Iochroma Explained

Iochroma is a genus of about 34 species of shrubs and small trees belonging to the nightshade family Solanaceae. Species are native from Mexico to south Brazil. They are found in the forests of Mexico and South America. Their hummingbird-pollinated flowers are tubular or trumpet-shaped, and may be blue, purple, red, yellow, or white, becoming pulpy berries. The cupular (cup-shaped) calyx is inflated in some species. The leaves are alternate, simple, and entire.[1] [2]

Iochromas are cultivated as flowering ornamentals and in cooler zones (zones 7–8/9) make useful patio shrubs for summer display or conservatory plants. The majority are not frost-hardy and must be overwintered under protection. In warmer zones (zones 9–10) they can be used as landscape plants.[3] They are commonly trained as standards (topiary) to control their size and shape. Iochroma flowers attract hummingbirds (Americas only) and bees to gardens.

Like many plants in the Solanaceae, Iochroma species contain phytochemicals with potential pharmaceutical value but the genus has not been exhaustively studied in this respect. Iochroma fuchsioides is taken by the medicine men of the Kamsa Indians of the Sibundoy valley in the Colombian Andes for difficult diagnoses, the unpleasant side effects lasting several days.[4] A variety of withanolides [5] and hydroxycinnamic acid amides [6] have been isolated from Iochroma species.

Taxonomy

The genus Iochroma was established by George Bentham in 1845.[7] Like other plant families, the Solanaceae is further divided into subfamilies, tribes and subtribes. Iochroma is in the subtribe Iochrominae along with the genera Dunalia, Eriolarynx, Saracha and Vassobia.[1] [2], Acnistus, previously treated as a separate genus, was regarded as a synonym of Iochroma.[7]

Species

The genus is currently divided into three sections., Plants of the World Online accepts the following species:[7]

Section Iochroma

Section Lehmannia

Section Spinosa

Unclassified

Former species

Species formerly placed in the genus Iochroma include:

Cultivation

Several forms of Iochroma (some wild collected, some garden hybrids) have been given cultivar names. Some of the cultivars have been assigned to species but others, mainly hybrids, have not. There may be some synonymy in this list.[10]

External links

(2008): Iochroma - an annotated list of the species and cultivars http://www.users.globalnet.co.uk/~drc/iochroma_home.htm

Notes and References

  1. Armando T. Hunziker: The Genera of Solanaceae. A.R.G. Gantner Verlag K.G., Ruggell, Liechtenstein 2001. pps. 220-226
  2. De Witt, S. and Baum, David A. 2006. Phylogenetics of the Florally Diverse Andean Clade Iochrominae (Solanaceae) American Journal of Botany 93(8): 1140–1153.
  3. Christopher Brickell (Ed.), The Royal Horticultural Society Encyclopedia of Garden Plants, pub. Dorking Kindersley 1996, pps. 554–555.
  4. Schultes, R. E. and Hoffman, A. (1992). Plants of the Gods. Their sacred, healing and hallucinogenic powers. Healing Arts Press, Rochester, Vermont. p. 46.
  5. Alfonso, D., Bernardinelli, G. and Kapetanidis, I. (1993). Withanolides from Iochroma coccineum. Phytochemistry 34 (2) : 517–521.
  6. Sattar, E. A., Glasl, H., Nahrstedt, A., Hilal, S. H., Zaki, A. Y. and El Zalabani, S. M. H. (1990). Hydroxycinnamic acid amides from Iochroma cyaneum. Phytochemistry 29 (12) : 3931–3933.
  7. Web site: Iochroma Benth.. . Plants of the World Online . Royal Botanic Gardens, Kew. 2023-02-07 .
  8. Web site: Iochroma australe Griseb.. . Plants of the World Online . Royal Botanic Gardens, Kew. 2023-02-07 .
  9. Web site: Iochroma cardenasianum Hunz.. . Plants of the World Online . Royal Botanic Gardens, Kew. 2023-02-07 .
  10. Shaw, J. M. H. (1998) "A Review of Iochroma in Cultivation". New Plantsman 5(3): 154–192.