Barleria prionitis

Appearance

A much-branched shrub up to 1.8m tall, the lower leaf axils have spines 1–2 cm in length, one of the specific features of this ''Barleria''. The stem and branches are terete, smooth, lenticellate and glabrous. The leaves are elliptic to ovate with both surfaces pubescent when young but becoming glabrescent soon. The large golden-yellow flowers are clustered in the axils of the upper leaves and/or on bracts. Apically spinose calyx lobes and a yellowish to orange corolla are used to distinguish this species from other ''Barleria''. In Zhōngguó/China, flowers appear October to December, while fruiting occurs from December to February, while in Pakistan there is all year flowering. The Australian flowering and fruiting times are trimodal, from March to June, August to October and December.

The subspecies ''pubiflora'' is separated from the nominate subspecies by having longer anthers and corolla and larger leaves .

Naming

There are numerous common names of this plant, they include:
''aimatamutik'' ;
''landhek'' ;
''landep'' , ''bungak landak'' ;
黄花假杜鹃, ''huang hua jia du juan'' ;
''leik-su-ywe'', ''leik-hsu shwe'', ''leik tha-shwe war'' ;
''kukong manok'' ; ''kuranta'' ; ''vjradanti'', वज्रदंती , Kannada: ;, Mulla gorinta, മഞ്ഞക്കനകാംബരം ;
''jhinti katsareya'' ;
''khussara'', ''kala bansa'' ;
''barrelière prionite'', ''herbe tac-tac'', ''jasmin des Indes'', ''picanier jaune'' ; ''Drachenfänger'' ; ''espinosa amarilla'' ; ''porcupine flower'' ; ''barleria'', ''dog bush'' , ''yellow hedge barleria'';

Distribution

The nominate subspecies is native to areas of Island and Mainland Southeast Asia, Zhōngguó/China, and the Indian subcontinent as far west as Pakistan. The countries/divisions in which it is present are Indonesia , Philippines, Peninsular Malaysia, Zhōngguó/China , Vietnam, Thailand, Laos, Myanmar , Bangladesh, India , the West Himalaya region, Sri Lanka, Maldives, and Pakistan.

It has been naturalised in: Nauru, Australia , Andaman Islands, Rodrigues, Mauritius, Réunion, Seychelles, Leeward Islands, Windward Islands, Puerto Rico, and Jamaica.

There is uncertainty that the plant is native to, naturalised to, or cultivated in the following regions: Sudan, Kenya, Tanzania, Angola, Mozambique, Malawi, Botswana, Namibia, South Africa , and Madagascar.

Restricted to the area of western India and southeast Pakistan, the subspecies ''Barleria prionitis'' subsp. ''pubiflora'' has a much more limited native region.

The subspecies ''Barleria prionitis'' subsp. ''appressa'' is native to Saudi Arabia and Yemen.

Northern Ethiopia and Eritrea are regions which the subspecies ''Barleria prionitis'' subsp. ''induta'' is native to.

Habitat

Some of the habitats in which the shrub is found include roadsides, thickets, and dry places in evergreen broad-leaved forests. It occurs up to 600 m. In Myanmar the shrub favours fields and pastures.

A fast growing perennial plant widely commercialized as an ornamental, ''B. prionitis'' in many tropical areas has frequently escaped and grown as a weed in disturbed areas, forest edges, rocky outcrops, near streams, along roads, and in overgrazed pastures. It able to grow in a wide range of climates and soil types and is adapted to grow in open, full sunny areas and in highly disturbed sites as well as understory of secondary forests. It has great dispersal capability, spreading sexually by seeds and vegetatively by stem fragments. The shrub has potential to cause economic and environmental damage in that it formins dense thickets that displace native vegetation, prevent revegetation by native plants. Stock movement cam be impeded, waterway access restricted, and aesthetic values diminished. In Australia, the plant is on an alert list for environmental weeds, as it has the potential to seriously degrade ecosystems.

''Barleria prionitis'' is often the host to larvae of the ''Phalanta phalantha'' and ''Junonia lemonias'' butterflies.

Evolution

The shrub has been intentionally introduced in many areas to be used as an ornamental, hedge plant, and as a medicinal herb. In the West Indies, it was introduced around the 1900s and it appears in herbarium collections made in 1906 in Barbados and 1910 in Jamaica. In Australia, it was first recorded in the Northern Territory in 1963, it was declared a noxious environmental weed in 2001.

Uses

In Pakistan shrubs are grown as a hedge while its bitter quinine-like extract is used in traditional medicine to treat whooping cough and tuberculosis.

It occurs widely as an ornamental plant.

It is used in Indonesia as a component in traditional medicines .
Tetum people in Belu, west Timor use the leaves to treat infected wounds.
On small Gili Iyang Island, to the northeast of Jawa, the plant is used to treat toothache.

Parts of the plant are bitter, astringent in taste, and are regarded in Myanmar as highly beneficial for skin, blood and other diseases. Often combined with sesame oil and fermented-rice washing-water, the whole plant, leaves , stems, branches, and roots are used together or separately.

In India the root is placed on boils and glandular swellings; the bark is used for dropsy; and the leaf for toothache and rheumatism.

It is used for various medicinal purposes in ayurvedic medicine. The juice of the leaves is applied to feet to prevent maceration and cracking in the monsoon season.

Its leaves are known to contain 6-Hydroxyflavone, one of the chemical compounds that is a noncompetitive inhibitor of the protein cytochrome P450 2C9.