Somatic Embryogenesis of Lilium from Microbulb Transverse Thin Cell Layers

Abstract

A reliable somatic embryogenesis protocol is a prerequisite for application of other plant biotechniques.Several protocols were reported for genus Lilium, with variable success. Between them, transverse ThinCell Layers (tTCL) were used efficiently to induce indirect somatic embryogenesis of Lilium. Somaticembryogenesis potential is dependent on the genotype, explant, and culture medium composition,especially as for plant growth regulators and environmental conditions. Usually, the process comprisesthree phases: embryogenic callus induction, embryogenic callus proliferation and somatic embryogermination. Somatic embryo germination can be achieved in light or dark. In the first case, completeplantlets are formed, with green leaves and pseudobulb in the base. In darkness, microbulbs are formedfrom single somatic embryos or clusters. A last phase of microbulb enlargement allows plantlets ormicrobulbs to increase their biomass. These enlarged microbulbs do not need special acclimatizationconditions when transferred to soil and quickly produce sturdy plants. This chapter describes a protocolfor somatic embryogenesis of Lilium using tTCL from microbulbs.