In vitro propagation of Vanilla planifolia, a tropical orchid

A simple and efficient micropropagation protocol was developed for Vanilla planifolia using shoot tip and nodal segments as explants, The explants wer e cultured in MS basal medium with 1 mg/l BAP for 10 weeks and subcultured onto fresh medium every 4 weeks. The proliferating clusters were cultured i n N69 basal medium with BAP (0.5 mg/l) + d-biotin (0.05 mg/l) + folic acid (0.5 mg/l) and 2% sucrose for elongation of shoots, formation of root initi als and further proliferation of axillary shoots. Separation and culturing of elongated shoots in fresh medium for 2 to 3 weeks yielded 7 to 8 cm long plantlets, which were acclimatized in polytunnels. The clusters of shoots, which did not elongate, served as a continuous source of explants for mult iplication.