome 6VS/6AL will clarify how this chromosome formed and will help to determine how it affects agronomic traits. In this study, chromosome flow sorting, NGS sequencing and Chicago long-range linkage assembly were innovatively used to produce the assembled sequences of 6VS/6AL, and gene prediction and genome structure characterization at the molecular level were effectively performed. The analysis discovered that the short arm of 6VS/6AL was actually composed of a large distal segment of 6VS, a small proximal segment of 6AS and the centromere of 6A, while the collinear region in 6VS corresponding to 230-260 Mb of 6AS-Ta was deleted when the recombination between 6VS and 6AS occurred. Moreover, a fine physical bin map of 6VS was constructed by the high-throughput developed 6VS-specific InDel markers and a series of newly identified small fragment translocation lines involving 6VS. This study will provide essential information for mining of new alien genes carried by the 6VS/6AL translocation chromosome.