In Vitro Conservation and Propagation of Dendrobium signatum Rchb.f. Collected from Chattrakarn National Park, Phitsanulok.

Abstract

Three Ueng Kham Kew orchids (Dendrobium signatum Rchb.f.) growing on
Plerocapus sp. and Dipterocarpus sp. at the height 8-15 meters have been found on the 3-kmlength
natural route survey of Chattrakan Waterfall National Park. Cultivating the seeds with Vacin
and Went (1949) and studying the effect of hormone NAA at concentrations of 0.0, 0.5, 1.0, 1.5,
2 .0ppm and hormone BA at concentrations of 0.0, 0.5, 1.0, 1.5, 2.0 ppm on the growth of the
orchids for 4 months was carried out. It was found that an application of 1.5 ppm NAA and
0.5 ppm BA showed the maximum number of buds (5.70). Ueng kham kew orchids showed the
highest number of leaves (16.50), height (5.47cm) and number of roots (15) when treated with 1
ppm NAA and 0.5 ppm BA. The concentration of 2 ppm NAA without BA yielded root-length of
6.05 cm. In addition, the study of appropriate orchid-supporters shows that the orchids grown on
coconut shell have the highest survival percentage at 85 %.

Keywords: Dendrobium signatum Rchb.f., Tissue culture, Auxin, Cytocynin