Genome Research Concludes Rice Originiated in China



Rice fields courtesy of edie209 via flickr

 On 2 May 2011 New York University issued a press release to publicize the findings of researchers from its Center for Genomics and Systems Biology.  Scientists from this unit teamed with colleagues at the Washington University in St. Louis (Department of Biology), Stanford University (Department of Genetic) and Purdue University (Department of Agronomy) to conclude that rice originated in China.  Previous research suggested two points of origin - China and India. 

Oryza sativa (Asian rice) is very diverse with tens of thousands of varieties.  There are know major subspecies - japonica and indica, from which most rice varieties orginate.  In this most recent research published in the Proceedings National Academy of Sciences (PNAS), the NYU scientists and their colleagues reviewed previously published evolutionary genome databases that concluded that japonic and indica rice had separate origins. "Using more modern computer algorithms, however, the researchers concluded these two species have the same origin because they have a closer genetic relationship to each other than to any wild rice species found in either India or China."

Current archaelogical research provides evidence for rice being domesticated approximately 9,000 to 8,000 years ago in the Yangtze Valley of China and 4,000 years ago in the Ganges region of India.  NYU researchers and their colleagues used genome "molecular clocks" to conclude that the (domesticated) parent of japonica and indica rice originated close to 8,200 years ago.  Japonica and indica split apart from each other about 3,900 years ago.

From this genome molecular research, NYU biologist Michael Purugganan concludes that "rice was brought in from China to India by traders and migrant farmers ... then hybridized extensively with local wild rice."

For more see:

"Rice’s Origins Point to China, Genome Researchers Conclude," New York University, News and Information, NYU Today, 2 May 2011.

Molina, J., M. Sikora, N. Garud, J. M. Flowers, S. Rubinstein, A. Reynolds, P. Huang, S. Jackson, B. A. Schaal, C. D. Bustamante, A. R. Boyko, and M. D. Purugganan. "Molecular Evidence for a Single Evolutionary Origin of Domesticated Rice [Evolution]." Proceedings of the National Academy of Sciences (05-02, 2011)