Abstract:
A field trial was conducted to find out the role of major nutrients on different
growth characters of Costus speciosus and the important characters which had a
bearing on diosgenin yield were identified. The results showed that N application
increased the growth of plants in terms of height, length and breadth of leaves, area
per leaf and total leaf area per plant. P had a depressing effect, especially on the
number of leaves and area per leaf. The beneficial effect of K was only marginal,
as compared to that of N. Application of N increased the yield of rhizomes. The
diosgenin content of the rhizomes was found to be significantly influenced by N, P
and K application while the yield of diosgenin was significantly influenced by different
levels of N and K. Of the growth characters studied, the total leaf area and
plant height were found to be significantly correlated with diosgenin yield.