Professor Institute of Genetics and Developmental Biology, Chinese Academy of Sciences Beijing, Beijing, China (People's Republic)
To meet the world summit on food security, 50% more food is required by 2050, putting enormous pressure on increasing the yield per unit area. Cultivated rice is now the staple food feeding more than half of the world’s population, which are all diploid. Polyploidization of rice has long been desired because of its advantages in genome buffering, vigorousness, and environmental robustness. However, a workable route remains elusive. Here, we described a practical strategy, namely de novo domestication of wild allotetraploid rice. By screening allotetraploid wild rice inventory, we identified one genotype of O. alta (CCDD), Polyploid Rice 1 (PPR1), and established two important resources for its de novo domestication: 1) an efficient tissue culture, transformation, and genome editing system, and 2) a high-quality genome assembly discriminated into two subgenomes of 12 chromosomes apiece. With these resources, we showed that six agronomically important traits could be rapidly improved by editing O. alta homologs of the genes controlling these traits in diploid rice. The strategy of the de novo domestication of wild allotetraploid rice demonstrated a clear path by combining the advantages of (1) polyploidy, (2) functional genomics knowledge of cultivated crops, (3) desirable attributes of wild species, and (4) rapid genetic modification(s) through genome editing for creating novel crops to strengthen world food security in the future.