Tradescantia

Tradescantia
Tradescantia virginiana
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
(unranked): Commelinids
Order: Commelinales
Family: Commelinaceae
Subfamily: Commelinoideae
Tribe: Tradescantieae
Subtribe: Tradescantiinae
Genus: Tradescantia
Ruppius ex L.[1][2]
Type species
Tradescantia virginiana
L.
Sections
Synonyms[2][3]

Tradescantia /ˌtrædˈskæntiə/,[4] the spiderworts,[5] is a genus of 75 species of herbaceous perennial plants in the family Commelinaceae, native to the New World from southern Canada south to northern Argentina including the West Indies. They were introduced into Europe as ornamental plants in the seventeenth century and are now grown as such in many parts of the world. Subsequently some species have become naturalized in various regions of Europe, Asia, Africa, Australia and assorted oceanic islands.[3]

Tradescantia are weakly upright to scrambling plants, growing to 30–60 cm tall (0.98–1.97 ft), and are commonly found individually or in clumps in wooded areas and fields. A number of the species flower in the morning and when the sun shines on the flowers in the afternoon they close, but can remain open on cloudy days until evening. The three species of Wandering Jew, one native to eastern Mexico, also belong to the Tradescantia genus. Other names used for various species include spider-lily, cradle-lily, oyster-plant and flowering inch plant.

The genus is of interest to cytogenetics because of the evolutionary changes in the structure and number of their chromosomes. In addition to their use as ornamentals, the genus is of economic importance because a number of species have become pests to cultivated crops. They have also been used as bioindicators for the detection of environmental mutagens.

Description

Tradescantia are herbaceous perennials and include both climbing and trailing species, reaching 30–60 centimetres (0.98–1.97 ft) in height. The leaves are long, thin and blade-like to lanceolate, from 3–45 cm long (1.2–17.7 in). The flowers can be white, pink, or purple, but are most commonly bright blue, with three petals and six yellow anthers. The sap is mucilaginous and clear.

Taxonomy

Evolution and genetics

The effect on chiasma (pl. chiasmata) frequency of the irradiation of different premeiotic and early meiotic stages was investigated in Tradescantia paludosa.[6] A chiasma is a cytologically visible interchange at corresponding points between homologous chromosomes. It is the basis for crossover recombination during meiosis. Chiasma frequency was found to increase following irradiation of the late zygotene early pachytene stages of meiosis. This finding may reflect increased homologous recombinational DNA repair in response to increased radiation-induced DNA damage.[7]

Subdivision

Tradescantia fluminensis
(Austrotradescantia )
Tradescantia guatemalensis
(Coholomia)
Tradescantia brevifolia
(Setcreasea)
Tradescantia occidentalis
(Tradescantia: Virginianeae)
Tradescantia sillamontana
(Tradescantia: Sillamontanae)

In the 1980s David Hunt divided the genus into 8[8] (later 12)[9] sections, with the nominate section (Tradescantia) further subdivided into a further four series, this superseded an earlier system by Clarke (1881).[10] Hunt originally recognised 60 species of which over half (32) he placed in section Tradescantia. Hunt's original speciation is given here, as further circumscribed by Burns et al. (2011).[11] Enlarging the sections from eight to twelve added six further species (total 68). Within section Tradescantia he distinguished the American species (series Virginianae) from the three Mexican series (Tuberosae, Sillamontanae, Orchidophyllae). 'Type' here indicates Species typica. Numbering of sections refers to Hunt's original (1980) system as a cross check to his index. The renumbered sections from 1986 are given in italics, e.g. (1)(5).
Note 1: The place of T. schippii is uncertain. Hunt indicates it is included in section Zebrina, but Burns considers the section monotypic
Note 2: T. blossfeldiana as used by Hunt and Burns is now considered a synonym for T. cerinthoides. Hunt originally listed these as separate species. Hunt also listed T. potosina and T. nuevoleonensis as separate species, but the latter is now the accepted name, while T. subramosa and T. subtilis are now considered synonyms for T. maysillesii rather than separate species.[12]

Section Austrotradescantia (3)(7) D.R.Hunt. 5 species

(Brazil, Uruguay, N Argentina)

