Usage of wild Oryza germplasms for breeding in pan-genomics era

One approach to sustainable agricultural production in a changing global environment is the effective utilization of unutilized germplasms. Among these, crop wild relatives (CWRs) represent valuable germplasms that retain the diversity lost during domestication. The genus Oryza has two cultivated species and 22 wild species. One of the cultivated species, Oryza sativa, produces the rice that is the staple food for half of the world's population. We are responsible for the maintenance and distribution of wild Oryza genetic resources held by Japan's National Institute of Genetics (NIG). The NIG has collected the genome sequences of numerous wild Oryza accessions, aiming at understanding and promoting the utilization of Oryza germplasm for both basic and applied sciences, such as breeding. The genome information of many wild Oryza germplasms deciphered by multiple groups is publicly available in databases, allowing for pangenome analysis. This review mainly introduces the wild Oryza genetic resources held by the NIG, discusses the genome diversity revealed through genome sequencing, presents new attempts to utilize wild Oryza germplasm as novel resources enabled by genome sequencing, and discusses the challenges in further effectively utilizing wild Oryza germplasm in breeding.