Efficient in vitro culture protocols for propagating Phalaenopsis ‘Cool Breeze’

Abstract

Phalaenopsis orchids have high economic value in the floriculture industry as cut flowers and potted plants throughout the world. Plant tissue culture technology is being widely used for large scale plant multiplication of Phalaenopsis to feed into this industry. In order to increase the efficiency of this technology, four experiments were undertaken: Plantlet regeneration from seeds, nodes or leaves, and hardening of the regenerated plants. In the first experiment, seed germination was examined in three media (half MS, Chen and Vacin?Went) of which the Chen medium had the best result (83.4%) in comparison to the other two media. In the second experiment, nodes on the flower stalk were studied for their shoot formation potential to different concentrations of BA and NAA, The highest frequency of shoot regeneration was achieved on MS containing 4 mg/l BA and 1 mg/l NAA while in vitro derived leaves formed clusters of somatic embryos directly when cultured on MS containing TDZ at different concentrations (0.5, 1, 2 and 3 mg/l). The embryos turned green and developed into protocorm?like bodies after 7 weeks of culture followed by plantlet regeneration. The highest plantlet regeneration from the leaf?derived embryos was obtained from MS supplemented with 3 mg/l TDZ. Finally, regenerated plants from (seeds, nodal explants and leaves) were compared in two medium for hardening, regenerated plant from nodal explants showed the highest survival rate (100%) on the medium containing cocopeat, coal, industrial cartridge and the bites of yonolit (1 : 1 : 2 : 4).Plant Tissue Cult. & Biotech. 24(2): 191-203, 2014 (December)