As part of the development of a transformation protocol for 'Bramley's' seedling apple ('Bramley'), a leaf disc regeneration system had to be developed. It was found that 'Bramley' did not respond adequately to the 'Greensleeves' protocol. Consequently a range of modifications to the 'Greensleeves' protocol was investigated. For shoot multiplication, the concentrations of IBA, BAP, GA(3), and gelling agents were investigated and it was found that the optimum shoot multiplication media consisted of MS salts, 30 g l(-1) sucrose, 2 mg l(-1) BAP, 0.1 mg l(-1) IBA and 6 g F, Noble Agar (pH 5.7). For shoot regeneration from leaf discs, a range of BAP and TDZ concentrations was examined in addition to the phytotoxicity of cefotaxime and kanamycin. Whilst 'Greensleeves' responded in line with published data, 'Bramley' produced significantly fewer shoots. 'Bramley' shoots were obtained from 5 mg l(-1) BAP and I mg l(-1) NAA. TDZ did not increase regeneration significantly. 100 mg l(-1) cefotaxime and 5 mg l(-1) kanamycin gave a good level of selection and the elimination of Agrobacterium without inhibition of regeneration.
