''Rheum rhaponticum'', the false rhubarb, rhapontic rhubarb or rhapontic, is a plant species in the genus '' Rheum'' found in the wild. It is the only ''Rheum'' species found only in Europe, and is now restricted to the

Rila Rila ( bg, Рила, ) is the highest mountain range of Bulgaria, the Balkan Peninsula and Southeast Europe. It is situated in southwestern Bulgaria and forms part of the Rila– Rhodope Massif. The highest summit is Musala at an elevation of 2, ...

mountain range in south-western

Bulgaria Bulgaria (; bg, България, Bǎlgariya), officially the Republic of Bulgaria,, ) is a country in Southeast Europe. It is situated on the eastern flank of the Balkans, and is bordered by Romania to the north, Serbia and North Macedo ...

. It was introduced to other countries in Europe. It is considered to be one of the parents of the modern culinary

rhubarb Rhubarb is the fleshy, edible stalks ( petioles) of species and hybrids (culinary rhubarb) of '' Rheum'' in the family Polygonaceae, which are cooked and used for food. The whole plant – a herbaceous perennial growing from short, thick rhi ...

Description

''Rheum rhaponticum'' is a robust

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also widel ...

herbaceous plant 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 ...

growing from a woody

rhizome In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow ...

. It has large, undivided leaves, with succulent petioles (stalks). The blade of the leaf is up to 50 cm long, and is wider than its length. The leaves are heart-shaped at the base with five prominent nerves. The petioles are concave above and convex below, with about 10 ridges. The flowers are borne in a

panicle A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are of ...

and are light greenish-yellow in colour. The fruits have membrane-like wings and are about 5 mm long on

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...

(stems) of the same length.

Karyotypy

In 1928, Jaretzky found ''R. rhaponticum'' to have 2''n'' = 44

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins ar ...

s, however, a study of the wild Bulgarian population in 1989 revealed a chromosome number of 2''n'' = 22.

Taxonomy

''Rheum rhaponticum'' was first described by

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, ...

in 1753. Linnaeus knew the plant only from cultivated specimens grown at

Uppsala Uppsala (, or all ending in , ; archaically spelled ''Upsala'') is the county seat of Uppsala County and the fourth-largest city in Sweden, after Stockholm, Gothenburg, and Malmö. It had 177,074 inhabitants in 2019. Located north of the ca ...

in Sweden and in the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

. These were derived from plants grown the early 17th century in the Padua botanic garden, collected by a former student of the botanic garden, Francisco Crasso, in what was then known as Thrace. Plants from the Rila mountain range have been compared to those in Linnaeus's herbarium and are considered to be the same species. The name ''Rheum rhaponticum'' has also been applied in a broad sense to culinary rhubarb.

History

The word ''rha ponticum'',

Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...

for 'rha from Pontus' (Pontus corresponds to the northern coast of

Anatolia Anatolia, tr, Anadolu Yarımadası), and the Anatolian plateau, also known as Asia Minor, is a large peninsula in Western Asia and the westernmost protrusion of the Asian continent. It constitutes the major part of modern-day Turkey. The re ...

), was first mentioned by

Dioscorides Pedanius Dioscorides ( grc-gre, Πεδάνιος Διοσκουρίδης, ; 40–90 AD), “the father of pharmacognosy”, was a Greek physician, pharmacologist, botanist, and author of '' De materia medica'' (, On Medical Material) —a 5-vo ...

, who says that this is the name the Romans used for a valued medicinal root imported from the east. Dioscorides also mentions the root is most similar to that of ''

Centaurea ''Centaurea'' () is a genus of over 700 species of herbaceous thistle-like flowering plants in the family Asteraceae. Members of the genus are found only north of the equator, mostly in the Eastern Hemisphere; the Middle East and surrounding reg ...

''. Throughout most of the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire ...

and early modern era Europeans were unaware of the source for these roots, which had become known as ''rheum barbarum'' (among many other names, including the Persian ''raved''). Botanists such as

Leonhart Fuchs Leonhart Fuchs (; 17 January 1501 – 10 May 1566), sometimes spelled Leonhard Fuchs and cited in Latin as ''Leonhartus Fuchsius'', was a German physician and botanist. His chief notability is as the author of a large book about plants and th ...

(in 1542) and

Rembert Dodoens Rembert Dodoens (born Rembert Van Joenckema, 29 June 1517 – 10 March 1585) was a Flemish physician and botanist, also known under his Latinized name Rembertus Dodonaeus. He has been called the father of botany. Life Dodoens was born Rember ...

(in 1554) identified a species of thistle in the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae ...

, ''

Rhaponticum scariosum ''Rhaponticum scariosum'', common name Giant Scabiosa, is a perennial herbaceous flowering plant of the genus ''Rhaponticum'' of the family Asteraceae. Description The biological form of ''Rhaponticum scariosum'' is '' hemicryptophyte'' '' scapo ...

'', as the source of the root, thus this plant was used to produce an inferior rhubarb. ''R. rhaponticum'' was the first rhubarb plant ever to be seen by Europeans, but it took some time before Europeans accepted that rhubarb was harvested from '' Rheum''.

Chemistry

Hyperoside Hyperoside is a chemical compound. It is the 3-''O''- galactoside of quercetin. Natural occurrences Hyperoside has been isolated from ''Drosera rotundifolia'', from the Lamiaceae ''Stachys sp.'' and ''Prunella vulgaris'', from ''Rumex acetosell ...

, the 3-O-galactoside of quercetin, can be found in ''R. rhaponticum'', where it may serve as a UV blocker found in the bracts. It also contains the hydroxystilbenes rhaponticin and desoxyrhaponticin.

References

External links

* * {{Authority control rhaponticum Plants described in 1753 Taxa named by Carl Linnaeus Endemic flora of Bulgaria