Agapanthus

''Agapanthus'' () is a genus of plants, the only one in the subfamily Agapanthoideae of the family Amaryllidaceae. The family is in the monocot order Asparagales. The name is derived .

Some species of ''Agapanthus'' are commonly known as lily of the Nile, or African lily in the UK. However, they are not lilies and all of the species are native to Southern Africa (South Africa, Lesotho, Eswatini, Mozambique), though some have become naturalized in scattered places around the world (Australia, Great Britain, Mexico, Ethiopia, Jamaica, etc.).Klaus Kubitzki. 1998. "" pages 58–60. In: Klaus Kubitzki (editor). 1998. ''The Families and Genera of Vascular Plants'' volume III. Springer-Verlag: Berlin;Heidelberg, Germany.

Species boundaries are not clear in the genus, and in spite of having been intensively studied, the number of species recognized by different authorities varies from 6 to 10. The type species for the genus is '' Agapanthus africanus''."Agapanthus" In: Index Nominum Genericorum. In: Regnum Vegetabile (see ''External links'' below). Many hybrids and cultivars have been produced. They are cultivated throughout warm areas of the world. They can especially be spotted throughout Northern California. Anthony Huxley, Mark Griffiths, and Margot Levy (1992). ''The New Royal Horticultural Society Dictionary of Gardening''. The Macmillan Press,Limited: London. The Stockton Press: New York. (set). Most of these were described in a book published in 2004.Wim Snoeijer. 2004. ''Agapanthus'' A revision of the genus. Timber Press: Portland, OR, USA. .

Description

''Agapanthus'' is a genus of herbaceous perennials that mostly bloom in summer. This leads to the Australian common name, Star of Bethlehem, as it blooms just before Christmas. The leaves are basal, curved, and linear, growing up to long. They are rather leathery and arranged in two opposite rows. The plant has a mostly underground stem called a rhizome (like a ginger 'root') that is used as a storage organ. The roots, which grow out of the rhizome, are white, thick and fleshy.

The inflorescence is a pseudo-umbel subtended by two large deciduous bracts at the apex of a long, erect scape, up to tall. They have funnel-shaped or tubular flowers, in hues of blue to purple, shading to white. Some hybrids and cultivars have colors not found in wild plants which includes bi-colored blue/lavender and white flowers flushed with pink as the blooms mature. The ovary is superior. The style is hollow. ''Agapanthus'' does not have the distinctive chemistry of Allioideae.

Taxonomy

The genus ''Agapanthus'' was established by Charles Louis L'Héritier de Brutelle in 1788.

Family placement

Which family the genus belongs to has been a matter of debate since its creation. In the Cronquist system, the genus was placed in a very broadly defined family Liliaceae, along with other lilioid monocots. In 1985, Dahlgren, Clifford, and Yeo placed ''Agapanthus'' in Alliaceae, close to '' Tulbaghia''.Rolf M.T. Dahlgren, H. Trevor Clifford, and Peter F. Yeo. 1985. ''The Families of the Monocotyledons''. Springer-Verlag: Berlin, Heidelberg, New York, Tokyo. . . Their version of Alliaceae also included several genera that would later be transferred to Themidaceae.

In 1996, following a phylogenetic analysis of DNA sequences of the gene ''rbcL'', Themidaceae was resurrected and ''Agapanthus'' was removed from Alliaceae.Michael F. Fay and Mark W. Chase. 1996. "Resurrection of Themidaceae for the ''Brodiaea'' alliance, and recircumscription of Alliaceae, Amaryllidaceae, and Agapanthoideae". ''Taxon'' 45(3):441–451. (see ''External links'' below). The authors found ''Agapanthus'' to be sister to Amaryllidaceae and transferred it to that family. This was not accepted by the Angiosperm Phylogeny Group when they published the original APG system in 1998, because the clade consisting of ''Agapanthus'' and Amaryllidaceae had only 63% bootstrap support. The APG system recognized three separate families, Agapanthaceae, Alliaceae sensu stricto, and Amaryllidaceae sensu stricto. Agapanthaceae consisted of ''Agapanthus'' only, and Dahlgren's idea that it is close to ''Tulbaghia'' was rejected.

When the APG II system was published in 2003, it offered the option of combining Agapanthaceae, Alliaceae sensu stricto, and Amaryllidaceae sensu stricto to form a larger family, Alliaceae sensu lato. When the name Amaryllidaceae was conserved by the ICBN for this larger family, its name was changed from Alliaceae to Amaryllidaceae, but its circumscription remained the same. When APG II was replaced by APG III in 2009, Agapanthaceae was no longer accepted, but was treated as subfamily Agapanthoideae of the larger version of Amaryllidaceae. Also in 2009, Armen Takhtajan recognized the three smaller families allowed by APG II, instead of combining them as in APG III.Armen L. Takhtajan (Takhtadzhian). ''Flowering Plants'' second edition (2009). Springer Science+Business Media. .

The table below summarizes the alternative family divisions:

Further molecular phylogenetic analyses of DNA sequences have confirmed that ''Agapanthus'' is sister to a clade consisting of subfamilies Allioideae and Amaryllidoideae of the family Amaryllidaceae (sensu APG III).J. Chris Pires, Ivan J. Maureira, Thomas J. Givnish, Kenneth J. Sytsma, Ole Seberg, Gitte Petersen, Jerrold I. Davis, Dennis W. Stevenson, Paula J. Rudall, Michael F. Fay, and Mark W. Chase. 2006. "Phylogeny, genome size, and chromosome evolution of Asparagales". ''Aliso'' 22(''Monocots: Comparative Biology and Evolution''):287–304. ISSN 0065-6275.

