赤豆Vigna angularis (Willd.) Ohwi et Ohashi

别名：adzuki bean;赤小豆;红小豆;红豆;小豆;

科名：豆科 Leguminosae

属名：豇豆属 Vigna

《中国植物志》第41卷287页
  12.赤豆（唐本草）小豆（通称）红豆（广州），红小豆〔东北）
  Vigna angularis (Willd.) Ohwi et Ohashi in Journ. Jap. Bot. 44: 29. 1969; Verdc. in Kew Bull. 24:557. 1970.——Dolichos angularis Willd. Sp. Pl. 3: 1051. 1800.——Phaseolus angularis W. F. Wight in U. S. Dept. Agr. Bur. Pl. Ind. Bull. 137:17. 1909; How in Acta Phytotax. Sin. 3:78. 1954;中国主要植物图说·豆科717. 图696. 1955;海南植物志2: 324. 1965; 东北草本植物志5: 169. 1976.——Azukia angularis (Willd.) Ohwi, Fl. Jap. 691. 1953. et in Bull. Nat. Sci. Mus. Tokyo 33:77. 1953.
  一年生、直立或缠绕草本。高30-90厘米，植株被疏长毛。羽状复叶具3小叶；托叶盾状着生，箭头形，长0.9-1.7厘米；小叶卵形至菱状卵形，长5-10厘米，宽5-8厘米，先端宽三角形或近圆形，侧生的偏斜，全缘或浅三裂，两面均稍被疏长毛。花黄色，约5或6朵生于短的总花梗顶端；花梗极短；小苞片披针形，长6-8毫米；花萼钟状，长3-4毫米；花冠长约9毫米，旗瓣扁圆形或近肾形，常稍歪斜，顶端凹，翼瓣比龙骨瓣宽，具短瓣柄及耳，龙骨瓣顶端弯曲近半圈，其中一片的中下部有一角状凸起，基部有瓣柄；子房线形，花柱弯曲，近先端有毛。荚果圆柱状，长5-8厘米，宽5-6毫米，平展或下弯，无毛；种子通常暗红色或其他颜色，长圆形，长5-6毫米，宽4-5毫米，两头截平或近浑圆，种脐不凹陷。花期夏季，果期9-10月。
  我国南北均有栽培。美洲及非洲的刚果、乌干达亦有引种。
  种子供食用，煮粥、制豆沙均可。干豆含蛋白质21-23%，脂肪0.3%，碳水化合物65%。（据J. W. Purseglove, Trop, Crop Dicot. 289-290. 1977.）▽红色赤豆入药治水肿脚气、泻痢、痈肿，并为缓和的清热解毒药及利尿药；浸水后捣烂外敷，治各种肿毒。
  据记载（Hara & Williams, Enum. Fl. Pl. Nepal 2:105. 1979）我国东北亦栽培有本种的一个变种日本赤豆 var. nipponensis (Ohwi) Ohwi et Ohashi，特征为茎蔓生，稍纤细，顶生小叶狭卵形，花序常有毛，荚果带黑色，长4-5厘米，果瓣质地稍薄。惟作者未见标本，且1976年出版的《东北草本植物志》亦未收载，故暂附记于此。

《Flora of China》 Vol. 10 (2010)
Vigna angularis  (Willdenow) Ohwi & H. Ohashi J. Jap. Bot. 44: 29. 1969.
赤豆   chi dou
Dolichos angularis Willdenow, Sp. Pl. 3: 1051. 1800; Azukia angularis (Willdenow) Ohwi; Phaseolus angularis (Willdenow) W. Wight; P. nipponensis Ohwi; Vigna angularis var. nipponensis (Ohwi) Ohwi & H. Ohashi.
Annual herbs, erect or twining, 30-90 cm tall. Stems angular, sparsely pilose. Stipules peltate, lanceolate, ca. 8 mm, point of attachment elongated; leaflets ovate or rhomboid-ovate, 5-10 × 5-8 cm, sparsely pilose on both surfaces, apex broadly triangular or subrounded, lateral leaflets oblique, entire or shal-lowly 3-lobed. Racemes axillary, 5- or 6-flowered, pedunculate. Calyx campanulate, 3-4 mm. Corolla yellow, ca. 15 mm; stan-dard oblate or subreniform, apex emarginate; wings broader than keel, shortly clawed and auriculate; keel apex incurved for nearly a half circle, base clawed. Ovary linear; style curved. Legumes terete, 5-8 × 0.5-0.6 cm, glabrous or almost so. Seeds dull red or with various other colors, oblong, 5-6 × 4-5 mm, truncate or subrounded at both ends; hilum not impressed. Fl. Jun-Jul, fr. Sep-Oct.
Widely cultivated and also wild in China [native to Asia; intro-duced in America, Africa, and elsewhere].
This species is edible and is used medicinally.This species is edible and is used medicinally.