Fig. 1

Ubi:OsGA2ox6 transformation vector and comparisons of different propagation types of GA2ox6-OX transgenic lines at various growth stages. a Schematic diagram of the Ubi:OsGA2ox6 transformation vector. The target gene OsGA2ox6 (yellow box) driven by the ZmUbi promoter (blue arrow), hygromycin phosphotransferase (Hpt) and GUS genes driven by the 35S promoter (green arrows) in their relative scale within the left border (LB) and right border (RB) of T-DNA are shown. The primers (Hpt-F & -R and ZmUbi-F & OsGA2ox6-R) used for confirming vector integration (genomic DNA PCR) and the primers (OsGA2ox6-F & -R) used for gene expression analysis (RT-PCR) as well as the sizes in bp of their PCR products are indicated. b Protocorm-like bodies (PLBs) of Phalaenopsis Sogo Yukidian ‘SPM313’ used for transformation. c Three surviving transgenic PLBs 6 months after transformation and selection. d–g Growth of propagation type A (d, f) and type B (e, g) from the GA2ox6-OX transgenic line 1 month (d, e) and 3 months (F, G) after subculture. A group of three PLBs is shown. h Examples of an NT (left) and a GA2ox6-OX transgenic (right) plantlet growing multiple leaves and roots approximately 10 months after transformation. i Close-up view of a transgenic plantlet growing approximately 12 months after transformation. j–k Example of the mother PLBs from NT (j) and GA2ox6-OX transgenic (k) lines used for propagation. l–m Clonal propagation of NT and GA2ox6-OX transgenic PLBs compared in parallel. The PLBs from NT (l) and GA2ox6-OX (m) lines were dissected horizontally to expose their surrounding epidermal cells in order to generate and propagate new PLBs. n–o Growth of many PLBs three months after subculture for NT (n) and GA2ox6-OX (o) lines