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bioRxiv · 10.1101/2022.03.30.486474

Insights into the domestication of avocado and potential genetic contributors to heterodichogamy

Solares, E. A.·Morales-Cruz, A.·Figueroa Balderas, R.·Focht, E.·Ashworth, V. E. T. M.·Wyant, S. R.·Minio, A.·Cantu, D.·Arpaia, M. L.·Gaut, B. S.
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Abstract

O_LIThe domestication history of avocado (Persea americana) remains unclear, in part due to a lack of suitable genomic tools. C_LIO_LIWe created a reference genome from the Gwen varietal, which is closely related to the economically dominant Hass varietal. We also compiled a database of 34 resequenced accessions that represented the three botanical races of P. americana. C_LIO_LIOur genome assembly had an N50 of 3.37 megabases, a BUSCO score of 91% and was scaffolded with a genetic map, producing 12 pseudo-chromosomes with 49,450 genes. We used the Gwen genome as a reference to investigate the population genomics of avocado. Our analyses were consistent with three separate domestication events; we estimated that the Mexican race diverged from the Lowland (formerly known as West Indian) and Guatemalan races >1 million years ago. We also identified putative targets of selective sweeps in domestication events; within the Guatemalan race, putative candidate genes were enriched for fruit development and ripening. We also investigated divergence between heterodichogamous flowering types. C_LIO_LIWith the help of a new reference genome, we inferred the domestication history of avocado and identified genes that may contribute to heterodichogamy, including genes with functions in pollination and floral development. C_LI

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Solares, E. A., Morales-Cruz, A., Figueroa Balderas, R., Focht, E., Ashworth, V. E. T. M., Wyant, S. R., Minio, A., Cantu, D., Arpaia, M. L., Gaut, B. S.. 2022-04-01. Insights into the domestication of avocado and potential genetic contributors to heterodichogamy. https://doi.org/10.1101/2022.03.30.486474

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