Fagopyrum

Miller

Gard. Dict. Abr. ed. 4, vol. 1. 1754.

Common names: Buckwheat sarrasin
Etymology: Latin fagus, beech, and Greek pyrus, wheat, alluding to resemblance of the achene to a beech-nut
Treatment appears in FNA Volume 5. Treatment on page 572. Mentioned on page 216, 217, 218, 479, 480.

Herbs, annual; taprooted. Stems erect or ascending, glabrous or puberulent. Leaves deciduous, cauline, alternate, petiolate (proximal leaves) or sessile (distal leaves); ocrea persistent or deciduous, chartaceous; petiole base articulated; blade cordate, triangular, hastate, or sagittate, margins entire to sinuate. Pedicels present. Inflorescences axillary, or terminal and axillary, racemelike or paniclelike, pedunculate. Flowers bisexual or, rarely, bisexual and staminate on same plant, 2–6 per ocreate fascicle, heterostylous or homostylous, base stipelike; perianth nonaccrescent, white, pale pink, or green, broadly campanulate, glabrous; tepals 5, distinct, petaloid, dimorphic, outer smaller than inner; stamens 8; filaments distinct, free, glabrous; anthers white, pink, or red, oval to elliptic; styles 3, reflexed, distinct; stigmas capitate. Achenes strongly exserted, brown to dark brown or gray, sometimes mottled black, unwinged or essentially so, bluntly to sharply 3-gonous, glabrous. Seeds: embryo folded. x = 8.

Distribution

Introduced; Eurasia, e Africa, introduced elsewhere, cultivated in temperate regions worldwide.

Discussion

Species 16 (2 in the flora).

Fagopyrum esculentum and F. tataricum are cultivated widely. In North America, they often escape, but populations generally are ephemeral.

Archaeological evidence for the cultivation of buckwheat dates to 4600 bp in China and 3500 bp in Japan (O. Ohnishi 1998). Molecular studies indicate that Fagopyrum comprises two major clades, with F. esculentum and F. tataricum in the large-fruited “cymosum” group (O. Ohnishi and Y. Matsuoka 1996; Y. Yasui and O. Ohnishi 1998, 1998b; O. Ohsako and O. Ohnishi 2000).

Key

1 Achene faces smooth, angles smooth; tepals (2.5-)3-5 mm; perianths, creamy white topale pink; inflorescences paniclelike, 1-4 cm, terminal and axillary Fagopyrum esculentum
1 Achene faces irregularly rugose, angles often sinuate-dentate; tepals 1.5-3 mm; perianths,green with whitish margins; inflorescences racemelike, 2-10 cm, axillary Fagopyrum tataricum
... more about "Fagopyrum"
Harold R. Hinds† +  and Craig C. Freeman +
Miller +
Buckwheat +  and sarrasin +
Eurasia +, e Africa +, introduced elsewhere +  and cultivated in temperate regions worldwide. +
Latin fagus, beech, and Greek pyrus, wheat, alluding to resemblance of the achene to a beech-nut +
Gard. Dict. Abr. ed. +
ohnishi1996a +, ohnishi1998a +, ohsako2000a +, yasui1998a +  and yasui1998b +
Fagopyrum +
Polygonaceae subfam. Polygonoideae +