Chromosome-scale genome assembly of bread wheat's wild relative Triticum timopheevii

Grewal, S.; Yang, C.; Scholefield, D.; Ashling, S.; Ghosh, S.; Swarbreck, D.; Collins, J.; Yao, E.; Sen, T. Z.; Wilson, M.; Yant, L.; King, I. P.; King, J.

doi:10.1101/2024.01.16.575864

bioRxiv · 10.1101/2024.01.16.575864

Chromosome-scale genome assembly of bread wheat's wild relative Triticum timopheevii

Grewal, S.·Yang, C.·Scholefield, D.·Ashling, S.·Ghosh, S.·Swarbreck, D.·Collins, J.·Yao, E.·Sen, T. Z.·Wilson, M.·Yant, L.·King, I. P.·King, J.

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Abstract

Wheat (Triticum aestivum) is one of the most important food crops with an urgent need for increase in its production to feed the growing world. Triticum timopheevii (2n = 4x = 28) is an allotetraploid wheat wild relative species containing the At and G genomes that has been exploited in many pre-breeding programmes for wheat improvement. In this study, we report the generation of a chromosome-scale reference genome assembly of T. timopheevii accession PI 94760 based on PacBio HiFi reads and chromosome conformation capture (Hi-C). The assembly comprised a total size of 9.35 Gb, featuring a contig N50 of 42.4 Mb, and 166,325 predicted gene models. DNA methylation analysis showed that the G genome had on average more methylated bases than the At genome. The G genome was also more closely related to the S genome of Aegilops speltoides than to the B genome of hexaploid or tetraploid wheat. In summary, the T. timopheevii genome assembly provides a valuable resource for genome-informed discovery of agronomically important genes for food security.

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Grewal, S., Yang, C., Scholefield, D., Ashling, S., Ghosh, S., Swarbreck, D., Collins, J., Yao, E., Sen, T. Z., Wilson, M., Yant, L., King, I. P., King, J.. 2024-01-17. Chromosome-scale genome assembly of bread wheat's wild relative Triticum timopheevii. https://doi.org/10.1101/2024.01.16.575864

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