Floral axis

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The floral axis (sometimes referred to as the receptacle) is the area of the flower upon which the reproductive organs and other ancillary organs are attached. It is also the point at the center of a floral diagram. Many flowers in division Angiosperma appear on floral axes. The floral axis can differ in form depending on the type of plant. For example, monocotyledons have a weakly developed floral axis compared to dicotyledons, and will therefore rarely possess a floral disc, which is common among dicotyledons. [1]

Contents

Floral diagramming

A typical example of a floral diagram. The floral axis (receptacle) is the circle in the middle, surrounded by staminodes, petals, and sepals. The main axis is the circle at the top of the diagram Floral diagram -- Pyrus communis.svg
A typical example of a floral diagram. The floral axis (receptacle) is the circle in the middle, surrounded by staminodes, petals, and sepals. The main axis is the circle at the top of the diagram

Floral diagramming is a method used to graphically describe a flower. In the context of floral diagramming, the floral axis represents the center point around which the diagram is oriented. [3] The floral axis can also be referred to as the receptacle in floral diagrams or when describing the structure of the flower. [4] The main or mother axis in floral diagrams is not synonymous with the floral axis, rather it refers to where the stem of the flower is in relation to the diagram. The floral axis is also useful for identifying the type of symmetry that a flower exhibits. [5]

Function

The floral axis serves as the attachment point for organs of the flower, such as the reproductive organs (pistil and stamen) and other organs, such as the sepals and carpels. [6] The floral axis acts much like a modified stem and births the organs that are attached to it. [7] The fusion of a plant's organs and the amount of organs that are developed from the floral axis largely depends on the determinateness of the floral axis. [8] The floral axis does perform different functions for different types of plants. For instance, with dicotyledons, the floral axis acts as a nectary, while that is not the case with monocotyledons. [1] More specialized functions can also be performed by the floral axis. For example, in the plant Hibiscus, the floral axis is able to proliferate and produce fruit, rendering processes like self pollination unnecessary. [9]

A diagram of a flower showing the different organs and their placement on the flower. Mature flower diagram.svg
A diagram of a flower showing the different organs and their placement on the flower.

Related Research Articles

<span class="mw-page-title-main">Monocotyledon</span> Clade of flowering plants

Monocotyledons, commonly referred to as monocots, are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of the major groups into which the flowering plants have traditionally been divided; the rest of the flowering plants have two cotyledons and are classified as dicotyledons, or dicots.

<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.

<i>Amborella</i> Species of shrub

Amborella is a monotypic genus of understory shrubs or small trees endemic to the main island, Grande Terre, of New Caledonia in the southwest Pacific Ocean. The genus is the only member of the family Amborellaceae and the order Amborellales and contains a single species, Amborella trichopoda. Amborella is of great interest to plant systematists because molecular phylogenetic analyses consistently place it as the sister group to all other flowering plants, meaning it was the earliest group to evolve separately from all other flowering plants.

<i>Austrobaileya</i> Genus of plants in the family Austrobaileyaceae

Austrobaileya is the sole genus consisting of a single species that constitutes the entire flowering plant family Austrobaileyaceae. The species Austrobaileya scandens grows naturally only in the Wet Tropics rainforests of northeastern Queensland, Australia.

<span class="mw-page-title-main">Gynoecium</span> Female organs of a flower

Gynoecium is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of pistils and is typically surrounded by the pollen-producing reproductive organs, the stamens, collectively called the androecium. The gynoecium is often referred to as the "female" portion of the flower, although rather than directly producing female gametes, the gynoecium produces megaspores, each of which develops into a female gametophyte which then produces egg cells.

<span class="mw-page-title-main">Stigma (botany)</span> Part of a flower

The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower.

<span class="mw-page-title-main">Nectar</span> Sugar-rich liquid produced by many flowering plants, that attracts pollinators and insects

Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists, which in turn provide herbivore protection. Common nectar-consuming pollinators include mosquitoes, hoverflies, wasps, bees, butterflies and moths, hummingbirds, honeyeaters and bats. Nectar plays a crucial role in the foraging economics and evolution of nectar-eating species; for example, nectar foraging behavior is largely responsible for the divergent evolution of the African honey bee, A. m. scutellata and the western honey bee.

<span class="mw-page-title-main">Chloranthaceae</span> Family of flowering plants

Chloranthaceae is a family of flowering plants (angiosperms), the only family in the order Chloranthales. It is not closely related to any other family of flowering plants, and is among the early-diverging lineages in the angiosperms. They are woody or weakly woody plants occurring in Southeast Asia, the Pacific, Madagascar, Central and South America, and the West Indies. The family consists of four extant genera, totalling about 77 known species according to Christenhusz and Byng in 2016. Some species are used in traditional medicine. The type genus is Chloranthus. The fossil record of the family, mostly represented by pollen such as Clavatipollenites, extends back to the dawn of the history of flowering plants in the Early Cretaceous, and has been found on all continents.

