[14][21] Which is the larger family is unclear, because of the uncertainty about how many extant species each family includes. [22], The name Asteraceae (English: /ˌæstəˈreɪsi, -siˌaɪ, -siˌeɪ, -siˌiː/) comes to international scientific vocabulary from New Latin, from Aster, the type genus, + -aceae,[23] a standardized suffix for plant family names in modern taxonomy. Some marginal florets may have no petals at all (filiform floret). It is estimated that the crown group of Asteraceae evolved at least 85.9 myr (Late Cretaceous, Santonian) with a stem node age of 88–89 myr (Late Cretaceous, Coniacian). This is because the petals open at dawn and close at dusk. The style has two lobes. [33] Pollen from ragweed Ambrosia is among the main causes of so-called hay fever in the United States. Solidago produces relatively high protein pollen, which helps honey bees over winter. Bell-shaped disk florets form the centre of each head. [5][clarification needed What other shared characteristics?] There are usually five stamens. [24] It refers to the "composite" nature of the capitula, which consist of a few or many individual flowers. [8]:29 The individual heads have the smaller individual flowers arranged on a round or dome-like structure called the receptacle. The florets have five petals fused at the base to form a corolla tube and they may be either actinomorphic or zygomorphic. Asteraceae is an economically important family, providing food staples, garden plants, and herbal medicines. There are many apomictic species in the family. Explore the health benefits of dandelion and its various use in the kitchen Bidens) or entire capitulum (e.g. Asteraceae is the largest family of medicinal and aromatic plants in Uttarakhand. Cypsela morphology is often used to help determine plant relationships at the genus and species level. Worldwide. [31] Parthenium argentatum (guayule) is a source of hypoallergenic latex. Cape provinces, South Africa. [8][9] Sometimes ray flowers may be slightly off from radial symmetry, or weakly bilaterally symmetric, as in the case of desert pincushions Chaenactis fremontii. The primary common characteristic is the existence of sometimes hundreds of tiny individual florets which are held together by protective involucres in flower heads, or more technically, capitula. [34], Asteraceae are also used for some industrial purposes. Corrections? The phyllaries can be free or fused, and arranged in one to many rows, overlapping like the tiles of a roof (imbricate) or not (this variation is important in identification of tribes and genera). For family names, the modern tendency in taxonomy is to use the name of a familiar plant in a certain family and to add the suffix -aceae to the name. Characteristics of this Plant Family: Leaves, Stem & Roots ~ The leaves of this family are often undivided and spoon-shaped, but they are sometimes toothed or divided, and they may be prickly. A ligulate flower is a 5-tipped, strap-shaped, individual flower in the heads of other members. 4. Most occur in hot desert and cold or hot semi-desert climates, and they are found on every continent but Antarctica. [9] A disk flower (or disc flower) is a radially symmetric (i.e., with identical shaped petals arranged in circle around the center) individual flower in the head, which is ringed by ray flowers when both are present. The species of the family are growing from low altitude of Tarai Bhabar to the alpine. In members of the Asteraceae the fruit is achene-like, and is called a cypsela (plural cypselae). The wormwood genus Artemisia includes absinthe (A. absinthium) and tarragon (A. dracunculus). Species outside of their native ranges can be considered weedy or invasive. Members of the Asteraceae are mostly herbaceous plants, but some shrubs, vines, and trees (such as Lachanodes arborea) do exist. They have a unique type of inflorescence consisting of many tiny flowers aggregated together in a flower head (a capitulum) that forms a false "flower." Most of them are xerophytes, hydrophytes and semi-aquatic. Gochnatioideae: 4 or 5 genera, 90 species. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae were first described in 1740. Family: Asteraceae; Compositae; Common name: sunflower family [Zomlefer, pp. The apparent seeds of the sunflower, for example, are actually achenes. Depending on the tribe, the inflorescence may consist of ray flowers, disk flowers, or both ray and disk flowers. