Optimization of 2,4-D and Cytokinin Combination for the Growth of Vanda tricolor in Solid and Liquid Medium

Abstract

Vanda tricolor orchid is an endemic plant. Yogyakarta is one of the distribution areas of the V. tricolor Lindl Suavis varieties in Indonesia, besides East Java, West Java, Bali and Sulawesi. The existence of the V. tricolor orchid on the slopes of Mount Merapi in Yogyakarta is threatened with extinction due to eruption and exploitation by humans. The existence of the diminishing V. tricolor orchid encourages efforts to conserve V. tricolor orchids into their natural habitat through conservation. One of the conservations carried out through in vitro propagation is somatic embryogenesis. The aim of this study is to determine the best combination of 2,4-D and cytokinin in solid and liquid medium for the growth of pro embryo V. tricolor. This research is a laboratory experiment using a single factor experimental method arranged in a completely randomized design. The treatments tested were a combination of 2,4-D (0, 2, 4 mg L-1), cytokinin (Benzyl Amino Purine and Thidiazuron, 0 and 0.5 mg L-1) and the type of medium (solid and liquid). The basic medium used is New Dogashima Medium (NDM). Activated charcoal 0.2 g L-1 and Plant Preservative Mixture 0.5 ml L-1 were added to all treatments. The observed parameters included: Percentage of viable, contaminated and vitrified explants (%), number of leaves, number of pro embryos and number of roots. The results showed that treatment of New Dogashima Liquid medium without 2,4-D with the addition of 0.5 mg L-1 Thidiazuron was chosen as the best medium for the growth of V. tricolor shoots.