PROTOPLAST FUSION OF CATHARANTHUS-ROSEUS CELLS BY ELECTROFUSION OF CHEMICALLY-AGGLUTINATED PROTOPLASTS

Mesophyll derived protoplasts of Catharanthus roseus cv. Little pinkie were fused w th protoplasts derived from an habituated cell line of C . roseus. Polyethylene glycol was used as agglutinating agent while fu sions were induced by square pulses. Best results were obtained by fus ing protoplasts from primary leaves with those from three-day-old cell cultures. Adding calcium ions considerably enhanced heterofusion rate . Good cell viabilities indicated that this fusion process was not cyt otoxic. The heterofusion frequency was up to 10% or more. Most of the heterokaryons were able to regenerate their cell walls and underwent d ivision.