A study was undertaken to develop a protoplast regeneration system for
pinellia. A yield of 19-29x10(5) protoplasts/g F. W. could be obtaine
d from cell suspension cultures incubated in a digestion enzyme soluti
on with 2% cellulase Onzuka R-10, 1% pectinase (Sigma), 0.01% pectolya
se Y23. K8P and modified MS media were used to culture protoplasts in:
a) liquid, b) liquid-solid double layer, or c) agarose embedded proto
plast culture. The former two were conducive to colony formation from
protoplast-derived cells. The frequency of cell division was about 8%
after 3 days in culture. Gradually adding fresh medium of lower osmoti
c pressure into the medium for protoplast culture favored cell divisio
n. Calli (1-2 mm in diameter) formed after 30-40 days in culture. The
calli transferred onto medium supplemented with KT (0.5 mg l(-1)) and
NAA (0.2 mg l(-1)) could regenerate plants after 40-50 days. Of 47 pla
ntlets transplanted into plots, 29 flowered and were fertile.