MEDICINAL AND AROMATIC CROPS (2+1)

Harvesting, yield and processing

Studies have shown that the growing of D. floribunda as a two-year crop is economical. An average yield of 15 to 20 t/ha of fresh tubers can be obtained during the first year, and up to 40 to 50 t/ha during the second year. The diosegnin content of the tubers tends to increase, on an average, from 2.5-3.0% in the first year to 3.0-3.5% in the second year. The cost of cultivation is, however, much less during the second year.
The D. deltoidea should be harvested only after three years to get the optimum yield from the crop with the maximum diosgenin content. Generally, the tubers are harvested during February-March. Harvesting can be done by manual labour with pickaxes. The tubers are harvested when the plants are in a dormant condition to obtain the maximum yield of diosgenin.

Processing
The tubers are dried under sun to 6-7 per cent moisture which takes about a week to fully dry the material. The dried tubers are solvent extracted to isolate diosgenin.