We have successfully developed a method to induce
early in vitro flowering of the self-pollinated seedlings
of a tropical orchid hybrid, Dendrobium Madame Thong-In.
Transition of vegetative shoot apical meristem to inflorescence
meristem was observed when young protocorms were
cultured in modified KC liquid medium. In contrast, protocorms
cultured on Gelrite-solidified medium only produced
axillary shoots and roots. CW was required to trigger the
transitional shoot apical meristem and BA enhanced inflorescence
stalk initiation and flower bud formation. However,
normal flower development was deformed in liquid medium
but developed fully upon transferring to two-layered (liquid
over Gelrite-solidified) medium. Under optimal condition,
in vitro flowering was observed about 5 months after seed
sowing. Segregation of flower colours was observed in these
seedlings and seedpods formed upon artificial pollination of
the in vitro flowers.