Rapid in vitro propagation of orchid Zygopetalum intermedium

The influence of plant growth substances; medium and potting mixture on protocorm development, differentiation, growth and establishment of Zygopetalum intermedium was assessed. Embryo from mature green but unripe capsule cultured on half strength Murashige and Skoog medium containing 1.5 g l(-1) AC with 0.25 mg l(-1) PBZ and 0.1 mg l(-1) of NAA swollen in 59.7 days, followed by formation of globular bodies in 64 days and protocorm development in 70.7 days. Nitsch medium in combination with 0.5 mg l(-1) of BAP and 0.25 mg l(-1) of Triacontanol resulted in shoot and root differentiation and maximum plant growth in vitro. Plantlets with 4-5 well-developed leaves with roots pre hardened in medium supplemented with 0.25 mg l(-1) each of PBZ and Triacontanol transferred to community pots filled with potting mixture of coco peat and tree fern (1:1) resulted in 72.3% survival ex vitro.