Genomic data from Aegilops tauschii - The Progenitor of Wheat D Genome

A spontaneous hybridization of the wild diploid grass Aegilops tauschii (2n=14, DD) with cultivated tetraploid wheat Triticum turgidum (2n=4x=28, AABB) 8,000~10,000 years ago in the Fertile Crescent resulted in the bread wheat (Triticum aestivum; 2n=6x=42, AABBDD), one of the earliest cultivated crops in modern agriculture. We sequenced the 4.36-gigabase (Gb) genome of Ae. tauschii by generating ~90x genome coverage of short reads from a series of libraries with various insert sizes. The assembled scaffolds of high quality sequences represent 83.4% of the genome, in which 65.9% comprised of repetitive elements. Assisted with comprehensive RNA-Seq data, we identified 43,150 protein-coding genes, with 30,697 (71.1%) of them uniquely anchored to chromosomes based on an integrated density genetic map. A number of agriculturally relevant gene families, such as disease resistance, abiotic stress tolerance, and grain quality genes, were found to expand in Ae. tauschii. The draft genome of Ae. tauschii hence provides novel insights into its role in enabling environmental adaptation of common wheat and in defining the large and complicated genomes of wheat species.