{{Short description|Flowers on short stalks along the stem}} {{About|the botanical term|mixtures of chiral compounds in chemistry|Racemates}} {{Use dmy dates|date=October 2024}} [[File:Phalaenopsis - Feburary 2022 - Sarah Stierch 02.jpg|thumb|right|The inflorescence of a ''Phalaenopsis'' orchid is a typical raceme.]]
A '''raceme''' ({{IPAc-en|r|eɪ|ˈ|s|iː|m|,_|r|ə|-}}) or '''racemoid''' is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the shoot grows in height, with no predetermined growth limit. Examples of racemes occur on mustard (genus ''Brassica''), radish (genus ''Raphanus''), and orchid (genus ''Phalaenopsis'') plants.
== Definition == A ''raceme'' or ''racemoid'' is an unbranched, indeterminate type of inflorescence bearing pedicellate flowers (flowers having short floral stalks called ''pedicels'') along its axis.<ref name=walters1996>{{cite book |last1=Walters |first1=Dirk R. |last2=Keil |first2=David J. |title=Vascular Plant Taxonomy |url=https://archive.org/details/vascularplanttax00walt |url-access=registration |edition=4th |date=1 January 1996 |publisher=Kendall/Hunt Publishing Company |location=United States |isbn=978-0-7872-2108-9 |page=[https://archive.org/details/vascularplanttax00walt/page/602 602] }}</ref> In botany, an ''axis'' means a shoot, in this case one bearing the flowers. In indeterminate inflorescence-like racemes, the oldest flowers grow close to the base and new flowers are produced as the shoot grows in height, with no predetermined growth limit.<ref name="Wofford1989"/> A plant that flowers on a showy raceme may have this reflected in its scientific name, e.g. the species ''Actaea 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.<ref name="KumarBhatia"/>
=== Spike === A '''spike''' is an unbranched, indeterminate inflorescence, similar to a raceme, but bearing sessile flowers (sessile flowers are attached directly, without stalks).<ref name="Wofford1989"/> Examples occur on Malabar nut (''Justicia adhatoda'') and chaff flowers (genus ''Achyranthes'').<ref name="KumarBhatia"/> A '''spikelet''' can refer to a small spike, although it primarily refers to the ultimate flower cluster unit in grasses (family Poaceae) and sedges (family Cyperaceae),<ref name="Wofford1989">{{cite book |last=Wofford |first=B. Eugene |title=Guide to the Vascular Plants of the Blue Ridge |url=https://books.google.com/books?id=mNeNUQkIrqQC&pg=PA12 |year=1989 |publisher=University of Georgia Press |isbn=978-0-8203-2455-5 |pages=10–15 }}</ref> 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.<ref name="KumarBhatia"/>
=== Catkin === 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, [and] birch". These are sometimes called ''amentaceous plants''.<ref name="GilmanPeck1907">{{cite book |editor=Gilman, Daniel Coit. |others=Peck, Harry Thurston; Colby, Frank Moore |title=The new international encyclopædia |url=https://books.google.com/books?id=pppGAQAAIAAJ&pg=PA618 |volume=10 |year=1907 |publisher=Dodd, Mead and Company |location=New York |page=618 }}</ref>
=== Spadix === 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.<ref name="KumarBhatia">{{cite book |last1=Kumar |first1=Vinay |last2=Bhatia |first2=S. S. |title=Complete Biology for Medical College Entrance Examination |url=https://books.google.com/books?id=kTdVAQAAQBAJ&pg=PA218 |edition=3rd |series=McGraw Hill Education Series |year=2013 |publisher=McGraw Hill Education (India) Private Limited |isbn=978-1-259-06430-2 |page=218 }}</ref> They are a characteristic of the family Araceae, for example jack-in-the-pulpit (species ''Arisaema triphyllum'') and wild calla (genus ''Calla'').<ref name="GilmanPeck1907"/>
==Examples== <gallery perrow="4"> File:Traube (inflorescence).svg|{{center|Raceme}} File:Inflorescences Spike Kwiatostan Kłos.svg|{{center|Spike}} File:Kätzchen (inflorescence).svg|{{Center|Catkin}} File:Kolben (inflorescence).svg|{{center|Spadix}} File:Spathoglottis flwrs reduced.jpg|The inflorescence of ''Spathoglottis plicata'', a terrestrial orchid, is a typical raceme File:Backlit xeronema flower raceme.jpg|Tightly packed raceme of ''Xeronema callistemon'', with prominent red stamens File:Pycreus.jpg|Every radiating unit in this inflorescence of a ''Cyperus'' sedge is a spikelet composed of small flowers (florets) arranged in two ranks </gallery>
==Etymology== From classical Latin, a ''racemus'' is a cluster of grapes.<ref>Oxford English Dictionary. Raceme 2. Bot. A type of inflorescence in which the flowers are arranged on short, nearly equal, lateral pedicels, at equal distances along a single elongated axis</ref>
==See also== * Inflorescence * Glossary of botanical terms
==References== {{Reflist}} {{Commons category}}
{{botany|state=collapsed}} {{Authority control}}
Category:Flowers Category:Plant morphology