Abstract: The influences of enzyme combination,osmoticum,and suspension cell growth phase on both protoplast yield and protoplast viability were investigated with embryonal suspension cell from mature zygotic as materials of isolation protoplast.The results show that protoplast yield and protoplast viability of suspension cells on linear phase are the highest under the enzyme combination cellulase RS 1%+cellulase R-10 2.5%+pectolyase Y-23 0.2% and osmoticum mannital.After protoplast were cultured on DCR medium,the first division of protoplast appeared on 6th day,embryonic cell mass appeared on 4th week,embryonal suspensor mass appeared on 8th week,and somatic embryo with primary cotyledonary appeared on 16th week.

Key words: Pinus taeda L., Protoplast, Embryonal suspensor mass