In vitro regeneration and Agrobacterium-mediated genetic transformation of Dragon's Head plant (Lallemantia iberica).

ABSTRACT

Dragon's head plant (Lallemantia iberica), is a flowering species belongs to the mint family (Lamiaceae). The species contains valuable essential oils, mucilage and oil which are used in pharmaceutical and food industries. Tissue culture is a feasible strategy to attain large-scale production of plantlets with a huge potential to produce plants with superior quality. The objective of this study was to develop a simple and efficient method for regeneration and transformation of L. iberica. To reach this goal, the regeneration ability of various explants including leaf, cotyledonary node, hypocotyl and cotyledon segments was investigated in MS medium supplemented with diverse concentrations of NAA (Naphthalene acetic acid) and BAP (6-Benzyl Amino Purine). According to the results, cotyledonary nodes showed the best regeneration response. The maximum rate of regeneration (and number of induced shoots was achieved in 1 mg l-1 BAP in combination with 0.05 mg l-1 NAA from the cotyledonary nodes. Additionally, through the optimized regeneration technique Agrobacterium-mediated transformation of L. iberica was successfully accomplished. Gene transfer was assessed on leaf samples from regenerated plantlets under a fluorescent microscope to detect the GFP signals. Moreover, transgene integration and its expression were confirmed by PCR and RT-PCR analysis, respectively. The establishment of these efficient regeneration and genetic transformation methods paved the way for further application such as plant improvement, functional analysis and gene editing.