Vigna angularis (Willd.) Ohwi & Ohashi
[Azuki bean] SEED
To Japanese version
- <The situation in Japan and information from the NIAS genebank>
- Azuki bean is an ancient and important crop in Japan. The written record
of azuki bean has appeared in "Kojiki" and "Nihonshoki"
(8th century) (Hoshikawa 1981). Various landraces have been developed.
Farmers usually grow this crop for their own use. The main commercial production
area is in Hokkaido district (the northernmost island in Japan). Japan
imported 79,978 MT of azuki bean in 1994. More than 90% was imported from
China (Zatsumame Yunyu Kikin Kyokai. 1995).
In Japan, azuki bean has been used for making "sekihan" (steamed
glutinous rice colored red by boiled azuki or sasage bean,V.unguiculata)
and/or "azuki-gayu" (rice porridge with azuki bean) for the traditional
ceremony and celebration. It is also cooked as "ann" (azuki bean
jam) and/or "shiruko" (sweet azuki soup with glutinous rice cake).
- Azuki is considered to have been domesticated in China, Korea or Japan
from its wild ancestral form, V.angularis var.nipponensis
(Ohwi) Ohwi & Ohashi. Recently, the natural distribution of V.angularis
var.nipponensis was proved to be wider than recognized before, ranging
from Japan, Korea, China to Himalaya (Tateishi 1984, also see p.39, Fig.4.1.
in Lumpkin and McClary 1994). Therefore, the area of domestication should
be reconsidered from these regions. This area is called the "Sino-Japanese
Region" according to plant geography classification.
- Azuki bean is an annual food legume belonging to the subgenus Ceratotropis
in the genus Vigna. The genus Vigna, together with the closely
related genus Phaseolus, forms a very complicated taxonomic group,
so called Phaseolus-Vigna complex. Verdcourt (1970) proposed a very
restricted concept of Phaseolus, limiting it exclusively to those
American species with a tightly coiled style and pollen grains lacking
course reticulation, hence, promoting significantly the concept of Vigna.
According to his proposal, azuki bean, mungbean and its relatives (which
is now recognized as the subgenus Ceratotropis) were transferred
to the genus Vigna from the genus Phaseolus. Marechal et
al. (1978) followed Verdcourt and presented a monograph on the Phaseolus-Vigna
complex. Their taxonomic system is generally accepted now. 2n=22.
- Azuki bean has been cultivated in China, Korea and Japan. Usually,
it shows an erect growth habit, however some azuki bean cultivated in Nepal
and Bhutan shows twining form. Flower color is pale yellow. Seed color
is diverse, ranging from red, white, black, gray seed mottled with black
("called kage azuki in Japan") to white seed mottled with red
("called anego azuki in Japan"). Germination is hypogeal.
- The dry seeds are boiled and used in various ways.
- Hoshikawa,K. 1981. Azuki (Azuki bean). in "Shokuyou Sakumotu"
(Food Crops). Yoken-do, Tokyo. (in Japanese) pp.460-470.
- Lumpkin,T.A. and McClary,D.C. 1994. Azuki Bean : Botany, Production
and Uses. CAB International.
- Marechal,R., J.M.Mascherpa and F.Stainer. 1978. Etude taxonomique d'un
groupe complexe d'speces des genres Phaseolus et Vigna (Papilionaceae)
sur la base de donnees morphologiques et polliniques, traitees par l'analyse
informatique. Boissiera 28.
- Tateishi,Y. 1984. Contributions to the Genus Vigna (Leguminosae) in
Taiwan I. Sci. Rep. Tohoku Univ. 4th ser. (Biology) 38: 335-350.
- Verdcourt,B. 1970. Studies in the Leguminosae - Papilionoideae for
the "Flora of Tropical East Africa" : IV. Kew Bulletin 24 : pp.558-560.
- Zatsumame Yunyu Kikin Kyokai. 1995. Yunyu Mamerui Zukan (A pictorial
book of imported food legumes) (in Japanese).