Agrochimica, Vol. 61 No. 3 July-September 2017 Organic nutrient sources influence yield and quality of ashwagandha (Withania somnifera), and soil biochemical properties S.R. Chaudhary 1 , Jitendra Kumar 2 , A.P. Chaudhary 3 , B.B. Basak 2,* 1 Department of Soil Science and Agricultural Chemistry, Anand Agricultural University, Anand 388110, India 2 ICAR, Directorate of Medicinal and Aromatic Plants Research, Boriavi 387310, Anand, India 3 Department of Agricultural Statistics, Anand Agricultural University, Anand 388110, India Received 24 June 2017 - Received in revised form 8 September 2017 - Accepted 13 September 2017 Keywords: ashwagandha, bioactive compounds, organic fertilizers, microbial biomass carbon, soil enzymes Summary. – A field experiment was conducted to study the effect of organic nutrient management on yield and quality parameters in ashwagandha (Withania somnifera) as well as soil biochemical properties. The experiment was laid out in a split plot design with three replications. The organic manures (farmyard manure, vermicompost and castor cake) were applied as main plot treatments, and biofertilizers and jivamrut were applied in different combination as subplot treatments. The results indicate that the application of organic fertilizers invariably improved root growth, yield and total withanolide content in ashwagandha. The highest dry root yield (714.6 kg ha -1 ) and total withanolide content (0.91 mg g -1 ) were recorded with application of castor cake, which was at par with vermicompost. Soil available nutrients and biochemical properties were significantly improved under vermicompost and castor cake applications as compared to other treatments. Thus, organic manures, particularly castor cake and vermicompost, could be a promising source of nutrients in organic cultivation of ashwagandha. Introduction. – Ashwagandha (Withania somnifera L. Dunal) is one of the important medicinal plants used in the traditional Indian medicine since ancient times. It belongs to the Solanaceae family and is native to the Indian subcontinent. The plant grows erect to a height of 35-75 cm having small green-coloured flowers and orange-red ripe fruits. Ashwagandha, commonly called ‘winter cherry’, is a dryland medicinal plant. The root is the economic part of the plant and is used in the preparation of Ayurveda and Unani medicines. It is also used for cur- ing carbuncles in the indigenous system of medicine. Apart from its use in promoting physical and mental health, the root also provide defence against diseases and arrest the ageing process (Bhattacharya et al., *  Corresponding author: biraj.ssac@gmail.com DOI 10.12871/00021857201724 MANCANO RIFERIMENTI ALLE TABELLE 2 E 5. La tabella 2 l’ho messa prima della tabella 3 e la tabella 5 prima della tabella 6