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bioRxiv · 10.1101/2021.08.09.455628

Genome sequences of Aegilops species of section Sitopsis reveal phylogenetic relationships and provide resources for wheat improvement

Avni, R.·Lux, T.·Minz-Dub, A.·Millet, E.·Sela, H.·Distelfeld, A.·Deek, J.·Yu, G.·Steuernagel, B.·Pozniak, C.·Ens, J.·Gundlach, H.·Mayer, K. F. X.·Himmelbach, A.·Stein, N.·Mascher, M.·Spannagl, M.·Wulff, B. B.·Sharon, A.
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Abstract

Aegilops is a close relative of wheat (Triticum spp.), and Aegilops species in the section Sitopsis represent a rich reservoir of genetic diversity for improvement of wheat. To understand their diversity and advance their utilization, we produced whole-genome assemblies of Ae. longissima and Ae. speltoides. Whole-genome comparative analysis, along with the recently sequenced Ae. sharonensis genome, showed that the Ae. longissima and Ae. sharonensis genomes are highly similar and most closely related to the wheat D subgenome. By contrast, the Ae. speltoides genome is more closely related to the B subgenome. Haplotype block analysis supported the idea that Ae. speltoides is the closest ancestor of the wheat B subgenome and highlighted variable and similar genomic regions between the three Aegilops species and wheat. Genome-wide analysis of nucleotide-binding site leucine-rich repeat (NLR) genes revealed species-specific and lineage-specific NLR genes and variants, demonstrating the potential of Aegilops genomes for wheat improvement. TeaserGenome sequences of Aegilops species provides a key for efficient exploitation of this rich genetic resource in wheat improvement.

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Avni, R., Lux, T., Minz-Dub, A., Millet, E., Sela, H., Distelfeld, A., Deek, J., Yu, G., Steuernagel, B., Pozniak, C., Ens, J., Gundlach, H., Mayer, K. F. X., Himmelbach, A., Stein, N., Mascher, M., Spannagl, M., Wulff, B. B., Sharon, A.. 2021-08-09. Genome sequences of Aegilops species of section Sitopsis reveal phylogenetic relationships and provide resources for wheat improvement. https://doi.org/10.1101/2021.08.09.455628

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