Saintpaulia

Taxobox
name = "Saintpaulia"


image_width = 240px
image_caption = a "Saintpaulia ionantha" cultivar
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
ordo = Lamiales
familia = Gesneriaceae
genus = "Saintpaulia"
genus_authority = J.C.Wendl.
subdivision_ranks = Species
subdivision = "Saintpaulia inconspicua" "Saintpaulia goetzeana" "Saintpaulia ionantha" "Saintpaulia pusilla" "Saintpaulia shumensis" "Saintpaulia teitensis"

"Saintpaulia", commonly known as African violet, is a genus of 6 species of herbaceous perennial flowering plants in the family Gesneriaceae, native to Tanzania and adjacent southeastern Kenya in eastern tropical Africa, with a concentration of species in the Nguru mountains of Tanzania. The genus is most closely related to "Streptocarpus", with recent phylogenetic studies suggesting it has evolved directly from subgenus "Streptocarpella". The common name was given due to a superficial resemblance to true violets ("Viola", family Violaceae).

Taxonomy

The genus is named after Baron Walter von Saint Paul-Illaire (1860-1910), the district commissioner of Tanga province who "discovered" the plant in Tanganyika (now Tanzania) in Africa in 1892 and sent seeds back to his father, an amateur botanist in Germany. Two British plant enthusiasts, Sir John Kirk and Reverend W.E. Taylor, had earlier collected and submitted specimens to Royal Botanic Gardens, Kew in 1884 and 1887 respectively, but the quality of specimens was insufficient to permit scientific description at that time. The genus "Saintpaulia", and original species "S. ionantha", were scientifically described by J. C. Wendland in 1893.

Saintpaulias grow from 6-15 cm tall and can be anywhere from 6-30 cm wide. The leaves are rounded to oval, 2.5-8.5 cm long with a 2-10 cm petiole, finely hairy, and with a fleshy texture. The flowers are 2-3 cm diameter, with a five-lobed velvety corolla ("petals"), and grow in clusters of 3-10 or more on slender stalks (peduncles). Flower colour in the wild species can be violet, purple, pale blue, or white.

Several of the species and subspecies are endangered, and many more are threatened, due to clearance of their native cloud forest habitat for agriculture.

Revisions of the genus by B.L. Burtt had expanded the genus to approximately 20 species. On the basis of recent studies that showed most of the species to be very poorly differentiated, both genetically and morphologically, the number of species has been reduced to 6, with the majority of former species reduced to subspecies under "S. ionantha", in a recent floristic treatment (Darbyshire 2006).

Old name vs. current name

* "Saintpaulia amaniensis" = "S. ionantha" ssp. "grotei"
* "Saintpaulia brevipilosa" = "S. ionantha" ssp. "velutina"
* "Saintpaulia confusa" = "S. ionantha" ssp. "grotei"
* "Saintpaulia difficilis" = "S. ionantha" ssp. "grotei"
* "Saintpaulia diplotricha" = "S. ionantha" ssp. "ionantha" var. "diplotricha"
* "Saintpaulia grandifolia" = "S. ionantha" ssp. "grandifolia"
* "Saintpaulia grotei" = "S. ionantha" ssp. "grotei"
* "Saintpaulia intermedia" = "S. ionantha" ssp. "pendula"
* "Saintpaulia magungensis" = "S. ionantha" ssp. "grotei"
* "Saintpaulia magungensis" var. "minima" = "S. ionantha" ssp. "grotei"
* "Saintpaulia magungensis" var. "occidentalis" = "S. ionantha" ssp. "occidentalis"
* "Saintpaulia nitida" = "S. ionantha" ssp. "nitida"
* "Saintpaulia orbicularis" = "S. ionantha" ssp. "orbicularis"
* "Saintpaulia pendula" = "S. ionantha" ssp. "pendula"
* "Saintpaulia pendula" var. "kizarae" = "S. ionantha" ssp. "pendula"
* "Saintpaulia rupicola" = "S. ionantha" ssp. "rupicola"
* "Saintpaulia tongwensis" = "S. ionantha" ssp. "ionantha" var. "ionantha"
* "Saintpaulia velutina" = "S. ionantha" ssp. "velutina"

Cultivation

Saintpaulias are widely cultivated as house plants. Until recently, only a few of these species have been used in breeding programs for the hybrids available in the market; most available as house plants are cultivars derived from "Saintpaulia ionantha" (syn. "S. kewensis"). A wider range of species is now being looked at as sources of genes to introduce into modern cultivars.

Over 2,000 cultivars have been selected for horticultural use. There are many different leaf and flower types found; cultivars are classified as Large, Standard, Trailing, Semi-mini, Mini, and Micro with Micro being the smallest. They range in flower colour from white, pink, violet, dark red, yellow, and some even green, and the flowers may be either single (five petals) or double (more than five, with some or all of the stamens converted into extra petals). Flowers are not always a solid colour, but can also be found in the "fantasy" variety where the petals have strips of colours going down them. One interesting flower form found in the African Violet are known as a "wasp"; these flowers have the upper two flower petals independently fused forming a tube. There are also compound leaves on some, that are called "bustled".

Saintpaulias can be propagated by leaf cuttings (essential for propagating named cultivars) or seed (from which new cultivars are selected). African violets prefer a constant temperature between 20-25 °C (68-77 °F) with high humidity, and thrive best planted in well-drained humus or coir compost.

Some popular cultivars include 'Amazen Grace', 'Blue Border', 'Claret Queen', 'Dupont Blue', 'Ding Dong Trail', 'Glacier', 'Little Jewel', 'Mini Marina', 'Pink Miracle', and 'Porcelain'.

Diseases

References

* Darbyshire, I. 2006. Gesneriaceae. In H.J. Beentje & S.A. Ghazanfar (eds.), Flora of Tropical East Africa.

External links

* [http://www.avsa.org African Violet Society of America website]
* [http://www.violeteafricane.ro African Violet in Romania - Pasionata de violete africane]
* [http://avsc.ca African Violet Society of Canada website]
* [http://www.saintpauliasallskapet.se Swedish African Violet Society website]
* [http://www.saintpaulia.fi Finnish Saintpaulia Society website]
* [http://gesneriads.ca/saintart.htm Gesneriad Reference Web Saintpaulia article]
* [http://avflower.com/index_en.php Saintpaulia in Belarus]
* [http://www.africanvioletbooks.com African Violet Books]
* [http://www.violetvoice.com The Violet Voice, an online AV group]