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.
Imperata 白茅屬
作者
HSU, Chien-Chang
型態特徵
Perennials. Rhizome with long creeping, branched, scaly with a few long internodes. Basal leaves vigorous, sheaths coriaceous, finally disintegrating into fibers; ligule short; blades erect, linear-lanceolate, gradually attenuate downwards, sometimes reduced to a stout midrib, upwards gradually tapering into an acute, usually hard, sharp point, older blades hard with serrate, silicous edges. lnflorescence a silky panicle with inarticulate axis, branched on all sides, dense, contracted, spike-like during anthesis, afterwards more spreading but still narrow, silvery white, creamy or light-yellow. Spikelets in unequally pedicelate pairs, articulate with wide, excavated apex of pedicels, oblong, muticous, at base with dense crown of glossy white hairs, hairs much longer than spikelet, at first erect, afterwards spreading, glumes subequal, thin, 3-9-nerved, rarely nerveless, long-hairy in lower half; lemma smaller, hyaline, very thin, except at base, 1-nerved or nerveless; lower palea absent; upper lemma sometimes wanting; upper palea conduplicate, broad, hyaline, nerveless, usually embracing bisexual flower; lodicules wanting; stamens 2 or 1; styles 2, connate at base, stigmas long and narrow, exserted apically. Caryopsis oblong, free; embryo 1/2 as long as caryopsis of longer.
