Recently, Prof. LI Jiayang’s group from the CAS Institute of Genetics and Developmental Biology(IGDB) and his collaborators made a breakthrough toward creating novel crops throughde novodomestication of wild allotetraploid rice, which has launched a revolution for sustainable agriculture in creating future crops. This work entitled“A route tode novodomestication of wild allotetraploid rice” has been published online inCellon February 3, 2021.

To meet the world summit on food security, 50% more food is required by 2050, posing enormous pressure on increasing the yield per unit area. This challenge becomes even greater owing to rapid climate changes.Cultivated rice is now the staple food feeding more than half of the world’s population,which is all diploid.

De novo domestication of wild allotetraploid rice. (Image by IGDB)

Domestication of wild rice into cultivated crops spends thousands of years, accompanied with narrowed genetic diversity in the species populations. Compared with the cultivated diploid rice, South American species with a polyploid CCDD genome show a significantly higher biomass and greater resistance to biotic and abiotic stresses.

To create novel polyploid rice crop, Prof. LI has launched a strategy forde novodomestication of wild allotetraploid rice, which includes four steps: (1)selecting a wild allotetraploid rice material suitable forde novodomestication; (2) establishing an efficient transformation system for the targeted material; (3)assembling and analyzing a high-quality reference genome of the material; and (4) targeted editing of several domestication- and agronomy-related key genes to improve the important traits.

LI’s group and his collaborators then screened allotetraploid wild rice inventory and identified one genotype ofO. alta(CCDD), Polyploid Rice 1 (PPR1)to establish two important resources for itsde novodomestication: 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 they showed that six agronomically important traits could be rapidly improved by editingO. altahomologs of the genes that control these traits in diploid rice.

These results demonstrated that the proposed strategy is rational and practical, andde novodomesticated allotetraploid rice can be developed into a new staple cereal to strengthen world food security.

Contact:

Dr. LI Jiayang

Institute of Genetics and Developmental Biology (IGDB), CAS

Email: jyli@genetics.ac.cn