Quantification of adaptability and stability among genotypes/cultivars for root yield in Ashwagandha (Withania somnifera L.)

•Ashwagandha is an ancient plant used in the Indian, Ayurveda and Unani systems of medicine.•The AMMI method used Withania somnifera crop for the first time.•This is a very efficient model for the interpretation regarding the causes of stability.•Six genotypes W 20, W 1 (cv. Pratap), w2, w3 (cv. Chetak), W4 and W6 exhibited widest adaptability.

Ashwagandha (Withania somnifera L.), is one of the very important medicinal plant in Ayurveda since ancient times. It is a native of Mediterranean region grows wildly in arid and semi arid parts of India. Under the germplasm enhancement programme, thirty genetic stocks/cultivars of ashwagandha originated from selective divergence belongs to eight states of India (U.P., M.P., Rajasthan, Maharashtra, Kerala, J and K., A.P. and W.B.) were evaluated in the four consecutive years for the estimation of stability/adaptability. Using the AMMI model, ashwagandha genetic stocks namely, W 20, W 1 (cv. Pratap), W 2, W 3 (cv. Chetak), W 4 and W 6 (cv.Poshita) were expressed the high adaptability and stability for root yield over years. Therefore, above six selected genetic stocks/varieties recommended for commercial cultivation in India on large scale.