|
__NOTOC__ A raceme ( or ) is an unbranched, indeterminate type of inflorescence bearing ''pedicellate'' flowers — flowers having short floral stalks called pedicels — along its axis. In botany, an ''axis'' means a shoot, in this case one bearing the flowers. In indeterminate inflorescence-like racemes, the oldest flowers are borne towards the base and new flowers are produced as the shoot grows, with no predetermined growth limit.〔 A plant that flowers on a showy raceme may have this reflected in its scientific name, e.g. ''Cimicifuga racemosa''. A compound raceme, also called a panicle, has a branching main axis.〔 Examples of racemes occur on mustard (genus ''Brassica'') and radish (genus ''Raphanus'') plants.〔 A spike is an unbranched, indeterminate inflorescence, similar to a raceme, but bearing sessile flowers (sessile flowers are attached directly, without stalks).〔 Examples occur on Malabar nut (''Justicia adhatoda'') and chaff flowers (genus ''Achyranthes'').〔 A spikelet can refer to a small ''spike'', although it is primarily used to refer to the ultimate flower cluster unit in grasses (family Poaceae) and sedges (family Cyperaceae), in which case the stalk supporting the cluster becomes the ''pedicel''. A true spikelet comprises one or more florets enclosed by two glumes (sterile bracts), with flowers and glumes arranged in two opposite rows along the spikelet.〔 Examples occur on rice (species ''Oryza sativa'') and wheat (genus ''Triticum''), both grasses.〔 An ament or catkin is very similar to a spike or raceme, “but with subtending bracts so conspicuous as to conceal the flowers until pollination, as in the pussy–willow, alder, () birch...”. These are sometimes called amentaceous plants.〔 A spadix is a form of spike in which the florets are densely crowded along a fleshy axis, and enclosed by one or more large, brightly–colored bracts called spathes. Usually the female flowers grow at the base, and male flowers grow above.〔 They are a characteristic of the Araceae family, for example jack–in–the–pulpit (species ''Arisaema triphyllum'') and wild calla (genus Calla).〔 ==Examples== Image:Traube (inflorescence).svg| Image:Inflorescences Spike Kwiatostan Kłos.svg| Image:Kolben (inflorescence).svg| Image:Spathoglottis flwrs reduced.jpg|The inflorescence of ''Spathoglottis plicata'', a terrestrial orchid, is a typical raceme Image:Pycreus.jpg|Every radiating unit in this inflorescence of a ''Cyperus'' sedge is a spikelet composed of small flowers (florets) arranged in two ranks 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Raceme」の詳細全文を読む スポンサード リンク
|