Raceme

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The inflorescence of Vanda garayi, an epiphytic orchid, is a typical raceme. Vanda garayi.png
The inflorescence of Vanda garayi , an epiphytic orchid, is a typical raceme.

A raceme ( /rˈsm,rə-/ ) 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 ) and radish (genus Raphanus ) plants.

Contents

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. [1] 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. [2] A plant that flowers on a showy raceme may have this reflected in its scientific name, e.g. the species 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. [3]

Spike

A Spike (botany) is an unbranched, indeterminate inflorescence, similar to a raceme, but bearing sessile flowers (sessile flowers are attached directly, without stalks). [2] Examples occur on Malabar nut ( Justicia adhatoda ) and chaff flowers (genus Achyranthes ). [3] 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), [2] 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. [3]

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. [4]

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. [3] They are a characteristic of the family Araceae, for example jack–in–the–pulpit (species Arisaema triphyllum ) and wild calla (genus Calla ). [4]

Examples

Etymology

From classical Latin, a racemus is a cluster of grapes. [5]

See also

Related Research Articles

<i>Amorphophallus</i> Genus of flowering plants

Amorphophallus is a large genus of some 200 tropical and subtropical tuberous herbaceous plants from the Arum family (Araceae), native to Asia, Africa, Australia and various oceanic islands. A few species are edible as "famine foods" after careful preparation to remove irritating chemicals. The genus includes the Titan arum of Indonesia, which has the largest inflorescence of any plant in the genus, and is also known as the 'corpse flower' for the pungent odour it produces during its flowering period, which can take up through seven years of growth before it occurs.

<span class="mw-page-title-main">Inflorescence</span> Term used in botany to describe a cluster of flowers

An inflorescence, in a flowering plant, is a group or cluster of flowers arranged on a stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a main axis (peduncle) and by the timing of its flowering.

<span class="mw-page-title-main">Panicle</span> Term used in botany to describe a branching of flower heads

A panicle is a much-branched inflorescence. Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers be pedicellate. The branches of a panicle are often racemes. A panicle may have determinate or indeterminate growth.

<span class="mw-page-title-main">Spadix (botany)</span>

In botany, a spadix is a type of inflorescence having small flowers borne on a fleshy stem. Spadices are typical of the family Araceae, the arums or aroids. The spadix is typically surrounded by a leaf-like curved bract known as a spathe. For example, the "flower" of the well known Anthurium spp. is a typical spadix with a large colorful spathe.

<span class="mw-page-title-main">Bract</span> Modified or specialized leaf

In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture. Typically, they also look different from the parts of the flower, such as the petals or sepals. A plant having bracts is referred to as bracteate or bracteolate, while one that lacks them is referred to as ebracteate and ebracteolate, without bracts.

<i>Andropogon gerardi</i> Species of grass

Andropogon gerardi, commonly known as big bluestem, is a species of tall grass native to much of the Great Plains and grassland regions of central and eastern North America. It is also known as tall bluestem, bluejoint, and turkeyfoot.

<span class="mw-page-title-main">Indeterminate growth</span>

In biology and botany, indeterminate growth is growth that is not terminated in contrast to determinate growth that stops once a genetically pre-determined structure has completely formed. Thus, a plant that grows and produces flowers and fruit until killed by frost or some other external factor is called indeterminate. For example, the term is applied to tomato varieties that grow in a rather gangly fashion, producing fruit throughout the growing season. In contrast, a determinate tomato plant grows in a more bushy shape and is most productive for a single, larger harvest, then either tapers off with minimal new growth or fruit or dies.

<i>Raphanus raphanistrum</i> Species of flowering plant

Raphanus raphanistrum, also known as wild radish, white charlock or jointed charlock, is a flowering plant in the family Brassicaceae. One of its subspecies, Raphanus raphanistrum subsp. sativus, includes a diverse variety of cultivated radishes. The species is native to western Asia, Europe and parts of Northern Africa. It has been introduced into most parts of the world and is regarded as a habitat threatening invasive species in many areas, for example, Australia. It spreads rapidly and is often found growing on roadsides or in other places where the ground has been disturbed.

