Withania somnifera, known commonly as ashwagandha,Indian ginseng,poison gooseberry, or winter cherry, is a plant in the Solanaceae or nightshade family. Several other species in the genus Withania are morphologically similar. It is used as an herb in Ayurvedic medicine.
Withania somnifera is prone to several pests and diseases. Leaf spot disease caused by Alternaria alternata is the most prevalent disease, which is most severe in the plains of Punjab, Haryana, and Himachal Pradesh. Biodeterioration of its pharmaceutically active components during leaf spot disease has been reported. The Choanephora cucurbitarum causes a stem and leaf rot of Withania somniferaOxyrachis tarandus, a treehopper, feeds on the apical portions of the stem, making them rough and woody in appearance and brown in colour. The apical leaves are shed and the plant gradually dies. The carmine red spider mite (Tetranychus urticae) is the most prevalent pest of the plant in India.
The plant's long, brown, tuberous roots are used for medicinal purposes.
In Ayurveda, the berries and leaves are applied externally to tumors, tubercular glands, carbuncles, and ulcers. The roots are used to prepare the herbal remedy ashwagandha, which has been traditionally used to treat various symptoms and conditions.
In two published clinical trials of W. somnifera, the side effects were not significantly different from those experienced by placebo-treated individuals. In the clinical trial of Cooley et al. (2009), Ashwagandha exhibit greater clinical benefit than psychotherapy in mental health (anxiety level), concentration, fatigue, social functioning, vitality, and overall quality of life.
Also, ashwagandha may act as an abortifacient and has traditionally been used in this role. 
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^ abPandit, S.; Chang, K.-W.; Jeon, J.-G. (February 2013). "Effects of Withania somnifera on the growth and virulence properties of Streptococcus mutans and Streptococcus sobrinus at sub-MIC levels". Anaerobe19: 1–8. doi:10.1016/j.anaerobe.2012.10.007.
^Pati, P. K.; Sharma, M.; Salar, R. K.; Sharma, A.; Gupta, A. P.; Singh, B. (2009). "Studies on leaf spot disease of Withania somnifera and its impact on secondary metabolites". Indian Journal of Microbiology48 (4): 432–437. doi:10.1007/s12088-008-0053-y. PMC3476785. PMID23100743.edit
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^Ahmad, M. K.; Mahdi, A. A.; Shukla, K. K.; Islam, N.; Rajender, S.; Madhukar, D.; Shankhwar, S. N.; Ahmad, S. (2010). "Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile males". Fertility and Sterility94 (3): 989–996. doi:10.1016/j.fertnstert.2009.04.046. PMID19501822. edit
^ abCooley, K.; Szczurko, O.; Perri, D.; Mills, E. J.; Bernhardt, B.; Zhou, Q.; Seely, D. (2009). "Naturopathic Care for Anxiety: A Randomized Controlled Trial ISRCTN78958974". In Gagnier, Joel. PLoS ONE4 (8): e6628. doi:10.1371/journal.pone.0006628. PMC2729375. PMID19718255. edit
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