Effect of N, P and K on the growth of Costus speciosus (Koening) Smith

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.