Genome analyses reveal the hybrid origin of the staple food crop white Guinea yam

Sugihara, Y.; Darkwa, K.; Yaegashi, H.; Natsume, S.; Shimizu, M.; Abe, A.; Hirabuchi, A.; Ito, K.; Oikawa, K.; Tamiru-Oli, M.; Ohta, A.; Matsumoto, R.; Paterne, A.; De Koeyer, D.; Pachakkil, B.; Yamanaka, S.; Muranaka, S.; Takagi, H.; White, B.; Asiedu, R.; Innan, H.; Asfaw, A.; Adebola, P.; Terauchi, R.

doi:10.1101/2020.07.14.202564

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bioRxiv · 10.1101/2020.07.14.202564

Genome analyses reveal the hybrid origin of the staple food crop white Guinea yam

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Abstract

White Guinea yam (Dioscorea rotundata) is an important staple tuber crop of West Africa. However, its origin remains unclear. In this study, we re-sequenced 336 accessions of white Guinea yam and compared them with the sequences of the wild Dioscorea species using an improved reference genome sequence of D. rotundata. Our results suggest a hybrid origin of white Guinea yam from crosses between the rainforest wild species D. praehensilis and the savannah-adapted D. abyssinica. We identified a higher genomic contribution from D. abyssinica in the sex chromosome of Guinea yam and an extensive introgression around the SWEETIE gene. Our findings point to a complex domestication scenario for Guinea yam and highlight the importance of wild species as gene donors for improvement of this crop through molecular breeding.

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Sugihara, Y., Darkwa, K., Yaegashi, H., Natsume, S., Shimizu, M., Abe, A., Hirabuchi, A., Ito, K., Oikawa, K., Tamiru-Oli, M., Ohta, A., Matsumoto, R., Paterne, A., De Koeyer, D., Pachakkil, B., Yamanaka, S., Muranaka, S., Takagi, H., White, B., Asiedu, R., Innan, H., Asfaw, A., Adebola, P., Terauchi, R.. 2020-07-15. Genome analyses reveal the hybrid origin of the staple food crop white Guinea yam. https://doi.org/10.1101/2020.07.14.202564

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