Nerine

This article is about the plant genus. For the anime character, see Nerine (Shuffle!).
Nerine
Nerine bowdenii
Scientific classification
Kingdom: Plantae
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Amaryllidaceae
Subfamily: Amaryllidoideae
Genus: Nerine
Herb., nom. cons.
Species

See text.

Synonyms[1]

Nerine /nᵻˈraɪniː/[2] is a genus of flowering plants belonging to the Amaryllidaceae family, subfamily Amaryllidoideae.[3] They are bulbous perennials, some evergreen, associated with rocky and arid habitats. They bear spherical umbels of lily-like flowers in shades from white through pink to crimson. In the case of deciduous species, the flowers may appear on naked stems before the leaves develop.[4] Native to South Africa,[5][6] there are about 30 species in the genus. Though described as lilies, they are not significantly related to the true lilies Lilium,[4] but more closely resemble their relatives, Amaryllis and Lycoris. The genus was established by the cleric and Amaryllidaceae specialist William Herbert in 1820.[7]

Nerines have been widely cultivated and much hybridized worldwide, especially Nerine bowdenii, N. sarniensis and N. undulata (previously known as N. flexuosa). The hybrid cultivar 'Zeal Giant' has gained the Royal Horticultural Society's Award of Garden Merit.[8] The other 20 species are rarely cultivated and very little is known regarding their biology. Many species are threatened with extinction due to the loss or degradation of their habitat.[9]

Description

Nerine Inflorescence, leaves and Bulb.

Species of Nerine are herbaceous flowering plants that grow from bulbs. Their leaves are linear, obviously flat in some species and appearing threadlike in others. Their flowers are borne in an umbel on a solid leafless stem (scape). Individual flowers are either radially symmetrical (actinomorphic) or have one plane of symmetry (zygomorphic). Each flower has six narrow red or pink tepals joined at the base to form a short extended or recurved tube. The free parts of the tepals are generally wavy.

There are six stamens that are inserted in the base of the petals and frequently protrude from the flower. The stamens can be straight or curved with thin filaments and oblong anthers that attach to their filament at the back (dorsifixed). The inferior ovary has one to many ovules. The style is threadlike and has a three-lobed stigma. The fruit is a capsule.[10][11][12]

Inflorescence of Nerine bowdenii.
General aspect of Nerine sarniensis.
Many species of Nerine have petals with wavy edges, such as Nerine humilis shown in the image.
Profusion of flowers in Nerine filifolia, note the filiform leaves of this species.

Nerine species can be either evergreen or deciduous; the deciduous species can either grow during the winter or the summer. The growth cycle thus defines three groups. There is a strong association between a species' growth habit, the shape of its leaves and the amount of DNA in its cell nuclei. The largest group of 12 species contains the evergreen nerines that retain their leaves throughout the summer and winter (N. angustifolia, N. appendiculata, N. filamentosa, N. filifolia, N. frithii, N. gaberonensis, N. gibsonii, N. gracilis, N. masoniorum, N. pancratioides, N. platypetala and N. rehmannii). Their leaves are narrow and they have the smallest amount of DNA per nucleus (18.0–24.6 pg). Four deciduous species grow in the winter and do not have any leaves during the summer (N. humilis, N. pudica, N. ridleyi and N. sarniensis). They have wide leaves and more DNA per nucleus (25.3–26.2 pg). A final group of seven species only grow during the summer and have no leaves in the winter (N. bowdenii, N. duparquetiana, N. krigei, N. laticoma, N. marincowitzii, N. pusilla and N. undulata). They have wide leaves and the most DNA per nucleus (26.8–35.3 pg).[6][13]

Taxonomy

N. masoniorum, Osaka Prefectural Flower Garden, Japan

Nomenclature

The earliest published name for the genus was Imhofia, given by Lorenz Heister in 1755. The later name Nerine, published by William Herbert in 1820, was widely used, resulting in a decision to conserve the name Nerine and reject the name Imhofia.[1] The genus name derives from the Nereids (sea-nymphs) of Greek mythology that protected sailors and their ships.[14] When Herbert chose the name of these nymphs for the first species of the genus, Nerine sarniensis, he alluded to the story of how this South African species arrived on the island of Guernsey in the English Channel. It is said that a ship carrying boxes of the bulbs of this species destined for the Netherlands was shipwrecked on Guernsey. The boxes of bulbs were washed up on the island and the bulbs became established and multiplied around the coast.[7]

Classification and phylogeny

In the APG III system, the genus Nerine is placed in the subfamily Amaryllidoideae of a broadly defined family Amaryllidaceae. Within the subfamily, Nerine is placed in the tribe Amaryllideae. The phylogenetic relationships of the Amaryllideae have been investigated through molecular analysis of DNA combined with morphological data. This cladistic analysis has demonstrated that Nerine belongs to a monophyletic group together with Crossyne, Strumaria, Hessea, Namaquanula and Brunsvigia. The members of this clade all originate from South Africa and often have prostrate leaves, fused stamens forming a tube towards the base of the flower, dehiscent fruit, and seeds with a well developed seed coat and chlorophyll.[15]

Species

Species accepted by the World Checklist of Selected Plant Families as of February 2009 are:[16]

Hybrids

Nerine hybrids, along with the parent species, where known, are the following:[16]

Some Nerine species have been used to produce a hybrid with members of the genus Amaryllis, which are included in the hybrid genus (nothogenus) × Amarine. One of these hybrids is × Amarine tubergenii Sealy, which comes from a cross between Amaryllis belladonna and Nerine bowdenii.[16]

Conservation status

Some Nerine species from Eastern Cape Province are naturally rare, but they are not considered to be in immediate danger of extinction. These include the winter-growing species N. pudica that inhabits inaccessible locations in the Du Toitskloof and Sonderend mountains, and the summer-growing N. marincowitzii that originates from the semi-arid Karoo region.

