This study for the first time was aimed at developing a protocol for the genetic transformation of embryogenic tissue derived from the vegetative shoot apices of mature trees of P. roxburghii. This was achieved via the introduction of a bar-GUS cassette under the control of the ubiquitin promoter, through biolistic transfer. Expression of positive histochemical GUS activity (31%) in the bombarded embryogenic tissue was observed. PCR analysis of bar transgenes (54%) transformation efficiency indicated successful genetic modifications of P. roxburghii embryogenic tissue by the pAHC25 plasmid. This is the first successful report of genetic transformation in P. roxburghii using embryogenic tissue derived from the mature trees indicating that Chir pine is amenable to gene transfer.
