and subcultured every four weeks on propagation medium (Tan et al, 2005). The callus growth rate was calculated using the equation described by Yokata (1999). Two g of calli (fresh weight, FW) were inoculated into 50 cm3 Murashige and Skoog (1962), (MS) liquid media supplemented with 1 mg L-1 NAA and biotin, 2 mg L-1 2,4-D, 0.1 mg L-1 L-glutamine and myo-inositol and 30 g dm-3 sucrose. The cultures were incubated in 16/8 h light and dark conditions with continuous shaking (80 rpm) and were maintained through routine transfer of small aliquots of the suspension into a fresh medium at every two weeks. Independent experiments were carried out in a minimum of three replicates.