Dierama

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Dierama
Dierama igneum1UME.jpg
Dierama igneum
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Asparagales
Family: Iridaceae
Subfamily: Ixioideae
Tribe: Ixieae
Genus: Dierama
K. Koch
Type species
Dierama ensifolium
Koch & Bouché
Species

See text

Dierama is a genus of flowering plants in the iris family, Iridaceae. Common names include harebells, fairybells, and wandflowers in English and grasklokkies in Afrikaans.[1] They are native to Africa, with most occurring in the southern regions of the continent.[2] The center of diversity is the Province of KwaZulu-Natal in eastern South Africa.[1]

Description[edit]

Plants of this genus are evergreen perennial herbs growing from large, fibrous-coated corms. The lowest two or three leaves are cataphylls that sheath the lower stem and may soon become dry. The thin, wiry, branching stem may bend and droop when in flower. It is lined with leaves that have linear blades with thick longitudinal veins and often no midrib. The inflorescence is a panicle of several spikes of flowers. The spikes may hang like bells or grow erect. The bracts around the flowers are usually dry, thin, membranous, translucent, and streaked or veined with brown. The bell-shaped flowers of most wild species are pink, and there are also red, purple, yellow, and white taxa.[2] There are many cultivars in a range of colors, sometimes with spots of yellow or blue.[3] The fruit is a spherical capsule.[2]

Etymology[edit]

The genus name is derived from the Greek word dierama, meaning "funnel", and alludes to the shape of the flower.[4]

Diversity[edit]

There are about 44 species.[2]

Species include:[5][6]

Uses[edit]

Some dieramas are cultivated as ornamental plants, such as the purple-pink-flowered D. pendulum.[12] The South African endemic D. erectum is grown for the large, pink flowers it bears on tall, erect stems. It is prone to attack by the bean weevil Urodon lilii.[14]

Certain species have been used in traditional African medicine and spiritual practices. D. erectum is used as an enema by the Sotho people and as a treatment for stomach problems. The corm of the plant is a fertility charm for bringing a good harvest.[14]

Conservation[edit]

Some species, especially the narrow endemics, are decreasing in abundance due to loss of habitat. The South African natives D. ambiguum, D. erectum, and D. nixonianum are considered endangered species.[6]

References[edit]

  1. ^ a b Glen, H. Dierama reynoldsii. South African National Biodiversity Institute. 2005.
  2. ^ a b c d Dierama K.Koch. Flora Zambesiaca. Royal Botanic Gardens, Kew.
  3. ^ Hilliard, O. M. and B. L. Burtt. (1991). Dierama: the Hairbells of Africa. Randburg: : Acorn Books. ISBN 1-874802-01-7. 
  4. ^ Manning, J. and P. Goldblatt. (2008). The Iris Family: Natural History & Classification. Portland, Oregon: Timber Press. pp. 91–93. ISBN 0-88192-897-6. 
  5. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al Arnold, T. H. and B. C. de Wet, Eds. Plants of Southern Africa: Names & Distribution. In: Memoirs of the Botanical Survey of South Africa No. 62. National Botanical Institute, South Africa. 1993. ISBN 1-874907-03-X
  6. ^ a b Dierama. Red List of South African Plants. South African National Biodiversity Institute.
  7. ^ Dierama cupuliflorum. World Checklist of Selected Plant Families. Kew.
  8. ^ Dierama densiflorum. World Checklist of Selected Plant Families. Kew.
  9. ^ Dierama inyangense. World Checklist of Selected Plant Families. Kew.
  10. ^ Dierama longistylum. Flora Zambesiaca. Royal Botanic Gardens, Kew.
  11. ^ Dierama parviflorum. Flora Zambesiaca. Royal Botanic Gardens, Kew.
  12. ^ a b Dierama pendulum. Missouri Botanical Garden.
  13. ^ Dierama plowesii. World Checklist of Selected Plant Families. Kew.
  14. ^ a b Koetle, M. J., et al. (2010). In vitro regeneration in Dierama erectum Hilliard. Plant Cell, Tissue and Organ Culture 103(1) 23-31.