All Floras      Advanced Search
FOC Vol. 22 Page 316, 323 Login | eFloras Home | Help
FOC | Family List | FOC Vol. 22 | Poaceae

77. Avena Linnaeus, Sp. Pl. 1: 79. 1753.

燕麦属 yan mai shu

Authors: Zhen-lan Wu & Sylvia M. Phillips

Annuals. Culms erect, fairly robust. Leaf blades linear, flat; ligule membranous. Inflorescence a large loose panicle. Spikelets large, pendulous, oblong to gaping, florets 2 to several, the uppermost reduced; rachilla pilose or glabrous, disarticulating below each floret or only below the lowest, or not disarticulating (cultivated species); glumes lanceolate to elliptic, usually subequal and as long as spikelet, rarely strongly unequal or shorter than spikelet, herbaceous to membranous, 7–11-veined, back rounded, smooth, apex acuminate; floret callus acute to pungent, bearded; lemmas lanceolate-oblong, usually leathery, occasionally papery, back rounded, 5–9-veined, glabrous to hispid, awned usually from near middle of back, apex papery, 2-toothed to 2-fid, lobes sometimes extended into fine bristles, awn geniculate with twisted column, sometimes reduced or absent (cultivated species); palea usually shorter than lemma, keels ciliate. Ovary densely hairy. Caryopsis with long linear hilum.

About 25 species: centered on the Mediterranean region and SW Asia, extending to N Europe and N Asia, widely introduced to other temperate and cold regions; five species (all introduced) in China.

Avena includes several species cultivated as cereal crops (oats) and is also used for fodder and fiber production. A few species have become widespread as weeds of crops in temperate regions.

Avena barbata Pott ex Link and A. eriantha Durieu, native from the Mediterranean to C Asia, are mentioned (FRPS 9(3): 168. 1987) as cultivated in China.

1 Rachilla tough, spikelets not regularly disarticulating; cultivated plants   (2)
+ Rachilla disarticulating below each floret, or at least below lowest; wild plants   (4)
2 (1) Glumes as long as spikelet; lemmas leathery, distinctly veined in upper half; rachilla internodes short, straight; grains not free threshing   1 A. sativa
+ Glumes conspicuously shorter than spikelet; lemmas papery, distinctly veined throughout; rachilla internodes elongate, sometimes sinuous; grains free threshing   (3)
3 (2) Spikelets 2.5–3.5(–4.5) cm, florets 3–7; lemma apex shortly and obtusely 2–4-toothed; grain ca. 8 mm   2 A. chinensis
+ Spikelets 2–2.5(–3.5) cm, florets 2–4; lemma apex with 2 slenderly acuminate teeth; grain ca. 6 mm.   3 A. nuda
4 (1) Rachilla disarticulating only below lowest floret, only lowest floret with a basal callus   (5)
+ Rachilla disarticulating below each floret, each floret with a basal callus   (6)
5 (4) Lower glume ± equal to upper glume.   4 A. sterilis subsp. ludoviciana
+ Lower glume much shorter than upper glume.   A. eriantha (see note above)
6 (4) Lemma apex 2-toothed or 2-fid, but lacking apical bristles.   5 A. fatua
+ Lemma apex 2-fid, each lobe with a fine apical bristle.   A. barbata (see note above)

Lower Taxa


Related Objects  
  • Avena.pdf
  • PDF

    Flora of China @
    Browse by
    Advanced Search

    Flora of China Home




     |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |