Medicinal Plants

Medicinal (Steroidal) Yams (Dioscorea floribunda, Dioscorea deltoidea, Dioscorea composita)


  • Medicinal yams are robust, perennial, branched, climbers native to tropical Asia, Africa and South America. The underground rhizomes / tubers contain alkaloids like diosgenin, pannogenin and are used for the synthesis of antiarthritic, anti-inflammatory, antifertility, anabolic drugs.
  • The demand in India is estimated at 60 - 100 tonnes per annum. Tubers are collected from the wild growing plants in Jammu and Kashmir and Uttar Pradesh States and from cultivated plants in Karnataka and Tripura States.
  • The crop can be grown as an irrigated crop in Andhra Pradesh in light and medium textured, deep soil rich in organic matter.


  • FB(C)t, Arka, Upkar are the improved varieties of steroidal yams.


  • Steroidal yams can be propagated through tubers / rhizomes, stem cuttings or seeds. Commercial plantations are raised through tuber pieces.
  • Tubers give three kinds of pieces namely crown (low alkaloid content), medium and tips (high in alkaloids). Crown (Stem ends) are used for planting as they sprout early.
  • 50 - 60 g pieces of crowns are planted in raised nursery beds in shade covered with stand and regularly watered. After 30 days the crowns sprout and are ready for planting.
  • About 2.5 tonnes of crown are required for planting one hectare.


  • The land is brought to fine tilth by ploughing twice, harrowing and planking. 15 - 20 tonnes of farm yard manure, 950 kg of single superphosphate, 250 kg of muriate of potash and 25 - 50 kg of zinc sulphate per hectare are applied basally.
  • Planting is done in February - March with a spacing of 60 - 90 cm between rows and 30 - 45 cm between plants and the field is immediately irrigated. The field is irrigated frequently till the crop establishes, thereafter at 10 - 15 days intervals during non-rainy periods.
  • The crop needs support for optimum growth. 1.95 meters high stone pillars spaced at 9 meters apart and connected with G.I wires of 12 gauge are used for erecting trellis. The vines are trained on to this support.

Interculture - Fertilizers

  • The field is periodically weeded. Intercropping with legumes like Cowpea, Horsegram, French bean etc., gives bonus yields and extra income without affecting the yield of medicinal yams.
  • The crop is fertilized with 450 - 650 kg urea per hectare in 3 equal splits. Spraying of micronutrients and growth regulators is advocated for good results.

Pests and Diseases

  • Aphids and Red spider mites cause damage to the crop occasionally. Spraying of Rogor (2 ml/litre of water) or Kelthane (3 g/litre of water) controls these insects.

Harvesting - Profits

  • Two to three years old crop is harvested in February - March. The tuber / rhizomes are dug out, cleaned of adhering soil and dried. The crop on an average gives 5 - 7 tonnes (2 year) or 6 - 8 tonnes (3 year) of dried tubers and more than Rs. 25,000 net profit per hectare.

There is no organised market in Andhra Pradesh. Therefore, farmers are advised to make market arrangements before starting cultivation.