<span class="mw-page-title-main">Spikelet</span> Part of a spike inflorescence of a grass or sedge

A spikelet, in botany, describes the typical arrangement of the flowers of grasses, sedges and some other monocots.

This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnifying lens. This page provides help in understanding the numerous other pages describing plants by their various taxa. The accompanying page—Plant morphology—provides an overview of the science of the external form of plants. There is also an alphabetical list: Glossary of botanical terms. In contrast, this page deals with botanical terms in a systematic manner, with some illustrations, and organized by plant anatomy and function in plant physiology.

This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary of leaf morphology. For other related terms, see Glossary of phytopathology, Glossary of lichen terms, and List of Latin and Greek words commonly used in systematic names.

<i>Redfieldia</i> Genus of grasses

Redfieldia, known as blowout grass, is a monotypic genus in the grass family (Poaceae). The sole species, Redfieldia flexuosa, is native to sandhills in the western and central United States. The plants grow in small clusters, protecting each other from the harsh desert conditions.

<i>Corymbium</i> Genus of perennial plants from South Africa

Corymbium is a genus of flowering plants in the daisy family comprising nine species. It is the only genus in the subfamily Corymbioideae and the tribe Corymbieae. The species have leaves with parallel veins, strongly reminiscent of monocots, in a rosette and compounded inflorescences may be compact or loosely composed racemes, panicles or corymbs. Remarkable for species in the daisy family, each flower head contains just one, bisexual, mauve, pink or white disc floret within a sheath consisting of just two large involucral bracts. The species are all endemic to the Cape Floristic Region of South Africa, where they are known as plampers.

<i>Oplismenus compositus</i> Species of flowering plant

Oplismenus compositus, the running mountaingrass, is a species of perennial plant from the family Poaceae that can be found throughout Asia, Africa, Australia, South America, Mexico and Hawaii.

Oplismenus thwaitesii is a flowering plant that is endemic to India.

<i>Rytidosperma bipartitum</i> Species of grass

Rytidosperma bipartitum, the leafy wallaby grass, is a perennial species of grass found in south eastern Australia. Usually found on the heavier clay or on loamy soils in open eucalyptus woodland. The habit is somewhat variable, erect and densely tufted. The grass may grow up to 0.7 m tall.

<i>Ischaemum rugosum</i> Species of grass

Ischaemum rugosum, also known as saramollagrass, is a flowering plant belonging to the grass family Poaceae in the genus Ischaemum, and is native to tropical and temperate regions of Asia, growing in marshes and other wet habitats. It is a vigorous annual, and is an invasive species in South America and Madagascar. It reaches heights of up to 1 m and is primarily recognized by the ridged surface of its sessile spikelet’s lower glume. Despite its historic importance as fodder in Asia, the grass has become a major weed in mid-latitude rice paddies throughout Asia and South America.

Salix delavayana is a shrub or small tree from the genus willow (Salix) with mostly 3 to 8 centimeters long leaf blades. The natural range of the species is in the south of China and in Tibet.

Salix dissa is a low shrub from the genus willow (Salix) with usually 1 to 3 centimeters long leaf blades. The natural range of the species is in China.

<i>Cyperus serotinus</i> Species of sedge

Cyperus serotinus is a species of sedge that is native to parts of Europe and Asia.

References

  1. Walters, Dirk R.; Keil, David J. (1 January 1996). Vascular Plant Taxonomy (4th ed.). United States: Kendall/Hunt Publishing Company. p.  602. ISBN   978-0-7872-2108-9.
  2. 1 2 3 Wofford, B. Eugene (1989). Guide to the Vascular Plants of the Blue Ridge. University of Georgia Press. pp. 10–15. ISBN   978-0-8203-2455-5.
  3. 1 2 3 4 Kumar, Vinay; Bhatia, S. S. (2013). Complete Biology for Medical College Entrance Examination. McGraw Hill Education Series (3rd ed.). McGraw Hill Education (India) Private Limited. p. 218. ISBN   978-1-259-06430-2.
  4. 1 2 Gilman, Daniel Coit., ed. (1907). The new international encyclopædia. Vol. 10. Peck, Harry Thurston; Colby, Frank Moore. New York: Dodd, Mead and Company. p. 618.
  5. 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