Japonica rice

Japonica rice (Oryza sativa subsp. japonica), sometimes called sinica rice, is one of the two major domestic types of Asian rice varieties. Japonica rice is extensively cultivated and consumed in East Asia, whereas in most other regions indica rice is the dominant type of rice. Japonica rice originated from Central China, where it was first domesticated along the Yangtze River basin approximately 9,500 to 6,000 years ago.^[1][2][3]

Grains of japonica rice

Japonica rice field in Japan

Classification

The subspecies japonica can be classified into three subgroups, 'temperate japonica', 'tropical japonica' (obsolete designations: 'javanica'; Oryza sativa subsp. javanica [ja]),^[4] and 'aromatic'.^[5] Temperate japonica is cultivated in East Asia (China, Japan, Korea, Vietnam, and Taiwan), while tropical japonica is in Indonesia, Madagascar, and also the Americas where it was brought to with slave trade.^[6]

• 
  Glutinous japonica rice
• 
  Aromatic japonica rice
• 
  Black japonica rice
• 
  Green japonica rice

Characteristics

Japonica rice grains are rounder, thicker, and harder, compared to longer, thinner, and fluffier indica rice grains. Japonica rice is also stickier due to the higher content of amylopectin, whereas indica rice starch consists of less amylopectin and more amylose.^[7] Japonica rice plants are shorter than indica rice plants.^{[citation needed]}

Genetics

Temperate japonica has a large amount of waxy protein and a low amount of the non-waxy type.^{[8]: 12–13} Non-waxy rice proteins are produced by four alleles, each producing one of four protein subtypes.^{[8]: 12–13} Temperate japonica is the only source of Type III, shares Type IV with only tropical japonica ("javanica"), and lacks Type I and Type II.^{[8]: 12–13}

Cultivars

• Arborio rice
• Bhutanese red rice
• Bomba rice
• Calrose rice
• Carnaroli
• Koshihikari
• Vialone Nano
• Yamada Nishiki

See also

• Japanese rice

References

1. Hirst, K. Kris. "The Origins and History of Rice in China, India/Pakistan and Africa". ThoughtCo. Retrieved 2020-08-02.
2. Devitt, James (2011-05-02). "Rice's origins point to China, genome researchers conclude". Washington University in St. Louis. Retrieved 2020-08-02.
3. Gross, Briana L.; Zhao, Zhijun (2014-04-29). "Archaeological and genetic insights into the origins of domesticated rice". Proceedings of the National Academy of Sciences. 111 (17): 6190–6197. Bibcode:2014PNAS..111.6190G. doi:10.1073/pnas.1308942110. ISSN 0027-8424. PMC 4035933. PMID 24753573.
4. "javanica rice". International Rice Research Institute. Retrieved 27 December 2016.
5. Garris, Amanda J.; Tai, T. H.; Coburn, J.; Kresovich, S.; McCouch, S. (2004). "Genetic structure and diversity in Oryza sativa L." Genetics. 169 (3): 1631–1638. doi:10.1534/genetics.104.035642. PMC 1449546. PMID 15654106.
6. 松尾 弌之. (2009).“「アメリカ50州」の秘密 “ レッカ社 ISBN 4569673023
7. Kim, Jin-young (4 November 2016). "Endless Variations on Rice". Koreana. Korea Foundation. Retrieved 27 December 2016.
8. Rice Genetics : Proceedings of the Second International Rice Genetics Symposium 14-18 May 1990. Rice Genetics Collection. Vol. 2. Manila, Philippines: International Rice Research Institute. 1991.