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. About half of the species are native to the Old World and half are native to the New World. These are herbs, shrubs or trees. unknown whether the precise cause of their great success was the development of the highly specialised capitulum, their ability to store energy as fructans (mainly inulin), which is an advantage in relatively dry zones, or some combination of these and possibly other factors. The stems can contain secretory canals with resin,[6] or latex which is particularly common among the Cichorioideae.[7]. Members of the family have flower heads composed of many small flowers, called florets, that are surrounded by bracts (leaflike structures). They may simulate the sepals of the pseudanthium. Artichokes (Cynara), lettuce (Lactuca), endive (Cichorium), and salsify (Tragopogon) are commonly eaten as vegetables, and the edible seeds of safflower (Carthamus), and sunflower (Helianthus) are used in the production of cooking oils. The word "aster" means "star" in Greek, referring to the appearance of some family members, as a "star" surrounded by "rays". Let us know if you have suggestions to improve this article (requires login). Asteraceae, also called Compositae, the aster, daisy, or composite family of the flowering-plant order Asterales. Most species of Asteraceae are annual, biennial, or perennial herbaceous plants, but there are also shrubs, vines, and trees. [28], Asteraceae is an economically important family, providing products such as cooking oils, leaf vegetables like lettuce, sunflower seeds, artichokes, sweetening agents, coffee substitutes and herbal teas. [citation needed], Asteraceae species have a widespread distribution, from subpolar to tropical regions in a wide variety of habitats. [14], Asteraceae produce secondary metabolites, such as flavonoids and terpenoids. Characteristic features and economic importance of family Compositae or Asteraceae. The whitish fluffy head of a dandelion, commonly blown on by children, is made of the pappus, with tiny seeds attached at the ends, whereby the pappus provides a parachute like structure to help the seed be carried away in the wind. A set of bracts forms an involucre surrounding the base of the capitulum. The margins also can be entire or toothed. Corymbioideae: Only the genus Corymbium, with 9 species. The corolla of the ray flower may have 2 tiny teeth opposite the 3-lobed strap, or tongue, indicating evolution by fusion from an originally 5-part corolla. Wormwood (Artemisia) is the source of the poisonous oil used to give the liqueur absinthe its distinctive character. This family has about 25,000 different plant species, including many different varieties of daisy and aster, as well as the sunflower, yarrow, goldenrod, and dahlia. [8], A radiate head has disc flowers surrounded by ray flowers. Pertyoideae: 5 or 6 genera, 70 species. Characteristics The family is characterized by having a capitulum or head, an inferior, unilocular ovary with one ovule, and with few exceptions fused anthers surrounding the style. Pollen is released inside the tube and is collected around the growing style, and then, as the style elongates, is pushed out of the tube (nüdelspritze). The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Echinacea is used as a medicinal tea. [8], The "petals" or "sunrays" in a sunflower head are actually individual strap-shaped[9] flowers called ray flowers, and the "sun disk" is made of smaller circular shaped individual flowers called disc flowers. The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Staminate heads have all male flowers. [citation needed], Plants are used as herbs and in herbal teas and other beverages. Ray florets are always highly zygomorphic and are characterised by the presence of a ligule, a strap-shaped structure on the edge of the corolla tube consisting of fused petals. Asteraceae species are generally easy to distinguish from other plants because of their unique inflorescence and other shared characteristics. Southwestern United States. Asteraceae pollens are mostly rounded triangular to square amb, sometimes circular in polar view and prolate in equatorial view. [citation needed], Members of the family Asteraceae generally produce taproots, but sometimes they possess fibrous root systems. Taxonomy Asteraceae The rooting of the Tree of Life, and the relationships of the major lineages, are controversial. Leaves can be alternate, opposite, or whorled. Please select which sections you would like to print: While every effort has been made to follow citation style rules, there may be some discrepancies. [citation needed] Dandelion was introduced into