Effects of plant growth regulators and different growth media on Cymbidium finlaysonianum var. alba in vitro propagation

Abstract

This study aimed to determine the suitable medium for in vitro culture of Cymbidium finlaysonianum var. alba, a valuable native orchid species in Vietnam. The effects of plant growth medium strength (Murashige and Skoog medium, MS) and the addition of plant growth regulators, commercial fertilizer, organic additives and activated charcoal (AC) on in vitro shoot culture of C. finlaysonianum var. alba were investigated. The results showed that, after culture for 2 months, the best medium for shoot multiplication from shoot tip explants was MS containing 1.0 mg/L Benzyl adenine (BA) and 0.5 mg/L α-naphthalene acetic acid (NAA) with a high multiplication rate (8.98 shoots/explant). The half-strength macro-nutrient MS medium (½ MS) augmented with 2.5 mL/L foliar fertilizer Growmore Humer (FFGH) and 60 g/L banana extract was found to be effective for growth with 5.81 cm shoot height, 4.80 leaves/shoot and 3.22 roots/shoot, compared to other media. The ½ MS medium supplemented 1.0 mg/L NAA and 1.0 g/L AC was appropriate for in vitro root formation with 4.87 roots/shoot and 3.63 cm root length. Plantlets were easily acclimatized in ex vitro conditions to create complete plantlet.