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Withania somnifera
 Withania somnifera, known commonly as ashwagandha,[2][3][4] is an evergreen shrub in the Solanaceae or nightshade family that grows in Nepal, India, the Middle East, and parts of Africa. Several other species in the genus Withania are morphologically similar.[3] The plant, particularly its root powder, has been used for centuries in traditional Indian medicine.[5] Ashwagandha supplements, typically containing root or leaf powder or extracts, are commonly sold.[4] Its use in herbal medicine and dietary supplements notwithstanding, there is insufficient scientific evidence that W. somnifera is safe or effective for treating any health condition or disease.[3][4] DescriptionThis species is a short shrub growing 35–75 cm (14–30 in) tall. Tomentose branches extend radially from a central stem. Leaves are dull green, elliptic, usually up to 10–12 cm (3.9–4.7 in) long. The flowers are small, green and bell-shaped. The ripe fruit is orange-red.[3] EtymologyThe Latin species name somnifera means 'sleep-inducing'.[6] The name ashwagandha is a combination of the Sanskrit words ashva, meaning 'horse', and gandha, meaning 'smell', reflecting that the root has a strong horse-like odor.[3] CultivationW. somnifera is cultivated in many of the drier regions of India. It is also found in Nepal, Sri Lanka, China, and Yemen.[7][8] It prefers dry stony soil with sun to partial shade. It can be propagated from seeds in the early spring or from greenwood cuttings in the later spring.[9] Diseases and pestsWithania somnifera is prone to several pests and diseases. Leaf spot disease caused by Alternaria alternata is the most prevalent disease, which occurs in a severe form in Punjab, Haryana, and Himachal Pradesh. Leaf spot disease reduces the concentration of its secondary metabolites.[10] The leaves are also prone to Alternaria dianthicola in India.[11] A treehopper (Oxyrachis tarandus) feeds on the apical portions of the stem, making them rough and woody in appearance and brown in colour.[12] The carmine red spider mite (Tetranychus urticae) is the most prevalent pest of the plant in India.[13] In recent years, this plant has been serving as a new reservoir host for an invasive mealybug species Phenacoccus solenopsis.[14] PhytochemistryThe main phytochemical constituents of W. somnifera are withanolides, a group of triterpene lactones that include withaferin A, alkaloids, steroidal lactones, tropine, and cuscohygrine.[3] Forty withanolides, twelve alkaloids, and various sitoindosides have been isolated from this plant species.[3][15] As these withanolides are structurally similar to the ginsenosides of Panax ginseng, W. somnifera is commonly referred to as "Indian ginseng".[3] ResearchLimited clinical studies have found that supplementation with various ashwagandha extracts may decrease anxiety and perceived stress, and improve sleep.[3][4][16] As the studies used different extract preparations, durations of use, doses, and types of subjects, it remains undetermined how ashwagandha may have effects in people, as of 2023.[3][4][16] Adverse effectsW. somnifera may cause adverse effects if taken alone or together with prescription drugs.[3][4][17] The most common side effects include diarrhea, headache, sedation, or nausea, and the product should not be used during pregnancy or breastfeeding.[4][17] Ashwagandha may increase testosterone levels which could adversely interact with cancer medications.[3][16][17] Gallery
References Look up ashwagandha in Wiktionary, the free dictionary.
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