San: Aswagandha, Varahakarni
Hin: Asgandh, Punir Mal: Amukkuram
Importance: Indian ginseng or Winter cherry is an erect branching perennial undershrub which is considered to be one of the best rejuvenating agents in Ayurveda. Its roots, leaves and seeds are used in Ayurvedic and Unani medicines, to combat diseases ranging from tuberculosis to arthritis. The pharmacological activity of the plant is attributed to the presence of several alkaloids and withaniols. Roots are prescribed in medicines for hiccup, several female disorders, bronchitis, rheumatism, dropsy, stomach and lung inflammations and skin diseases. Its roots and paste of green leaves are used to relieve joint pains and inflammation. It is also an ingredient of medicaments prescribed for curing disability and sexual weakness in male. Leaves are used in eye diseases. Seeds are diuretic. It is a constituent of the herbal drug ‘Lactare’ which is a galactagogue.
Aswagandha was observed to increase cell-mediated immunity, prevent stress induced changes in adrenal function and enhance protein synthesis. Milk fortified with it increases total proteins and body weight. It is a well known rejuvenating agent capable of imparting long life, youthful vigour and intellectual power. It improves physical strength and is prescribed in all cases of general debility. Aswagandha powder (6-12g) twice a day along with honey and ghee is advised for tuberculosis in Sushruta Samhita. It also provides sound sleep (Prakash, 1997).
Distribution: Aswagandha is believed to have oriental origin. It is found wild in the forests of Mandsaur and Bastar in Mandhya Pradesh, the foot hills of Punjab, Himachal Pradesh, Uttar Pradesh and western Himalayas in India. It is also found wild in the Mediterranean region in North America. In India it is cultivated in Madhya Pradesh, Rajastan and other drier parts of the country.
Botany: Aswagandha belongs to the genus Withania and family Solanaceae. Two species, viz, W. coagulans Dunal and W. somnifera Dunal are found in India. W. coagulans is a rigid grey under shrub of 60-120cm high. W. somnifera is erect, evergreen, tomentose shrub, 30-75cm in height. Roots are stout, fleshy, cylindrical, 1-2cm in diameter and whitish brown in colour. Leaves are simple, ovate, glabrous and opposite. Flowers are bisexual, inconspicuous, greenish or dull yellow in colour born on axillary umbellate cymes, comprising 5 sepals, petals and stamens each; the two celled ovary has a single style and a bilobed stigma. The petals are united and tubular. The stamens are attached to the corolla tube and bear erect anthers which form a close column or cone around the style. Pollen production is poor. The fruit is a small berry, globose, orange red when mature and is enclosed in persistent calyx. The seeds are small, flat, yellow and reniform in shape and very light in weight. The chromosome number 2n = 48.
The cultivated plants have sizable differences from the wild forms not only in their morphological characters but also in the therapeutical action, though the alkaloids present are the same in both (Kaul, 1957). Some botanists, therefore, described the cultivated plant distinct from wild taxa and have coined a new name W. aswagandha (Kaul, 1957) which is contested by Atal and Schwarting (1961).
Agrotechnology: Asgandh is a tropical crop growing well under dry climate. The areas receiving 600 to 750mm rainfall is best suited to this crop. Rainy season crop requires relatively dry season and the roots are fully developed when 1-2 late winter rains are received. Sandy loam or light red soils having a pH of 7.5- 8.0 with good drainage are suitable for its cultivation. It is usually cultivated on poor and marginal soils. Withania is propagated through seeds. It is a late kharif crop and planting is done in August. Seeds are either broadcast-sown or seedlings are raised in nursery and then transplanted. Seed rate is 10-12 kg/ha for broadcasting and 5kg/ha for transplanting. In direct sown crop plants are thinned and gap filling is done 25-30 days after sowing. Seeds should be treated with Dithane M-45 at 3g/kg of seeds before sowing. Seeds are sown in the nursery just before the onset of rainy season and covered with light soil. Seeds germinate in 6-7 days. When seedlings are six weeks old they are transplanted at 60cm in furrows taken 60cm apart. The crop is mainly grown as a rainfed crop on residual fertility and no manure or fertilizers are applied to this crop generally. However, application of organic manure is beneficial for realizing better yields. It is not a fertilizer responsive crop. One hand weeding 25-30 days after sowing helps to control weeds effectively. No serious pest is reported in this crop. Diseases like seedling rot and blight are observed. Seedling mortality becomes serious under high temperature and humid conditions. The disease can be minimized by use of disease free seeds and treatment with thiram or deltan at 3-4g/kg seed before sowing. Further, use of crop rotation, timely sowing and keeping field well drained also protect the crop. Spraying with 0.3% fytolan, dithane Z-78 or dithane M-45 will help controlling the disease incidence. Spraying is repeated at 15 days interval if the disease persists. Aswagandha is a crop of 150-170 days duration. The maturity of the crop is judged by the drying of the leaves and reddening of berries. Harvesting usually starts from January and continues till March. Roots, leaves and seeds are the economical parts. The entire plant is uprooted for roots, which are separated from the aerial parts. The berries are plucked from dried plants and are threshed to obtain the seeds. The yield is 400-500kg of dry roots and 50-75kg seeds per hectare.
Post harvest technology: The roots are separated from the plant by cutting the stem 1-2cm above the crown.
Roots are then cut into small pieces of 7-10cm to facilitate drying. Occasionally, the roots are dried as a whole. The dried roots are cleaned, trimmed, graded, packed and marketed. Roots are carefully hand sorted into the following four grades.
Grade A: Root pieces 7cm long, 1-1.5cm diameter, brittle, solid, and pure white from outside.
Grade B: Root pieces 5cm long, 1cm diameter, brittle, solid and white from outside.
Grade C: Root pieces 3-4cm long, less than 1cm diameter and solid. Lower grade: Root pieces smaller, hollow and yellowish from outside.
Properties and activity: Aswagandha roots contain alkaloids, starch, reducing sugar, hentriacontane, glycosides, dulcital, withaniol acid and a neutral compound. Wide variation (0.13-0.31%) is observed in alkaloid content. Majumdar (1955) isolated 8 amorphous bases such as withanine, somniferine, somniferinine, somnine, withananine, withananinine, pseudowithanine and withasomnine. Other alkaloids reported are nicotine, tropine, pseudotropine, 3, -tigloyloxytropane, choline, cuscudohygrine, anaferine, anahygrine and others. Free aminoacids in the roots include aspartic acid, glycine, tyrosine, alanine, proline, tryptophan, glutamic acid and cystine. Leaves contain 12 withanolides, alkaloids, glycosides, glucose and free amino acids. Berries contain a milk coagulating enzyme, two esterases, free amino acids, fatty oil, essential oil and alkaloids. Methods for alkaloid’s analysis in Asgandh roots have also been reported (Majumdar, 1955; Mishra, 1989; Maheshwari, 1989). Withania roots are astringent, bitter, acrid, somniferous, thermogenic, stimulant, aphrodisiac, diuretic and tonic. Leaf is antibiotic, antitumourous, antihepatotoxic and antiinflammatory. Seed is milk coagulating, hypnotic and diuretic.