Effect of edible sugar on in vitro growth and organogenesis of Dendrobium bigibbum x Dendrobium Thailand Black

Abstract

The most popular propagation method of Dendrobium is in vitro micropropagation. However, using laboratory-grade sucrose as the carbon source in micropropagation is expensive for small- scale producers. Present study is aimed to assess the performance of edible sugar as an alternative carbon source to develop an effective, low-cost medium. Protocorm like bodies (PLBs) and plantlets of Dendrobium hybrid (Dendrobium bigibbum x Dendrobium Thailand Black) were cultured on basal MS medium containing different concentrations of sugar; 0.0, 15.0, 30.0, 45.0, 60.0, 75.0 and 90.0 g/L, (T1-T7). A modified MS medium (T8) containing sugar (30.0 g/L), BAP (2.5 mg/L) and NAA (0.5 mg/L) was also used to determine whether there is a comparable effect of sugar individually and when combined with plant growth regulators (PGRs). Growth performance was evaluated in regular intervals. MS medium containing sugar (45.0 g/L) was identified as the best medium for the growth and organogenesis of PLBs resulting in the highest weight accumulation of 20.31 g and 35 plantlets regeneration from 1.00 g of PLBs after two months of incubation. MS medium supplemented with 60.0 g/L of sugar was identified as the most successful medium for the plantlet growth with 17 of mean leaf generation, 33 of mean root generation and an average root length increment of 1.5 cm after four months of incubation. In conclusion, edible sugar can be recommended to use as a sucrose supplement for a cost-effective medium to promote successful in vitro growth and development of the Dendrobium hybrid even with the absence of PGRs.