A number of evergreen nerine species from areas of South Africa that have summer rain are in danger due to the loss or degradation of their habitat and at least two or three of them are on the verge of extinction. Nerine masonorum is probably the most critically threatened and it may even have become extinct as the area occupied by the only surviving colony has been used for the construction of housing.[17] Another species that is seriously threatened is N. gibsonii from Eastern Cape Province as the grasslands that it grows in have been seriously damaged by overgrazing and erosion resulting from the construction of paths and roads. In addition, this species rarely produces seeds as grazing cattle eat the flowers as soon as they appear.[18]

Various measures have been taken to relieve the threat of extinction from these species. One of these measures, thanks to their ease of cultivation, is the ex situ conservation of a number of populations of N. filamentosa, N. gibsonii, N. gracilis, N. huttoniae and N. masonorum in the Kirstenbosch botanical garden.[9] Another measure, this time relating to in situ cultivation is the official protection of some species in nature reserves, such as has happened for N. platypetala in the south of Mpumalanga.[19]

Cultivation and use

A number of the species of this genus are cultivated as ornamentals, such as Nerine sarniensis, Nerine undulata and Nerine bowdenii.[12] N. sarniensis is, probably, the best known species of the genus and it has been cultivated in Europe since the beginning of the 17th Century. N. bowdenii was introduced to England at the end of the 19th Century and used as an ornamental since the first decade of the 20th Century.[20] Along with Nerine bowdenii they have been extensively used in plant breeding programmes that have produced the majority of the commercially available hybrids.[11] The bulbs of Nerine species need a minimum of two years growth and development in order to produce their first flowers. The largest bulbs can give rise to two stems or more if they have been grown under suitable conditions. They are used as cut flowers as they can survive up to 14 days in a vase with water without showing any staining.[12]

References

  1. 1 2 "Nerine". Royal Botanic Gardens, Kew: World Checklist of Selected Plant Families. Retrieved 28 August 2009.
  2. ↑ Sunset Western Garden Book, 1995:606–607
  3. ↑ Stevens, P.F., Angiosperm Phylogeny Website: Asparagales: Amaryllidoideae
  4. 1 2 RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 1405332964.
  5. ↑ Duncan, G.D (2005). "Nerine pusilla". Curtis’s Botanical Magazine 22 (3): 169–175. doi:10.1111/j.1355-4905.2005.00485.x.
  6. 1 2 Zonneveld, B. J. M; G. D. Duncan. (2006). "Genome size for the species of Nerine Herb. (Amaryllidaceae) and its evident correlation with growth cycle, leaf width and other morphological characters.". Plant Systematics and Evolution 257 (4): 251–260. doi:10.1007/s00606-005-0381-x. Retrieved 23 March 2008.
  7. 1 2 Graham Duncan (2002). "Nerine sarniensis (L.) Herb.". Plants of South Africa. Kirstenbosch National Botanical Garden. Retrieved 5 August 2008.
  8. ↑ "RHS Plant Selector - Nerine 'Zeal Giant'". Retrieved 27 June 2013.
  9. 1 2 Duncan, D. (2008). "The distribution, habitat and conservation status of the species of Nerine" (PDF). Report of the Proceedings of a Hardy Nerine Study Day. RHS Herbaceous Plant Committee and the Nerine & Amaryllid Society. pp. 22–31. Retrieved 2 March 2009.
  10. ↑ Dimitri M. (1987). Enciclopedia Argentina de Agricultura y Jardinería. Tomo I. Descripción de plantas cultivadas. Buenos Aires: ACME S.A.C.I.
  11. 1 2 "Nerine". Gallery of The World Bulbs. International Bulb Society. Retrieved 28 April 2008.
  12. 1 2 3 Duncan, G.D. (2002). The genus Nerine. Bulbs 4(1): 9–15.
  13. ↑ Goldblatt P. 1972. Chromosome cytology in relation to classification in Nerine and Brunsvigia (Amaryllidaceae). J. S. African Bot. 38: 261-275.
  14. ↑ Coombes, Allen J. (2012). The A to Z of plant names. USA: Timber Press. p. 312. ISBN 9781604691962.
  15. ↑ Meerow, Alan W., Snijman, Deirdre A. 2001. Phylogeny of Amaryllidaceae tribe Amaryllideae based on nrDNA ITS sequences and morphology. Am. J. Bot. 88: 2321-2330.
  16. 1 2 3 "Royal Botanic Gardens, Kew: World Checklist Series". Retrieved 24 February 2009.
  17. ↑ Dold, T. (2000). The nerine from Misty Mount. Veld & Flora 86(4): 168–169.
  18. ↑ Dold, T. (2004). Nerine gibsonii. Veld & Flora 90(3): 102–104.
  19. ↑ Craib, C.L. (1996). Nerine platypetala: habitat studies and cultivation. Herbertia 51: 68–73.
  20. ↑ David, J. (2008). "The Nerine bowdenii story" (PDF). Report of the Proceedings of a Hardy Nerine Study Day. RHS Herbaceous Plant Committee and the Nerine & Amaryllid Society. pp. 31–41. Retrieved 2 March 2009.

Bibliography

External links

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