Gramineae

禾本科

APG 4

Poaceae 禾本科

特徵描述

屬列表

標本列表

特徵描述

作者

HSU, Chien-Chang

型態特徵

Annuals or perennials herbs, rather rarely with woody perennials culms (subfamily Bambusoideae); hollow or solid, septate at nodes. Perennials herbs or their branches at base usually with scales (cataphylls, transformed leaf sheaths). Leaves two-ranked, consisting of a sheath, ligule, and a blade. Axillary buds when grown out into a branch provided with a usually 2-nerved bract (prophyll) between branch and culm. Leaf blade mostly linear and not petiolate at base, rarely with broad blades and stipitate (pseudo-petiole) at base (especially in Bambusoideae); ligules membranaceous or ciliate, rarely lacking (Echinochloa), margins of sheath of leaf connate at least at base. Inflorescences usually terminal, primarily paniculate, but secondarily extremely variable and transformed into racemes, spikes, digitate umbels, etc. Flowering unit (spikelet) usually with 2 bracteoles (glumes) at base; base occasionally with an obconical blunt to very acute thickening (callus). Flowers alternatingly along a central axis (rachilla) supported by a bract (lemma) and a prophyll (palea), bisexual or occasionally unisexual. Lemma and palea when falling as a unit clasping fruit at base often with an obconical blunt to very acute thickening (also called callus). Perianth usually composed of 2 or 3 minute scales (lodicules), rarely 6, sometimes absent (e.g. in sterile or female florets). Stamens usually 3, sometimes 6 (Bambusoideae), or 1 or 2; filaments filiform; anthers 2-locular. Pistil 1, superior; ovary and single anatropous ovule completely adnate; styles 2 or 3, apical or subapical, stigmas plumose. Caryopsis with rich endosperm; embryo basal, abaxial (facing lemma), opposite to punctiform to linear adaxial hilum (facing palea).

屬

The Gramineae are one of the largest families of vascular plants with an estimated 620 genera and 10,000 species. Keng (1965) reported 201 genera and 775 species for mainland China. Hsu (1974) treated 5 subfamilies (excluding Bambusoideae), 27 tribes, 118 genera, 289 species, 1 subspecies, 39 varieties, and 8 forms in Taiwan.

The following arrangement of subfamilies, tribes and genera is that of Hsu (1978) with very few modifications. The descriptions of most genera are unchanged in this edition except that genera of the subfamily Pooideae (Festucoideae) which was mostly adopted from Clayton and Renvoize (1986). Some critical remarks were provided by Dr. J. F. Veldkamp, National Herbarium of the Netherlands, Leiden. Some line-drawings of Paniceae were drawed by Y. Fujimoto, Botanical Institute of Fujimoto, Kobe, Japan.

參考文獻

HSU, Chien-Chang, Flora of Taiwan, second edition 5: 318. 2000. (Fl. Taiwan 2nd edit.)
Clayton, W. D. and Renvoize, S. A., Her Majestys Stationary Office. London . 1986.
Hsu, C. C., Taiwan Prov. Educ. Assoc. Taipei . 1975.
Hsu, C. C., Flora of Taiwan 5: 373-783. 1978. (Fl. Taiwan)
Koyama, T., Kodansha Ltd. Tokyo . 1987.
Kuo, P. C., Flora Reipublicae Popularis Sinicae 9(3): . 1987. (Fl. Reip. Pop. Sin.)
Osada, T., . 1993.
Watson, L. and Dallwitz, M. J., CAB International, Wallingford . 1992.

Microstegium 莠竹屬

作者

HSU, Chien-Chang

型態特徵

Annuals or perennials; culms ribbed or terete, smooth. Leaf blade suddenly narrowed at base, often petiole-like. Inflorescence consisting of several spike-like racemes digitately arranged. Racemes many noded, breaking up at maturity. Spikelets in pairs, one pedicelate, finally falling off from pedicel, other usually sessile and falling off with adjacent joint of rachis, rarely shortly pedicelate and deciduous at maturity. Spikelets oblong, dorsally compressed, usually awned, with short, bearded callus, dorsiventrally arranged; lower glume as long as spikelets or slightly shorter, apex truncate or 2-toothed, with a longitudinal depression abaxially, margins inflexed, without midnerve; upper glume as long as spikelet, boat shaped keeled, acute, acuminate or awned, 3-nerved; lower lemma, if present hyaline, nerveless; lower palea present or absent, often apparently substituting for a lower lemma; upper lemma thinly membranaceous, entire, 2-toothed or 2-lobed usually awned, awn slender, flexuous; upper palea small or wanting; lodicules 2, curieate, small; stamens 3; stigmas exserted at or below apes. Caryopsis oblong.