Species

Zonneveld and Duncan (2003) divided ''Agapanthus'' into six species (''A. africanus, A. campanulatus, A. caulescens, A. coddii, A. inapertus, A. praecox''). Four additional species had earlier been recognised by Leighton (1965) (''A. comptonii, A. dyeri, A. nutans'' and ''A. walshii''),Leighton, F. M. (1965). "The Genus ''Agapanthus'' L'Heritier". ''Journal of South African Botany'', supplementary volume IV. but were given subspecific rank by Zonneveld and Duncan. , the World Checklist of Selected Plant Families recognises seven species:

;formerly included
The name ''Agapanthus ensifolius'' was coined in 1799, referring to a species now called '' Lachenalia ensifolia.'' (see '' Lachenalia).''

Cultivation

''Agapanthus praecox'' can be grown within USDA plant hardiness zones 9 to 11. In lower-numbered zones, the rhizomes should be placed deeper in the soil and mulched well in the fall. Summer water should be provided. ''Agapanthus'' can be propagated by dividing clumps or by seeds. The seeds of most varieties are fertile.

Several hundred cultivars and hybrids are cultivated as garden and landscape plants. Several are winter-hardy to USDA Zone 7.

In the UK the following cultivars have received the Royal Horticultural Society's Award of Garden Merit:

*'Blue Ice' - pale blue
*'Blue Magic' - dark blue
* ('Rfdd') - white
* ('Mdb001') - white/purple
*'Happy Blue' - light blue
*'Hoyland Blue' - white/pale blue
*'Ice Blue Star' - pale blue-violet
*'Jacaranda' - blue/dark stripe
*'Jonny's White' - white
*'Leicester' - white
*'Loch Hope' - deep blue
*'Luly' - pale blue/violet
*'Marjorie' - pale violet-blue
*'Megan's Mauve' - lavender-blue
*'Midnight Star' - deep blue
*'Monique' - deep blue
*'Northern Star' - violet/deep blue
*'Purple Delight' - purple
*'Royal Blue' - bright blue
*'Sandringham' - bright blue
*'Sandy' - pale violet-blue
* ('Notfred') - blue
*'Sky' - sky blue
*'Summer Days' pale/dark blue

There are seven UK National Collection of ''Agapanthus'', held by:
* Ian Scroggy at Bali-Hai Nursery in Carnlough, County Antrim.
* Mike Grimshaw in Cam, Gloucestershire (cultivars bred and raised by Dick Fulcher).
* Mike Grimshaw in Cam, Gloucestershire (pre-2005 cultivars).
* Patrick Fairweather at Fairweather's Garden Centre in Beaulieu, Hampshire (cultivars from the Fairweather Nursery trials).
* Hoyland Plant Centre in Barnsley, Yorkshire (Hoyland hybrids, variegated, and special interest).
* Mrs Ruth Penrose at Bowdens Nursery in Sticklepath, Devon (Pine Cottage cultivars).
* Mr & Mrs R J & C L Fulcher in Eggesford, Devon (Pine Cottage cultivars).

Invasive species

In some regions, some agapanthus are listed as invasive species of plants. In New Zealand, '' Agapanthus praecox'' is classed as an "environmental weed" and calls to have it added to the National Pest Plant Accord have encountered opposition from gardeners.

Pests

As a rule, ''Agapanthus'' species are pest-hardy, neither being much attacked nor drastically affected by common garden pests. However, since the early 21st century ''Agapanthus'' in the far south of South Africa have fallen victim to a species of noctuid moth, the ''Agapanthus'' borer, '' Neuranethes spodopterodes''. The larvae of the moth bore into the budding inflorescence and as they mature they tunnel down towards the roots, or emerge from the stem and drop down to feed on the leaves or rhizomes. A severe attack promotes rot and may stunt or even kill the plant; even plants that survive commonly lose most of their inflorescences and fail to produce the desired show of flowers.

Though ''Neuranethes spodopterodes'' is invasive in the regions where it has emerged as a pest, it is not an exotic invader, but a translocated species, having been imported inadvertently from its natural range in more northerly regions of the country. In its original range, the moth is not of horticultural importance, being controlled by natural enemies that as yet have neither been identified nor imported along with the host plants. In contrast, the ''Agapanthus'' borer is of considerable concern in the South West, and its voracity is so impressive that the species shows promise as a possible control for invasive ''Agapanthus praecox'' in countries like New Zealand.

In 2016, a new species of gall midge, '' Enigmadiplosis agapanthi'', was described damaging Agapanthus in the United Kingdom.

Agapanthus begin bloom.JPG, Beginning to bloom
Agapanthus Prebloom.jpg, Pre-bloom stage
Bloemknop van een Agapanthus 'Senna'. 18-07-2023. (d.j.b) 02.jpg, Single pre-bloom bud
Agapanthus praecox Snow White. 03-08-2024 (d.j.b.).jpg, Flower buds of a ''Agapanthus praecox'' Snow White. A pure white dwarf, 45 cm.

Allergenic potential

''Agapanthus'' has low potential for causing allergies; its OPALS allergy scale rating is 2 out of 10.

It can cause itchy skin, burning sensation, as well as irritation if the sap from the leaves come in contact with skin

if ingested medical advise should be seeked immediately.

References

External links

''Agapanthus''
At
Index Nominum Genericorum
At:

At:



At

At: ttps://web.archive.org/web/20131030002020/http://www.plantsystematics.org/reveal/ Home page of James L. Reveal and C. Rose Broome

Original diagnosis of the genus by L'Héritier online at Project Gutenberg

Hoyland Plant Centre- UK National Collection Holders- Agapanthus



Wayback Machine

{{Authority control

Amaryllidaceae genera
Flora of Mozambique
Flora of Southern Africa
Taxa named by Charles Louis L'Héritier de Brutelle