  • Tradescantia anagallidea Seub.
  • Tradescantia umbraculifera Hand.-Mazz.
  • Tradescantia cerinthoides Kunth syn. T blossfeldiana
  • Tradescantia crassula Link & Otto Succulent spiderwort
  • Tradescantia fluminensis Vell. Small-leaf spiderwort type
Section Campelia (1) (Rich.) D. R. Hunt 1 species

(Tropical America)

  • Tradescantia zanonia (L.) Sw. Cojite Blanco Type
Section Coholomia (2)(6) D.R.Hunt 1 species

(Guatemala, El Salvador, S Mexico)

  • Tradescantia guatemalensis C. B. Clarke ex Donn.Sm. Type
Section Corinna (2) D.R.Hunt 1 species

(S Mexico, Guatemala, Nicaragua and Costa Rica)

  • Tradescantia soconuscana Matuda Type
Section Cymbispatha (1)(5) (Pichon) D.R.Hunt 9 species

(Mexico to Bolivia and Brazil)

  • Tradescantia commelinoides Schult.f. Type
  • Tradescantia coscomatepecana Matuda
  • Tradescantia cymbispatha C.B.Clarke
  • Tradescantia deficiens Brandegee
  • Tradescantia gracillima Standl.
  • Tradescantia plusiantha Standl.
  • Tradescantia standleyi Steyermark
  • Tradescantia tonalamonticola Matuda
  • Tradescantia venezuelensis Steyermark
Section Mandonia (7)(11) D.R.Hunt 7 species

(Mexico: Durango)

  • Tradescantia ambigua Mart. Type
  • Tradescantia burchii D.R.Hunt
  • Tradescantia crassifolia Cav. Leatherleaf spiderwort
  • Tradescantia llamasii Matuda
  • Tradescantia peninsularis Brandegee
  • Tradescantia tepoxtlana Matuda
  • Tradescantia velutina Kunth & Bouché
Section Parasetcreasea (8)(12) D.R.Hunt 1 species

(Mexico: Chihuahua to Oaxaca)

  • Tradescantia andrieuxii C.B.Clarke Type
Section Rhoeo (4) (Hance) D.R.Hunt 1 species

(Mexico (Yucatán), Belize)

Section Separotheca (6)(10) (Waterfall) D.R.Hunt 1 species

(Mexico: Durango)

  • Tradescantia pygmaea D.R.Hunt Type
Section Setcreasea (5)(9) (K.Schum. & Sydow) D.R.Hunt 5 species

(U.S.A.: Texas; Mexico: Chihuahua to Veracruz)

  • Tradescantia brevifolia (Torr.) Rose. Trans-Pecos spiderwort type
  • Tradescantia buckleyi (I.M.Johnst.) D.R.Hunt Buckley's spiderwort
  • Tradescantia hirta D.R.Hunt
  • Tradescantia leiandra Torr. Canyon spiderwort
  • Tradescantia pallida (Rose) D.R.Hunt Purple queen
Section Tradescantia (4)(8) L. 32 species
  • Series Virginianae (I) D.R.Hunt (18 species)
  • (U.S.A.)
    • Tradescantia bracteata Small Bracted spiderwort
    • Tradescantia canaliculata Raf.
    • Tradescantia edwardsiana Tharp Plateau spiderwort
    • Tradescantia ernestiana Anderson & Woodson Ernest's spiderwort
    • Tradescantia gigantea Rose Giant spiderwort
    • Tradescantia hirsuticaulis Small Hairystem spiderwort
    • Tradescantia hirsutiflora Bush Hairyflower spiderwort
    • Tradescantia humilis Rose Texas spiderwort
    • Tradescantia longipes E.S.Anderson & Woodson Wild crocus
    • Tradescantia occidentalis (Britton) Smyth Prairie spiderwort
    • Tradescantia ohiensis Raf. Ohio spiderwort
    • Tradescantia ozarkana E.S.Anderson & Woodson Ozark spiderwort
    • Tradescantia paludosa E.S.Anderson & Woodson Confederate spiderwort
    • Tradescantia reverchonii Bush Reverchon's spiderwort
    • Tradescantia roseolens Small Longleaf spiderwort
    • Tradescantia subacaulis Bush Stemless spiderwort
    • Tradescantia subaspera Ker Gawl. Zigzag spiderwort
    • Tradescantia tharpii E.S.Anderson & Woodson Tharp's spiderwort
    • Tradescantia virginiana L. Virginia spiderwort type
  • Series Sillamontanae (II) D.R.Hunt (2 species)
  • (NE Central Mexico)
  • Series Tuberosae (III) D.R.Hunt (10 species)
  • (U.S.A.: Texas; Mexico: Chihuahua to Puebla)
    • Tradescantia cirrifera Mart.
    • Tradescantia maysillesii Matuda syn. T. subramosa, T. subtilis
    • Tradescantia monosperma Brandegee
    • Tradescantia nuevoleonensis Matuda syn. T. potosina
    • Tradescantia pinetorum Greene Pinewoods spiderwort type
    • Tradescantia wrightii Rose & Bush Wright's spiderwort
  • Series Orchidophyllae (IV) D.R.Hunt (2 species)
  • (Mexico: Colima to Guerrero)
    • Tradescantia mirandae Matuda
    • Tradescantia orchidophylla Rose & Hemsl. ex Hemsl. Type
Section Zebrina (3) (Schnizlein) D.R.Hunt. 1 species

