| abstract |
SUMMARY OF THE INVENTION n the invention related to a method for producing a transgenic Brassica plant comprisingnthe steps of:n (a) isolating cotyledonary petioles from germinated seeds of a Brassica plant, (b) treating said petioles with an Agrobacterium solution, (c) transferring said treated petioles on a co-cultivation medium comprising at leastnone plant growth factor solidified with an agar, said agar characterized by an electroendosmosisnvalue (Mr) of below 0.5, a content of calcium ions of less then 1000nppm, and a content of magnesium ions of less then 500 ppm, and culturing saidnpetioles on said co-cultivation medium for about 1 to about 5 days, (d) transferring said co-cultivated petioles on a regeneration and selection mediumncomprising at least one plant growth factor, (e) cultivating said petioles on said co-cultivation and regeneration medium untilnshoots are induced and developed from said petioles and isolating said shootsnfrom said petioles, (f) transferring said isolated shoots on a shoot elongation and regeneration medium,nwherein the agar content in said medium is between about 0.3% and about 0.6%n(w/w) agar, and wherein said medium comprises between about 1% and 2.5%n(w/w) sucrose, (g) cultivating said isolated shoots on said shoot elongation and regeneration mediumnuntil said shoots have formed roots, and further regenerating the so derived plantletsninto mature plants, which comprise inserted into their genome a T-DNA comprisingna selectable marker gene and - optionally - an additional plant expressionncassette for an agronomically valuable trait. |