A novel method for regenerating plants from mesophyll protoplasts of Arabidopsis thaliana line WS.

A procedure has been developed for the successful regeneration of plants from mesophyll protoplasts of Arabidopsis thaliana line WS. The protocol is an improved version of that of Damm and Willmitzer (1988).The main changes in original procedure are as follows: (1) A mixture of Cellulase Y-C (0.5%) and Pectolyase Y-23 (0.05%) is used for the isolation of protoplasts. Use of these enzymes reduces the incubation time to 50 min. (2) α-Naphthaleneacetic acid is used as the auxin throughout cultures of protoplasts and calli. (3) Protoplasts and calli are incubated under dim white light (0.8-8 μW/cm(2)) during culture. With these modifications, we were able consistently to obtain regenerated shoots from about 70% of calli that had been transferred to shoot-forming medium even though the plating efficiency was rather low (about 0.5-1.5%).