North America by European settlers who used the young leaves as a salad green. [16]:117–118 Traditionally, two subfamilies were recognised: Asteroideae (or Tubuliflorae) and Cichorioideae (or Liguliflorae). Several genera are of horticultural importance, including pot marigold (Calendula officinalis), Echinacea (coneflowers), various daisies, fleabane, chrysanthemums, dahlias, zinnias, and heleniums. They are annual garden herbs. Purple coneflower (Echinacea purpurea) belongs to the Asteraceae family and bears dailylike flowers on straight stems above clumps of dense foliage. The plants of this family are unique and have root nodules which contain nitrogen-fixing symbiotic bacteria, capable of transforming atmospheric nitrogen into fixed nitrogen or ammonia. When a sunflower family flower head has only disc flowers that are sterile, male, or have both male and female parts, it is a discoid head. [1] Barreda, et al. [citation needed] The latter has been shown to be extensively paraphyletic, and has now been divided into 12 subfamilies, but the former still stands. Taproots are modified into tubers. With advances in molecular biology, in the 1980s, molecular studies were carried out in this family, one of the first being reported by Jansen and Palmer (1987) , which noted the similarity between the organization of the structure of DNA. Many of these characteristics are homologous for the entire group, whether comparing a blue whale to an amoeba or a human to a giant redwood tree. Inflorescence is a compact head (capitulum), surrounded by involucral bracts. The stem might be erect, hairy, woody or prostrate. Cichorioideae: 224 genera, 3,200 species. Several other members of Asteraceae have economic importance as food crops. Leaves: Petiolate; alternate or opposite; simple; exstiputate; Inflorescence: Capitulum surrounded at the bases by a group of involucres. Allergy to these compounds is the leading cause of allergic contact dermatitis in florists in the US. They commonly have basal and/or apical appendages. Omissions? Wunderlichioideae: 8 genera, 24 species. With more than 1,620 genera and 23,600 species of herbs, shrubs, and trees distributed throughout the world, Asteraceae is one of the largest plant families. They are surrounded by involucral bracts, and when viewed from a distance, each capitulum may appear to be a single flower. aster family. [35], A typical Asteraceae flower head showing the individual flowers (, A flower head showing the individual flowers opening from the outside (, Learn how and when to remove this template message, "Early evolution of the angiosperm clade Asteraceae in the Cretaceous of Antarctica", "Family: Asteraceae Bercht. Absent from Europe, mostly in South America. [5], The oldest known fossils of members of Asteraceae are pollen grains from the Late Cretaceous of Antarctica, dated to ∼76–66 myr (Campanian to Maastrichtian) and assigned to the extant genus Dasyphyllum. [12] The mature seeds usually have little endosperm or none. In the present study, the important role of Asteraceae family plants was investigated in terms of their traditional records for wound healing purposes (Table 1) … [14] Heterocarpy, or the ability to produce different fruit morphs, has evolved and is common in Asteraceae. [8][9] Sometimes a ray flower is 2-tipped (2-lobed). In this way the family name Asteraceae is made up by using the name Aster and adding -aceae. Paleobotanists suggest that the first members of this family may have evolved in Argentina some 50 million years ago, based on the discovery of well-preserved fossils that date to the Eocene Epoch (56 million to 33.9 million years ago). In plants of the family Asteraceae, what appears to be a single flower is actually a cluster of much smaller flowers. The flowers mature first at the outside, moving toward the center, with the youngest in the middle. Nearly all Asteraceae bear their flowers in dense flower heads called capitula. Characteristics and economic importance of family Liliaceae. Next. Characteristic of pollen grains: Asteraceae: ... Pollen grains in Asteraceae family are relatively stenopalynous with less variation exhibited in the pollen morphology. The latter is the only kind of floret in the Carduoideae, while the first kind is more widespread. They may be simple, but are often deeply lobed or otherwise incised, often conduplicate or revolute. Economic Uses: -The importance of the Asteraceae is Enlarged outer (peripheral) flowers in the capitulum may resemble petals, and the involucral bracts may look like a calyx.