SOIL TEST BASED INTEGRATED PLANT NUTRITION SYSTEM FOR ASHWAGANDHA ON INCEPTISOLS.

An experiment was conducted on Vertic Ustropept following Ramamoorthy's Inductive cum targeted yield model to elucidate the relationship between soil test values and response of ashwagandha (Withania somnifera (L.) Dunal) to added fertilizers under Integrated Plant Nutrition System (IPNS). Nutrient requirement and contribution from soil, fertilizers and FYM were calculated. The percent contribution from soil, fertilizer and FYM were 19.03, 31.30 and 23.14 for N; 20.26, 17.30 and 6.38 for P2O5; 11.08, 62.53 and 30.39 for K2O. Fertilizer prescription equations were developed for ashwagandha and nomograms were formulated based on the equations for a range of soil test values and desired target yield under IPNS. Following IPNS practice (NPK+ FYM @12.5 t ha-1), 40, 24 and 30 kg ha-1 of fertilizer N, P2O5 and K2O respectively, could be saved. [ABSTRACT FROM AUTHOR]