An efficient genetically stable regeneration protocol with increased
phytochemical production has been established for
Dendrobium nobile, a highly prized orchid for its economic and
medicinal importance. Protocorm like bodies (PLBs) were induced
from the pseudostem segments using thidiazuron (TDZ; 1.5 mg/l),
by-passing the conventional auxin–cytokinin complement approach
for plant regeneration. Although, PLB induction was
observed at higher concentrations of TDZ, plantlet regeneration
from those PLBs was affected adversely. The best rooting (5.41
roots/shoot) was achieved in MS medium with 1.5 mg/l TDZ and
0.25% activated charcoal. Plantlets were successfully transferred to
a greenhouse with a survival rate of 84.3%, exhibiting normal
development. Genetic stability of the regenerated plants was
investigated using randomly amplified polymorphic DNA (RAPD)
and start codon targeted (SCoT) polymorphism markers which
detected 97% of genetic fidelity among the regenerants. The PIC
values of RAPD and SCoT primers were recorded to be 0.92 and 0.76
and their Rp values ranged between 3.66 and 10, and 4 and 12
respectively. The amplification products of the regenerated plants
showed similar banding patterns to that of the mother plant thus
demonstrating the homogeneity of the micropropagated plants. A
comparative phytochemical analysis among the mother and the
micropropagated plants showed a higher yield of secondary
metabolites. The regeneration protocol developed in this study