''Dioscorea japonica'', known as East Asian mountain yam, yamaimo, or Japanese mountain yam, is a type of yam (''

Dioscorea ''Dioscorea'' is a genus of over 600 species of flowering plants in the family Dioscoreaceae, native throughout the tropical and warm temperate regions of the world. The vast majority of the species are tropical, with only a few species extendin ...

'') native to

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

(including

Ryukyu The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Geography of Taiwan, Taiwan: the Ryukyu Islands are divided into the Satsunan Islands (Ōsumi Islands, Ōsumi, Tokara Islands, Tokara and A ...

and

Bonin Islands The Bonin Islands, also known as the , is a list of islands of Japan, Japanese archipelago of over 30 subtropical and Island#Tropical islands, tropical islands located around SSE of Tokyo and northwest of Guam. The group as a whole has a total ...

Korea Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically Division of Korea, divided at or near the 38th parallel north, 3 ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...

, and

Assam Assam (, , ) is a state in Northeast India, northeastern India, south of the eastern Himalayas along the Brahmaputra Valley, Brahmaputra and Barak River valleys. Assam covers an area of . It is the second largest state in Northeast India, nor ...

.Kew World Checklist of Selected Plant Families
/ref> ''Dioscorea japonica'' is used for food. ''Jinenjo'', also called the wild yam, is a related variety of Japanese yam that is used as an ingredient in ''

soba Soba ( or , "buckwheat") are Japanese noodles made primarily from buckwheat flour, with a small amount of wheat flour mixed in. It has an ashen brown color, and a slightly grainy texture. The noodles are served either chilled with a dipping sau ...

'' noodles. Mugitoro gohan 1

Names

In Japanese, it is known as . is another kind of ''Dioscorea japonica'', which is native to fields and mountains in Japan. In Chinese, ''Dioscorea japonica'' is known as ''yě shānyào'' () which translates to English as "wild

Chinese yam ''Dioscorea polystachya'' or Chinese yam ( zh, s=山药, t=山藥), also called cinnamon-vine, is a species of flowering plant in the yam family. It is sometimes called Chinese potato or by its Korean name ''ma''. It is also called huaishan in M ...

" or simply "wild yam". Another name is ''Rìběn shǔyù'' (; literally "Japanese yam"). In Korean, it is known as ''cham ma'' (), as well as ''dang ma'' ().

Chemistry

''Dioscorea japonica'' contains the

antimutagenic Antimutagens are the agents that interfere with the mutagenicity of a substance. The interference can be in the form of prevention of the transformation of a promutagenic compound into actual active mutagen, inactivation, or otherwise the preventio ...

compounds eudesmol and

paeonol Paeonol is a phenolic compound found in peonies such as ''Paeonia suffruticosa'' (moutan cortex), in '' Arisaema erubescens'', and in ''Dioscorea japonica''. It is a chemical compound found in some traditional Chinese medicines. Biological eff ...

Varieties

Several formal botanical varieties have been proposed. Four are accepted: # ''Dioscorea japonica'' var. ''japonica'' - Japan (Ryukyu, Bonin), Korea, Taiwan, China (Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Zhejiang) # ''Dioscorea japonica'' var. ''nagarum'' Prain & Burkill - India (Assam) # ''Dioscorea japonica'' var. ''oldhamii'' R.Knuth - China (Guangdong, Guangxi), Taiwan # ''Dioscorea japonica'' var. ''pilifera'' C.T.Ting & M.C.Chang - China (Anhui, Fujian, Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Zhejiang)

Uses

In Japanese cuisine, both the Japanese yam and the introduced

are used interchangeably in dishes and recipes. The yam's aerial

tubercles In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projection, b ...

, or

bulbils A bulbil (also referred to as a bulbel, bulblet, and/or pup) is a small, young plant that is reproduced vegetatively from axillary buds on the parent plant's stem or in place of a flower on an inflorescence. These young plants are clones of the ...

, called ''mukago'', are also eaten. They are often cooked and served with white rice.

References

{{Authority control japonica East Asian vegetables Flora of Assam (region) Flora of China Flora of Eastern Asia Flora of Korea Flora of Taiwan Plants described in 1784 Root vegetables

Names

Chemistry

Varieties

Uses

See also

References