(Mexico to Venezuela)
(*Tradescantia schippii D.R.Hunt.)

Incertae sedis
  • Tradescantia pedicellata Celarier Edwards Plateau spiderwort[8][9][13][14]

Nothospecies

Tradescantia × andersoniana

Formerly placed here

Species

By 1998 Fadden listed 70 species,[17] while currently The Plant List accepts 75.[18]

Etymology

The name of the genus by Linnaeus honours the English naturalists and explorers John Tradescant the Elder (ca. 1570s – 1638) and John Tradescant the Younger (1608–1662).[19][20] They introduced many new plants to English gardens. Tradescant the Younger mounted three expeditions to the New World colony of Virginia.[21] From there Tradescantia virginiana, the type species, was brought to England in 1629.

The genus Tradescantia has received many common names, varying by region and country. Some of these names refer to the plants' great dispersal ability or invasiveness, such as "Wandering Jew". The latter refers to a Christian myth of the Wandering Jew, condemned to wander the earth for taunting Jesus on the way to his crucifixion.[22] In Spanish, it is sometimes referred to as "flor de Santa Lucía" (Saint Lucy's flower), in reference to the Saint's reputation as the patron saint of sight, and the use of the juice of the plant as eye drops to relieve congestion.[23]

Distribution and habitat

The first species described, Virginia Spiderwort T. virginiana, is native to the eastern United States from Maine to Alabama, and Canada in southern Ontario. Virginia Spiderwort was introduced to Europe in 1629, where it is cultivated as a garden flower.

Conservation

The Western Spiderwort T. occidentalis is listed as an endangered species in Canada, where the northernmost populations of the species are found at a few sites in southern Saskatchewan, Manitoba and Alberta; it is however more common further south in the United States south to Texas and Arizona.

Cultivation

Though sometimes considered a weed, spiderwort is cultivated for borders and also used in containers. Where it appears as a volunteer, it is often welcomed and allowed to stay. Temperate species are grown as garden plants while tropical species such as T. zebrina and T. spathacea are used for house plants.[20]

A common cultivar group responsible for most commercially available plants is derived from the naturally occurring interspecific hybrid (nothospecies) Tradescantia × andersoniana, an invalid name more correctly referred to as 'Andersoniana Group' since it includes several cultivars, the origins of which are complex.[24] The group were derived from naturally occurring cross-pollination between Tradescantia virginiana, T. ohiensis, and T. subaspera in overlapping ranges within continental North America.[20] They share a number of characteristics, although differing in flower colour.[25] The cultivars in this group include 'Blue Stone', 'Isis', 'Innocence', 'Snowcap', 'Osprey', 'Iris Pritchard', 'Pauline', 'Red Cloud' and 'Karminglut' ('Carmine Glow').[26][20] Tradescantia × andersoniana var. caerulea plena is a double flowered variety with dark blue flowers.[24][25]

Toxicity

Some members of the genus Tradescantia may cause allergic reactions in pets (especially cats and dogs), characterised by red, itchy skin. Notable culprits include T. albiflora (Scurvy Weed); T. spathacea (Moses In The Cradle); and T. pallida (Purple Heart).

