or are the common names for a small sized variety of

Japanese citrus A number of citrus fruits are grown in or strongly associated with Japan. Many of these fruits are of Chinese origin, but have been modified or specially bred for cultivation in Japan. Japanese taxonomy Japan usually follows the botanical name ...

, whose rind is of a characteristic "golden" bright yellow color. The variety has been published as the species ''Citrus flaviculpus'' by

Chōzaburō Tanaka , often Romanized as Tyôzaburô Tanaka (November 3, 1885 in Osaka – June 28, 1976), was a Japanese botanist and mycologist. He established one of the two major taxonomic classification systems for citrus and related genera currently in use, an ...

in his 160-species scheme, but this is considered an effort of a " splitter", as opposed to Swingle's classification system which is generally preferred in the West. Alternate spellings (romanizations) include "Ougonkan" or "Ogon-kan". It has also been called "Golden orange" in Kanagawa Prefecture.

History

The variety has long been known in Kagoshima Prefecture as but, precise origins are unknown. According to one assertion, it has been known in Higashi-ichiki-chō ( ja) and its neighborhood (now Hioki, Kagoshima) since the Meiji Period. Anecdotally in this Hioki area, the variety is said to have been either introduced by the Jesuit Francisco de Xavier, or brought back from the

Korean Peninsula Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...

during Hideyoshi's invasions of Korea in the late 16th century. It has been suggested that the name "Ōgonkan" was dubbed by who introduced the variety to

Ehime Prefecture is a prefecture of Japan located on the island of Shikoku. Ehime Prefecture has a population of 1,342,011 (1 June 2019) and has a geographic area of 5,676 km2 (2,191 sq mi). Ehime Prefecture borders Kagawa Prefecture to the northeast, Tok ...

, but this too is poorly documented.

Fruit

The small fruit has a diameter of , weighing . The rind, which is bright yellow, can be peeled by hand but with difficulty. It has a distinct fragrance, and a considerably sweet flavour, with some balancing acidity. The fruit is harvested from February to April. Seedless (

self-incompatibility Self-incompatibility (SI) is a general name for several genetic mechanisms that prevent self-fertilization in sexually reproducing organisms, and thus encourage outcrossing and allogamy. It is contrasted with separation of sexes among individuals ...

) traits have been observed. Its fragrance is similar to the

Hyuganatsu Hyuganatsu (''Citrus tamurana'', Japanese: 日向夏) is a citrus fruit and plant grown in Japan. The name comes from Hyūga, the ancient name of Miyazaki Prefecture in Kyushu, where the citrus is said to have originated, while means summer. ...

, a larger citrus that is also bright yellow, but somewhat sweeter by comparison. Like the Hyuganatsu, the white pith (''albedo'') may be eaten. The rind's cold-pressed oil has been studied for fragrance factors, and was found to contain

limonene Limonene is a colorless liquid aliphatic hydrocarbon classified as a cyclic monoterpene, and is the major component in the oil of citrus fruit peels. The -isomer, occurring more commonly in nature as the fragrance of oranges, is a flavoring a ...

(roughly 80%), followed by the

monoterpene Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen func ...

Gamma-terpinene (10%), trans beta-

farnesene The term farnesene refers to a set of six closely related chemical compounds which all are sesquiterpenes. α-Farnesene and β-farnesene are isomers, differing by the location of one double bond. α-Farnesene is 3,7,11-trimethyl-1,3,6,10-dodec ...

, and

myrcene Myrcene, or β-myrcene, is a monoterpene. A colorless oil, it occurs widely in essential oils. It is produced mainly semi-synthetically from '' Myrcia'', from which it gets its name. It is an intermediate in the production of several fragrances. ...

, showing similarity to Hyuganatsu's peel profile, though with quantitative differences in concentrations.

Regional production

According to government ( MAFF) statistics for FY2010, crop yield of the Ōgonkan totaled 137.3 t ( metric tons) in all of Japan, with 108.2 t shipped to market, none of it classed as processed goods (i.e., juices, etc.) in the statistics.

Kanagawa Prefecture is a prefecture of Japan located in the Kantō region of Honshu. Kanagawa Prefecture is the second-most populous prefecture of Japan at 9,221,129 (1 April 2022) and third-densest at . Its geographic area of makes it fifth-smallest. Kanag ...

produced 93.4 t, representing 68% of the national total, followed by Shizuoka Prefecture with 25.0 t (18％),

with 13.9 t, and

Kōchi Prefecture is a prefecture of Japan located on the island of Shikoku. Kōchi Prefecture has a population of 757,914 (1 December 2011) and has a geographic area of 7,103 km2 (2,742 sq mi). Kōchi Prefecture borders Ehime Prefecture to the northwest and ...

with 5.0 t. Major cultivating areas listed are

Odawara is a city in Kanagawa Prefecture, Japan. , the city had an estimated population of 188,482 and a population density of 1,700 persons per km2. The total area of the city is . Geography Odawara lies in the Ashigara Plains, in the far western por ...

and Yugawara-cho (Kanagawa pref.),

Numazu, Shizuoka is a city located in eastern Shizuoka Prefecture, Japan. , the city had an estimated population of 189,486 in 91,986 households, and a population density of 1,014 persons per km2. The total area of the city is . Geography Numazu is at the nor ...

Uwajima 270px, Uwajma City Hall 270px, Aerial view of Uwajma city center 270px, Japan National Route 320 in Uwajma city center is a city located in Ehime Prefecture, Japan. , the city had an estimated population of 70,440 in 35429 households and a ...

, Seiyo,

Imabari 270px, Imabari City Hall 270px, Aerial view of Imabari city center is a city in Ehime Prefecture, Japan. It is the second largest city in Ehime Prefecture. , the city had an estimated population of 152,111 in 75947 households and a population ...

(Ehime pref.), and Kōnan, Kōchi. 都道府県別平成22年産 (Citrus production statistics by prefecture, FY 2010
Excel
/ref>

Hybrid crossing

The Ōgonkan was the pollinating parent for the hybrid cultivar developed by

, and was the seed parent of Shonan Gold developed by

.媛小春（Hime-Koharu 17067）
http://www.hinsyu.maff.go.jp/vips2/cmm/apCMM112.aspx?TOUROKU_NO=11469&LANGUAGE=Japanese 湘南ゴールド（Shonan Gold 11469）] (English page links provided, but without any substantive description)

Notes

References

* * **山本雅史, 久保達也, 冨永茂人, 「カンキツにおける自家および交雑不和合性」園芸学会雑誌 75巻5号(2006年) ;In Japanese with English abstracts * (w/English title and abstract
Agriknowledge
(with PDF link)
Agri-kanagawa (pdf)
*: = *, JGLOBAL I
200902281400290696(pdf)
*: =

External links

Registration kind database
( MAFF cultivar registration database. Available in English with limited information. {{DEFAULTSORT:Ogonkan Citrus Food plant cultivars Fruits originating in East Asia Japanese fruit