Plant regeneration from mesophyll protoplast culture of cabbage (Brassica oleracea var 'capitata').

Protoplasts were enzymatically isolated from the first leaves of cabbage (Brassica oleracea var 'capitata', F1 hybrid 'Baochun'). Sustained cell division and somatic embryogenesis were obtained after culturing the protoplasts in modified liquid DPD medium supplemented with CaCl2 · 2H2O 800 mg/l, 2,4-D 0.5 mg/l, kinetin 1 mg/l, 0.3 M mannitol and sucrose 20 g/l. Upon transferring cell colonies onto a modified Murashige and Skoog (MS) agar medium, small calli were gradually formed. Callus proliferated on MS medium supplemented with hormone combinations of 2,4-D 0.1-0.5 mg/l and kinetin 3-4 mg/l. Multiple shoots were induced on differentiation medium supplemented with 3 mg/l of kinetin and 0.1 mg/l of gibberellic acid GA3. After transferring differentiated shoots onto MS medium supplemented with indoleacetic acid (IAA), kinetin, GA3 at 0.1 mg/l each and 500 mg/l of N.Z. amine, intact plants were eventually produced.