In experiment 2, the age of young
plantlets
of Dendrobium Sonia ‘Earsakul’ at 6
months of culture (leaf length about 1.0 cm measured
from the axillary bud) was cultured in vitro to induce
PLBs formation and regeneration. Two weeks before
the experiments, the PLBs and young plantlet were
cultured on Vacin and Went (1949) (VW) solid
medium, in which pH was adjusted to 5.5 and with
no PRGs added.