High-resolution Introgressive Region Map Reveals Spatiotemporal Genome Evolution in Asian Rice Domestication

Abstract

3 3 3 4Domestication is anthropogenic evolution that fulfills mankind's critical food 3 5 demand. As such, elucidating the molecular mechanisms behind this process 3 6 promotes the development of future new crops. With the aim of understanding the 3 7 2 whole domestication process of Asian rice and by employing the Oryza sativa 3 8 subspecies (indica and japonica) as an Asian rice domestication model, we 3 9 scrutinized genomic introgressions between them as traces of domestication. Here 4 0 we show the genome-wide introgressive region (IR) map of Asian rice, by utilizing 4 1 4,587 accession genotypes with a stable outgroup species, particularly at the finest 4 2 resolution through a machine learning-aided method. The IR map revealed that 4 3 14.2% of the rice genome consists of IRs, including both wide IRs (recent) and 4 4 narrow IRs (ancient). This introgressive landscape with their time calibration 4 5 indicates that introgression events happened in multiple genomic regions over 4 6 multiple periods. From the correspondence between our wide IRs and so-called 4 7