The First Domesticated 'Cheongju Sorori Rice' Excavated in Korea

Area of Science:

• Archaeobotany
• Paleogenetics
• Agricultural Science

Background:

• Archaeological excavations at the Sorori paleolithic site in Cheongju, Republic of Korea, yielded ancient rice and Quasi-rice.
• The peat layer containing the rice was dated to over 15,000 years old, making it significant for early human history.

Purpose of the Study:

• To analyze the morphological characteristics, crushing properties, and DNA polymorphism of ancient rice grains from the Sorori site.
• To compare these findings with wild, weed, and modern rice varieties to understand genetic relationships.
• To investigate the origin of rice domestication in Korea.

Main Methods:

• Excavation and dating of rice samples.
• Morphological analysis (length, width) of rice grains.
• DNA band pattern analysis for genetic polymorphism.
• Comparative analysis with extant rice types.

Main Results:

• 127 rice seeds were excavated, including 18 ancient rice and 109 Quasi-rice.
• Short-grained ancient rice (average 7.19 mm length, 3.08 mm width) were identified.
• Quasi-rice exhibited distinct morphological differences from rice.
• DNA analysis indicated genetic similarities and differences with wild, weed, and modern rice.

Conclusions:

• The morphological, ecological, and physiological variations suggest the Sorori rice grains are crucial for understanding rice domestication in Korea.
• DNA sequencing results provide vital clues for estimating the origin of early rice domestication.