Schematic representation of the T-DNA region of binary vectors used for mustard transformations. A pBKhgASAL showing ASAL gene under CaMV35S promoter and hpt gene cassette flanked by two lox sequences. B pBK16.2 showing the cre gene under CaMV35S promoter, also containing bar gene as selection marker; the respective restriction endonuclease sites are indicated. A1/B1, A2/B2 and A3/B3 indicate the primer sequences for ASAL, cre and hpt genes, respectively. 5′ → 3′: orientation of lox sequences. LB: T-DNA left border; RB: T-DNA right border.