<span class="mw-page-title-main">Flower</span> Reproductive structure in flowering plants

A flower, also known as a bloom or blossom, is the reproductive structure found in flowering plants. Flowers consist of a combination of vegetative organs – sepals that enclose and protect the developing flower, petals that attract pollinators, and reproductive organs that produce gametophytes, which in flowering plants produce gametes. The male gametophytes, which produce sperm, are enclosed within pollen grains produced in the anthers. The female gametophytes are contained within the ovules produced in the carpels.

<span class="mw-page-title-main">Pseudanthium</span> Type of inflorescence, clusters of flowers

A pseudanthium is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers, or capitula, which are special types of inflorescences in which anything from a small cluster to hundreds or sometimes thousands of flowers are grouped together to form a single flower-like structure. Pseudanthia take various forms. The real flowers are generally small and often greatly reduced, but the pseudanthium itself can sometimes be quite large.

<span class="mw-page-title-main">Floral diagram</span> Formal schematic description of floral anatomy

Floral diagram is a graphic representation of flower structure. It shows the number of floral organs, their arrangement and fusion. Different parts of the flower are represented by their respective symbols. Floral diagrams are useful for flower identification or can help in understanding angiosperm evolution. They were introduced in the late 19th century and are generally attributed to A. W. Eichler.

<i>Cleomella oxystyloides</i> Genus of flowering plants

Cleomella oxystyloides is a species of flowering plants in the cleome family, Cleomaceae, which is known by the common name spiny caper. It is native to the Mojave Desert straddling the border between California and Nevada. It grows in rocky and sandy desert habitat, often on alkaline soils. This is an annual herb producing an erect, branching stem which may reach 1.5 meters in height. The leaf is made up of three thick, firm leaflets 2 to 6 centimeters long, borne on a stout, straight petiole. The inflorescence is a dense head of flowers clustered about the stem at the leaf axils, each flower with four small yellow petals. The fruit is a small white or purple nutlet bearing the spine-like remnant of the flower receptacle.

<span class="mw-page-title-main">Lilioid monocots</span> Grade of flowering plant orders, within Lilianae

Lilioid monocots is an informal name used for a grade of five monocot orders in which the majority of species have flowers with relatively large, coloured tepals. This characteristic is similar to that found in lilies ("lily-like"). Petaloid monocots refers to the flowers having tepals which all resemble petals (petaloid). The taxonomic terms Lilianae or Liliiflorae have also been applied to this assemblage at various times. From the early nineteenth century many of the species in this group of plants were put into a very broadly defined family, Liliaceae sensu lato or s.l.. These classification systems are still found in many books and other sources. Within the monocots the Liliaceae s.l. were distinguished from the Glumaceae.

<span class="mw-page-title-main">Floral formula</span> Notation representing flowers structure

A floral formula is a notation for representing the structure of particular types of flowers. Such notations use numbers, letters and various symbols to convey significant information in a compact form. They may represent the floral form of a particular species, or may be generalized to characterize higher taxa, usually giving ranges of numbers of organs. Floral formulae are one of the two ways of describing flower structure developed during the 19th century, the other being floral diagrams. The format of floral formulae differs according to the tastes of particular authors and periods, yet they tend to convey the same information.

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John Henry Schaffner (1866–1939) was an American botanist and professor at Ohio State University. He is known for his contributions to the floral diagram and for his work on reduction division. Schaffner is the botanical authority, for seven taxa that bear his name, such as Equisetum kansanum J.H.Schaffn..

<span class="mw-page-title-main">Monocotyledon reproduction</span> Flowering plant reproduction system

The monocots are one of the two major groups of flowering plants, the other being the dicots. In order to reproduce they utilize various strategies such as employing forms of asexual reproduction, restricting which individuals they are sexually compatible with, or influencing how they are pollinated. Nearly all reproductive strategies that evolved in the dicots have independently evolved in monocots as well. Despite these similarities and their close relatedness, monocots and dicots have distinct traits in their reproductive biologies.

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References

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  2. "Floral diagrams and formulae • Floral diagram generator". herba.msu.ru. Retrieved 2018-04-11.
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  6. "Floral axis | plant anatomy". Encyclopedia Britannica. Retrieved 2018-04-11.
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  8. Schaffner, John H. (1937). "The Fundamental Nature of the Flower". Bulletin of the Torrey Botanical Club. 64 (9): 569–582. doi:10.2307/2481128. JSTOR   2481128.
  9. Bergman, H. F. (1932-07-01). "INTRACARPELLARY FRUITS AND OTHER CENTRAL PROLIFERATIONS OF THE FLORAL AXIS IN HIBISCUS". American Journal of Botany. 19 (7): 600–603. doi:10.1002/j.1537-2197.1932.tb08845.x. ISSN   1537-2197.