Uses

Hoverfly at Tradescantia flower; note the blue stamen hairs

The American Indians used T. virginiana to treat a number of conditions, including stomach ache and cancer. it was also used as a food source.[20] The cells of the stamen hairs of some Tradescantia are colored blue, but when exposed to sources of ionizing radiation such as gamma rays, the cells mutate and change color to pink; they are one of the few tissues known to serve as an effective bioassay for ambient radiation levels.[27][20]

References

  1. Linnaeus Sp. Pl.: 288 (1753).
  2. 1 2 "Genus: Tradescantia L.". Germplasm Resources Information Network. United States Department of Agriculture. 2004-08-10. Retrieved 2011-03-20.
  3. 1 2 Kew World Checklist of Selected Plant Families
  4. Sunset Western Garden Book, 1995:606–607
  5. "Tradescantia". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 14 December 2015.
  6. Lawrence, C.W. (1961). "The effect of radiation on chiasma formation in Tradescantia". Radiation Botany 1: 92–96. doi:10.1016/s0033-7560(61)80011-2.
  7. Bernstein H and Bernstein C (2013). Evolutionary Origin and Adaptive Function of Meiosis. In Meiosis: Bernstein C and Bernstein H, editors. ISBN 978-953-51-1197-9, InTech, http://www.intechopen.com/books/meiosis/evolutionary-origin-and-adaptive-function-of-meiosis
  8. 1 2 Hunt, David R. (1980). "Sections and Series in Tradescantia: American Commelinaceae: IX". Kew Bulletin 35 (2): 437–442. doi:10.2307/4114596. JSTOR 4114596.
  9. 1 2 Hunt, David R. (1986). "Campelia, Rhoeo and Zebrina united with Tradescantia: American Commelinaceae: XIII". Kew Bulletin 41 (2): 401–405. doi:10.2307/4102948. JSTOR 4102948.
  10. C B Clarke Commelinaceae. In A. & C. De Candolle Monogr. Phan. 3: 288, 113-324 (1881).
  11. 1 2 Burns, Jean H.; Faden, Robert B.; Steppan, Scott J. (2011). "Phylogenetic Studies in the Commelinaceae Subfamily Commelinoideae Inferred from Nuclear Ribosomal and Chloroplast DNA Sequences". Systematic Botany 36 (2): 268–276. doi:10.1600/036364411X569471.
  12. World Checklist of Selected Plant Families
  13. "Tradescantia". Integrated Taxonomic Information System. Retrieved 2011-06-16.
  14. 1 2 "GRIN Species Records of Tradescantia". Germplasm Resources Information Network. United States Department of Agriculture. Retrieved 2011-06-16.
  15. Feddes Repert. Spec. Nov. Regni Veg. 56: 282 (1954)
  16. World Checklist
  17. Faden, R. B. (1998-01-01). Kubitzki, Professor Dr Klaus, ed. Commelinaceae. The Families and Genera of Vascular Plants. Springer Berlin Heidelberg. pp. 109–128. doi:10.1007/978-3-662-03531-3_12. ISBN 978-3-642-08378-5.
  18. The Plant List
  19. Quattrocchi, Umberto (2000). CRC World Dictionary of Plant Names: Common Names, Scientific Names, Eponyms, Synonyms, and Etymology. IV R-Z. Taylor & Francis US. p. 2697. ISBN 978-0-8493-2678-3.
  20. 1 2 3 4 5 6 Hawke 2010.
  21. José Manuel Sánchez de Lorenzo-Cáceres. Las especies del género Tradescantia cultivadas en España. 2004.
  22. Anderson, George K. The Legend of the Wandering Jew. Providence: Brown University Press, 1965. xi, 489 p.; ISBN 0-87451-547-5
  23. Bugatti, C.L. 2008. Desde el jardín. Esos yuyos con aire lujoso. La Nación (Argentina).
  24. 1 2 Dave's Garden 2015, Tod Boland. Spiderwort Hybrids - Tradescantia X andersoniana. September 1, 2012.
  25. 1 2 Christman 2005.
  26. Dave's Garden 2015, Spiderwort, Virginia Spiderwort, Lady's Tears Tradescantia x andersoniana 'Karminglut'.
  27. Ichikawa, Sadao (1972). "Somatic Mutatiion Rate in Tradescantia Stamen Hairs at Low Radiation Levels: Finding of Low Doubling Doses of Mutations". The Japanese Journal of Genetics 47 (6): 411–421. doi:10.1266/jjg.47.411.

Bibliography

Gallery

External links

Wikisource has the text of the 1920 Encyclopedia Americana article Spiderwort.
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Look up tradescantia in Wiktionary, the free dictionary.
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