| Wrightia tinctoria | |
|---|---|
 | |
| Flowers | |
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Gentianales |
| Family: | Apocynaceae |
| Genus: | Wrightia |
| Species: | W. tinctoria |
| Binomial name | |
| Wrightia tinctoria | |
Wrightia tinctoria,Pala indigo plant ordyer's oleander,[1] is a flowering plant species in the genusWrightia found in India,southeast Asia andAustralia. It is found in dry and moist regions in its distribution. Various parts of the plant have been used intraditional medicine, but there is noscientific evidence it is effective or safe for treating any disease.
It is a small to medium-sized deciduous shrub or tree, ranging from 3–15 m (10–49 ft) in height[2] but also reaching up to 18 m.[3] The bark is smooth, yellowish-brown and about 10 mm thick, producing a milky-whitelatex. Leaves aresimple,oppositely arranged, ovate, obtusely acuminate and are 10–20 cm long and 5 cm wide. Leaves areglabrous and sometimespubescent beneath.[2] Leaf stalks are very short. The flowers appear (in India) from March to May, peaking from April to June.[2][3] White flowers appear incorymb-likecymes, 5–15 cm across, at the end of branches. Flowers have five white petals 2–3 cm long which turn creamish yellow as they age. The flowers have oblong petals which are rounded at the tip, and are similar to flowers offrangipani. Fruiting is in August[2] and the fruit is cylindrical, blackish-green speckled with white, long horn-like and united at tip. The seeds are brown and flat with bunch of white hairs.[3]Seed dispersal is by wind andpollination is by insects.[3] In his 1862 book on timber trees ofSouth Asia,Edward Balfour mentions its distribution across the thenMadras Presidency ofBritish India especially in theCoimbatore jungles, and reports that it was "very common in all forests of Bombay".[4] In the same book, Balfour quotesWilliam Roxburgh's comparison of the whiteness of the wood as "coming nearer toivory than any I know". Earlier in 1824, the plant specimens were presented by theBritish East India Company to theRoyal Horticultural Society as illustrated and recorded inbotanical register founded bySydenham Edwards and at the time published byJames Ridgway.[5]
The plant containswrightial, atriterpenoidphytochemical,[6] along withcycloartenone,cycloeucalenol,β-amyrin, andβ-sitosterol isolated from the methanol extract of the immature seed pods.
The following are considered to besynonyms ofWrightia tinctoria:[7]
It is mainly found inAustralia,India,Myanmar,Nepal,Timor andVietnam.[2] Within India, it is found in most of the peninsular and central India except the northern and north-eastern states.[3]
It is a slow to moderate-growing plant. Plants commence flowering when about 5–8 years old. It grows in a wide range of soil types ranging from arid, semi-arid, gravely or rocky soils and moist regions, especially on dry sandy sites or hillsides and valleys. The tree responds well to coppicing, and also produces root suckers.[2] It tolerates moderate shading and is often found as undergrowth in deciduous forests.[2] It also tolerates high uranium levels in soils.[2] In India, the fungusCercospora wrightia is known to causeleaf spot disease of Wrightia tinctoria.[8]
The flowers, leaves, fruits and seeds are edible.[8] The tree is harvested from the wild as a medicine and source of a dye and wood. Leaves are extracted as fodder for livestock. The leaves, flowers, fruits and roots are sources of indigo-yieldingglucoside, which produces a blue dye or indigo- like dye. About 100–200 kilos of leaves are needed to prepare 1 kilo of dye.[2] It is occasionally planted as an ornamental in the tropics. The branches are trampled into the puddle soil in rice field for green manuring. It is recommended as a good agroforestry species as itintercrops well.[2] High levels of extraction is resulting in it becoming scarce in some regions.[8] The sap added to milk has been reported to have preservative properties; the milk will remain fresh for some time, the taste remaining unaltered.[8]
InAyurveda and othertraditional medicine practices, the plant is calledshwetha kutaja and its seeds are calledindrayava orindrajava.[9] There is nohigh-quality clinical evidence that it is safe or has any beneficial effect.
The white wood is used forturnery, carving, toy making,matchboxes, small boxes and furniture. The wood ofWrightia tinctoria, colloquially calledAale mara (ivory-wood),[10] is used extensively inChannapatna (a toy town of India) for carving and lacquer work of world famousChannapatna toys.[11] The timber is high in quality and valuable.
wrightia tinctoria.
