Productivity, quality and economics of ashwagandha (Withania somnifera) as influenced by irrigation and fertility levels under drip irrigation system

An experiment was conducted at Bhubaneswar (Orissa) during rabi seasons of 2005–06 and 2006–07 to study the effect of drip irrigation regimes and fertigation levels on performance of ashwagandha (Withania somnifara (L.) Dunal), cultivated in the rice (Oryza sativa L.) fallow. The treatments included three irrigation regimes (1,-drip irrigation at 100% PE, I, at 80% PE and I, at 60% PEl and three fertility levels (100%, 75% and 50% recommended dose of 30-30-20 kg N-P-K/ha) with an extra (control) treatment having surface irrigation and soil application of fertilizer. Maximum root yield (795 kg/ha) and seed yield (78 kg/ha) were obtained through irrigation at 80% PE followed by 100% PE and 60% PE. Application of full dose of fertilizer (100% RD) produced maximum quantity of roots (745 kg/ha), which was 4.9% and 12.9% more than that of 75% (710 kg/ha) and 50% RD (660 kg/ha). The maximum alkaloid and withanolides content in the roots was obtained under drip fertigation. Irrigating the crop at 80% PE with recommended dose of fertilizer (100% RD) produced highest root yield (862 kg/ha), seed yield (82 kg/ha), net return (47,029/ha) with benefit-eost ratio of 1.73.