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Poaceae (R. Brown) Barnhart
Grass Family
禾本科
Authors: Chang-Sheng Kuoh
Gramineae Adans.
Annual or perennial herbs, rather rarely with woody perennial culms (subfamily Bambusoideae); hollow or solid, septate at the nodes. Leaves two-ranked, consisting of the sheaths, ligules and the blades. Leaf-blades mostly linear and not petiolate at base, rarely with broad blades and stipitate at base (subfamily Bambusoideae); ligules membranous or ciliate, rarely lacking (Echinochloa), leaf-sheaths clothed at the internodes. Flowers bisexual or occasionally unisexual, without distinct perianth, it representing by 2 or 3 small scales, the lodicules, rarely six or sometimes absent; stamen mostly 3, rarely variable numbers, with filiform filaments and 2-celled anthers; pistil 1, ovary 1-loculed, containg 1 anatropous ovule, the style with plumose stigmas. Fruit mostly a caryopsis with rich endosperm, the embryo at the base opposite to punctiform or linear hilum which facing the palea. Flowers sessile between abaxial lemma and adaxial palea, constituting a floret. One to many florets dispoded alternatly on the oppostie sides of rachilla, in addition with a pair of empty glumes at the base forming a spikelet. Inflorescence with spikelets as an unit aggregate into panicle, raceme or spikes.
Hsu(1974) treated 5 subfamilies (excluding Bambusoideae), 27 tribes, 118 genera, 289 species, 1 subspecies, 39 varieties, and 8 forms in Taiwan.
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subfam.3. Festucoideae
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| 1 |
Ovary with a hairy appendage at the apex; caryopsis adnate to the palea, hilum linear. |
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(2) |
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Ovary glabrous, if hairy, without hairy appendage at the apex; caryopsis not adnate to the palea. |
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(4) |
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| 2 (1) |
Spikelets pedicelled in a panicle |
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Bromeae |
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Spikelets sessile or nearly sessile on the rachis of a solitary spike or raceme. |
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(3) |
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| 3 (2) |
Spikelets shortly pedicelled, on a raceme; awn terminal |
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Brachypodieae |
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Spikelets sessile on opposite sides of the rachis |
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Triticeae |
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| 4 (1) |
Lemmas 7-11-nerved; lodicule one, fleshy, truncate |
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Meliceae |
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Lemmas mostly 5-nerved (7-11-nerved n Avena); lodicules 2, acute or acuminate. |
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(5) |
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| 5 (4) |
Spikelets one to several-flowered; lemmas not coriaceous, nerves distinct; sheaath margins adnate at least at the basal part. |
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(6) |
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Spikelets one-flowered; lemmas coriaceous, nerves not distinct; sheath margins free. |
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(7) |
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| 6 (5) |
Glumes distinct, much shorter than the lowest lemma; flowers usually more than two. |
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Festuceae |
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Glumes longer or nearly as long as the lowest lemma; florets 1, 3 or several. |
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Agrostideae |
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| 7 (5) |
Caryopsis large, with a hard beak at the apex |
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Phaenospermeae |
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Caryopsis much smaller, without a beak. |
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(8) |
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| 8 (7) |
Lemmas awnless; dorsally compressed. |
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Milieae |
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Lemmas awned, terete |
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(9) |
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| 9 (8) |
Awns trifid. |
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Aristideae |
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Awn simple, sometimes flanked by 2 bristles. |
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Stipeae |
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List of Keys
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List of lower taxa
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Treatments in Other Floras @ www.efloras.org
Other Databases
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