Effects of Carbohydrates on Callus Growth and Callus Derived Plantlet Regeneration in Doritaenopsis Orchid

Doritaenopsis callus utilized sucrose, maltose and sorbitol as energy sources for the growth and development, where each carbohydrate elicited a different response. Calli on sucrose supplemented New Phalaenopsis (NP) medium grew well and remained friable, bright yellow and translucent, similar to source calli, but turned green and produced Protocorm Like Bodies (PLBs) on maltose and sorbitol supplemented media. Sucrose supplemented medium was the best for callus growth over maltose and sorbitol. The initiation of PLBs from calli on maltose medium was the highest followed by sorbitol medium while the sucrose medium did not produce PLB. Sorbitol affected most intensively plantlet regeneration from PLBs over maltose and sucrose. However, maltose supplemented medium markedly enhanced the subsequent growth and development of regenerated mini plantlets over sorbitol and sucrose media.