Distribution and Habitat:  It is seen in Tropical Himalaya, Sikkim, West Peninsula of India, Sri Lanka;Myanmar.

Botany:  Handsome glabrous twining shrub, roots thick, irregularly twisted;  Stem glabrous, laticiferous. 

• Leaves: Simple, opposite, cordate, petioles long, lamina cordiform to oblong, chartaceous, puberlous, penni-nerved’
• Inflorescence: Cymes axillary, umbellate, few flowered; Flowers purple in axillary umbellate cymes.
• Fruit: Follicle short, thick, smooth, acute.

Properties: Cooling, digestive, alternate, aphrodisiac, emollient, expectorant, galactagogue, ophthalmic, refrigerant, sweet and tonic.

Chemical constituents:  Bark: α-amyrin, β-sitosterol, lupeol, alanine, aspartic acid, glycine, serine, threonine, and valine.

Uses: Eye troubles, blood vomiting, decaying, burning sensation, removes deranged bile, fever, constipation and cough.

Formulations: Vidaryadiganam, Dhanwandharam taila,  Balarishta.

Agro technology: 

Soil and Climate: Prefers a tropical climate with high rainfall and relative humidity. Soil should be light and porous permitting root development. 

Propagations:   Vegetatively by stem cuttings,  mainly by seeds.

Irrigation: Regular irrigation is to be given till flowering. 

Manures and Fertilizers: Application of 20 t /ha of farm yard manure , 100 kg/ ha bone meal, 500 kg /ha of neem cake, 2 kg/ha each of Trichoderma and AM fungi sustain good growth of plants. Wherever growth of plant is slow this can be supplemented with NPK, each @ 50 kg /ha split application spreading to second year is necessary. 

Plant protection: Fungal diseases like leaf spot and leaf blight are commonly seen. It can be controlled by spraying 1% Bordeaux mixture. Leaf eating caterpillars are common which can be controlled by manual picking. 

Harvesting: Harvesting can be done at the end of the second year when the vines start drying up. Roots are collected by deep digging and cleaned thoroughly in water. .

Processing: The tubers are cut in to pieces of 10 cm length and dried in sun before sale.