Effects of Complex Organic Extracts on Plantlet Regeneration from PLBs and Plantlet Growth in the Doritaenopsis Orchid

Potato extract (PE), corn extract (CE) and papaya extract (PAE) significantly enhanced plantlet regeneration from PLBs (protocorm-like bodies) when 50 mL L - 1 of an extract was supplemented to the New Phalaenopsis (NP) medium containing sucrose. Among the treatments, CE 50 mL L - 1 induced the highest rate (66.63%) of plantlet regeneration from PLBs. Organic extracts of potato, corn and papaya at 50-100 mL L - 1 in NP medium also enhanced the subsequent growth of mini-plantlets. However, a higher level (200 mL L - 1 ) of extract in the medium inhibited the growth of the plantlets. Among these extracts, PE at 100 mL L - 1 showed the optimum effect on the acceleration of shoot growth while CE at the same concentration was optimum for root growth.