Effects of Explant Source and Dark-preconditioning on Adventitious Bud Formation in Neofinetia falcata H. H. Hu in vitro

Tissue culture methods were investigated for propagation of the epiphytic orchid Neofinetia falcata H. H. Hu. The protocorms were divided into upper and lower portions and cultured. An average of 1.0–1.7 plantlets per explant were derived from upper portions which had survived at frequencies at 10–30%. Plantlets that developed from protocorms were cultured to increase the survival rate. All explants derived from upper portions of the plantlets survived, but explants from lower portions of plantlets did not. Explants derived from dark-preconditioned plantlets showed multiple bud formation when grown on medium containing 0.44 μM N6-benzyladenine (BA) and 5.37 μM α-naphthaleneacetic acid (NAA). Leaf explants derived from dark-preconditioned plantlets produced adventitious buds most efficiently when cultured in medium containing 0.44 μM BA and 5.37 μM NAA. These results suggest that the most suitable culture materials for bud formation in N. falcata are the upper portion of plantlets and the leaves of dark-preconditioned plantlets.