Material and methods
Plant materials
Three different sources of plant materials were used in this study i.e. rhizomes, callus and cell suspension cultures. Field grown rhizomes were washed thoroughly under running tap water for 30 min before being sliced and oven dried. The establishment of callus culture was carried out according to the procedures outlined in Yusuf et al. (2011). All experiments were performed with 30 replicates. One to 1.5 cm in diameter sized calli were cultured in initiation media