Optimization of gus gene transferring to Begonia soli-mutata

Begonias are popular ornamental plants in the world so introducing of various forms of this plant is very important. Nowadays plant modification through biotechnology and genetic engineering for production of new genotypes with varied forms is highlighted in this genus. So optimization of regeneration in in vitro culture condition and gene transferring is in priority to provide a suitable condition for gene transferring in this plant specially those responsible in flower color.
 
In the first step, thin cell layer (TCL) explants from petioles of B. soli-mutata were assayed in MS medium containing Kin or TDZ (0.2, 1 and 2 mg/l) in combination with NAA (0 and 0.2 mg/l). For co-culturing of petiole TCL explants with Agrobacterium tumefacians strain LBA4404 containing GUS and NPTII genes MS medium supplemented with 1 mg/l Kin and 0.2 mg/l NAA was used. Transformed plantlets were confirmed by PCR and Gus assay test.
 
Based on the regeneration results, Kin was better than TDZ, also adding NAA to the medium has positive effect on both of cytokinins. In transformation process, out of 2000 explants which infected with Agrobacterium, after 4 months of culture only 17 plantlets were adopted. Of these 17 plantlets, only 7 plantlets were confirmed by Gus assay test and PCR as transgenic plants.
 
The result showed in this species transformation percentage is low and optimization of transformation condition is important.