Gentianales is an

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants t ...

s, included within the

asterid In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total flo ...

clade of

eudicots The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons. Traditionally they were called tricolpates or non-magnoliid dicot ...

. It comprises more than 20,000 species in about 1,200 genera in 5 families. More than 80% of the species in this order belong to the family

Rubiaceae The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with interpetiolar stipules a ...

. Many of these flowering plants are used in traditional medicine. They have been used to treat pain, anxiety, cancers and neurological conditions.

Taxonomy

In the classification system of Dahlgren the Gentiales were in the

superorder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

Gentianiflorae (also called Gentiananae). The following families are included according to the

APG III system The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy being developed by the Angiosperm Phylogeny Group (APG). Published in 2009, it was superseded in 2016 by a fu ...

: * Family

Apocynaceae Apocynaceae (from '' Apocynum'', Greek for "dog-away") is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines, commonly known as the dogbane family, because some taxa were used as dog poison Members ...

(424 genera) * Family Gelsemiaceae (2 genera) * Family

Gentianaceae Gentianaceae is a family of flowering plants of 103 genera and about 1600 species. Etymology The family takes its name from the genus ''Gentiana'', named after the Illyrian king Gentius. Distribution Distribution is cosmopolitan. Characteristi ...

(87 genera) * Family

Loganiaceae The Loganiaceae are a family of flowering plants classified in order Gentianales. The family includes up to 13 genera, distributed around the world's tropics. There are not any great morphological characteristics to distinguish these taxa from ot ...

(13 genera) * Family

(611 genera)

Phylogeny

The following

phylogenetic tree A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...

is based on

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

studies of

DNA sequence DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. T ...

Etymology

It takes its name from the family

, which in turn is based on the name of the type genus, ''

Gentiana ''Gentiana'' is a genus of flowering plants belonging to the gentian family (Gentianaceae), the tribe Gentianeae, and the monophyletic subtribe Gentianinae. With about 400 species it is considered a large genus. They are notable for their m ...

''. The genus name is a tribute to

Gentius Gentius ( grc, Γένθιος, "Génthios"; 181168 BC) was an Illyrian king who belonged to the Labeatan dynasty. He ruled in 181–168 BC, being the last attested Illyrian king. He was the son of Pleuratus III, a king who kept positive relati ...

, an Illyrian king.

Characteristics

This large order has a variety of different plants, ranging from small

herbaceous plants Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of ...

and saprophytes to

shrubs A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

and large

trees In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are u ...

.Struwe, Lena. (2002). Gentianales (Coffees, Dogbanes, Gentians and Milkweeds)
10.1038/npg.els.0003732
Species are, however, united by their simple and opposite leaves and typically have showy pentamerous flowers (flowers in which components occur in multiples of five) and show nuclear endosperm formation (in which cell division takes place without the cell wall forming between divisions). Many species have structures between the leaf petioles, such as ridges or

stipules In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...

. Many species also have colleters; thick hair-like structures that secrete

mucilage Mucilage is a thick, gluey substance produced by nearly all plants and some microorganisms. These microorganisms include protists which use it for their locomotion. The direction of their movement is always opposite to that of the secretion of m ...

, a thick gluey substance.

Distribution

Species of this order are found in moist climates around the world. They are most common in tropical regions.

Uses

Many gentianales contain toxic compounds and species have a variety of uses. Some species are also grown ornamentally. Well-known members of Gentianales are

coffee Coffee is a drink prepared from roasted coffee beans. Darkly colored, bitter, and slightly acidic, coffee has a stimulating effect on humans, primarily due to its caffeine content. It is the most popular hot drink in the world. Seeds of ...

frangipani ''Plumeria'' (), known as frangipani, is a genus of flowering plants in the subfamily Rauvolfioideae, of the family Apocynaceae. Most species are deciduous shrubs or small trees. The species variously are endemic to Mexico, Central America, and ...

, ''

Gardenia ''Gardenia'' is a genus of flowering plants in the coffee family, Rubiaceae, native to the tropical and subtropical regions of Africa, Asia, Madagascar and Pacific Islands, and Australia. The genus was named by Carl Linnaeus and John Ellis af ...

'',

gentian ''Gentiana'' is a genus of flowering plants belonging to the gentian family (Gentianaceae), the tribe Gentianeae, and the monophyletic subtribe Gentianinae. With about 400 species it is considered a large genus. They are notable for their mostl ...

oleander ''Nerium oleander'' ( ), most commonly known as oleander or nerium, is a shrub or small tree cultivated worldwide in temperate and subtropical areas as an ornamental and landscaping plant. It is the only species currently classified in the ge ...

, and periwinkle. Some Gentianales species have been used in traditional medicine in rural southeastern Asia countries. ''

Gelsemium sempervirens ''Gelsemium sempervirens'' is a twining vine in the family Gelsemiaceae, native to subtropical and tropical America: Honduras, Guatemala, Belize, Mexico (Chiapas, Oaxaca, Veracruz, Puebla, Hidalgo),Gelsemium elegans'' has been used in rheumatoid arthritis pain, neuropathic pain, skin ulcers, and even cancers. The compounds found in some species are used in the synthesis of modern medicines. Cinchona trees, for example, are a source of quinine, which is used to treat malaria.

Vinblastine Vinblastine (VBL), sold under the brand name Velban among others, is a chemotherapy medication, typically used with other medications, to treat a number of types of cancer. This includes Hodgkin's lymphoma, non-small cell lung cancer, bladder ca ...

, which has anti-tumor properties as it disrupts cell division, is used in

chemotherapy Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs (chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemother ...

. It is extracted from the

Madagascar periwinkle ''Catharanthus roseus'', commonly known as bright eyes, Cape periwinkle, graveyard plant, Madagascar periwinkle, old maid, pink periwinkle, rose periwinkle, is a species of flowering plant in the family Apocynaceae. It is native and endemic to M ...

References

Angiosperm orders {{Gentianales-stub