Micropropagation of Phalaenopsis circus via direct organogenesis using protocorm-like bodies explant

Phalaenopsis orchid has high economic value in the floriculture industry and is one of the most popular orchids in the world. Tissue culture techniques makes it possible to propagate and conserve this species. The aim of the present study was to evaluate the effect of different concentrations of two plant growth regulators (PGRs), namely N-Phenyl-N′-1,2,3-thiadiazol-5-yl-urea (TDZ) and 2,4-dichlorophenoxyacetic acid (2,4-D), alone and in combination with each other, on the number of protocorm-like bodies (PLBs), leaves, and roots, along with leaf and root lengths of micropropagated Phalaenopsis circus using leaf explants through organogenesis method. Also, correlations between these traits in the Phalaenopsis circus plantlets under study were calculated. Plantlets produced from PLBs were cultured on MS (Murashige and Skoog) basal media enriched with various levels and combinations of TDZ and 2,4-D. The optimal concentrations of the PGRs for micropropagation of Phalaenopsis circus are reported and discussed. The maximum number of PLBs (75.00) was obtained on the medium enriched with 1.00 mg l–1 2,4-D. The highest length of leaf (5.23 cm) was calculated on the medium enriched with 2.00 mg l–1 2,4-D. Concentration of 1.00 mg l–1 TDZ induced the maximum number (6.07) of leaf. The longest root length (4.15 cm) and the largest number of root (4.93) was obtained in medium augmented with 2.00 mg l–1 2,4-D.