Gentianales is an order 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 th ...

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 dicots ...

. 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 Gentianiflorae (also called Gentiananae). The following families are included according to the APG III system: * 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 of ...

(424 genera) * Family

Gelsemiaceae Gelsemiaceae is a family of flowering plants, belonging to the order Gentianales. The family contains only three genera: '' Gelsemium'', '' Mostuea'' and '' Pteleocarpa''. ''Gelsemium'' has three species, one native to Southeast Asia and southern ...

(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. Characteri ...

(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 is based on molecular phylogenetic studies of DNA sequences.

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 most ...

''. 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 t ...

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. 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'',

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 ''Gelsemium elegans'', commonly known as heartbreak grass, is a poisonous plant of the family Gelsemiaceae found in China and other Asian countries. It contains toxic alkaloids such as gelsemine, gelsenicine, gelsevirine and koumine. Crumbled ...

'' 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. Chemothe ...

. 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