In Vitro Propagation of Lilium longiflorum Bulbs Using NAA and BAP Plant Growth Regulator Treatment

Abstract

Lily (Lilium longiflorum) is a perennial herbaceous plant with white trumpet-shaped flowers, fragrant and bulbous. In vitro culture through bulbs is one of way propagation of lily plants, but it requires a long time and only produces limited plants. In vitro propagation is a very promising technique for plant propagation because it can produce a lot of plant seeds in a short time. Bulbs are one of the fastest explants for growing shoots in lilies, but it is not known for certain which cuts of explants from bulb scales are best for multiplying in vitro. This study aims to determine the effect of lily bulb explants and the concentration of NAA and BAP growth regulators on the growth of lily bulb explants. The best results were obtained on the base and middle cuts explant of bulb scales compared to the tip cuts explant ones. The best results of the growing percentage, the number of shoots and the best growing time are shown in the combination treatment of growth regulator 1 mg L−1 NAA and 1 mg L−1 BAP. The optimum results on the number of micro bulbs were found in the treatment of growth regulators 0.5 mg L−1 NAA and 1 mg L−1 BAP. The best results of the average time formed micro bulb was in the treatment of 1 mg L−1 NAA and BAP with middle explant cuts, and treatment concentrations of 0.5 mg L−1 NAA and BAP in the base explant section. The base and middle bulb explants are able to regenerate or grow higher shoots. This is caused by the presence of endogenous natural auxin and the spread of auxin in plant parts not in the same amount. Therefore when added to the exogenous growth regulator such as auxin or cytokines to culture media will further trigger the formation of micro tubers more quickly,. It can increase the concentration of endogenous growth regulators in cells, help growing process and developing tissue.   Keywords: Bulb, lily, micro bulbs, in vitro, shoots