Investigations of different strategies for high frequency regeneration of Dendrobium malones ‘Victory’

Abstract

Regeneration of orchid, Dendrobium malones “Victory”, has been established by direct differentiation and through callus formation. With direct thin leaf section differentiation method, the number of protocorm like bodies (PLBs) formed from Thin Section (TS) explants obtained from a single leaf was 10 times more than that from a single whole leaf, in a short time period. This therefore suggested that the proliferation potential is distributed all along the seedling leaves and morphogenically competent cells were not limited in the basal ends or the tips of the leaves in TS of orchid leaf cultures. Full MS media supplemented with auxins/cytokinins either in single or in combination along with peptone, yeast extract, casein hydrolysate (each at 100 mg/l), banana powder (40 g/l), 15% coconut water and 2% sucrose have shown excellent results for high frequency regeneration in orchid cultures. In many higher plants, regenerating leaves responded by developing proliferative loci in some “Predetermined Regenerative” cells in the dermal layers by tissue culture methods.