Abstract: The Protoplasts were isolated enzymatically from tobacco crown gall tu- mors and its teratoma cells induced by Agrobecterium tumefaciens strain 702. Small colonies ware derived from them by incubating these protoplasts in mo- dified K and NT liquid media. T-DNA transformed-cell colonies were selected by transferring them onto NT medium without any phytohormone. Then single cell cloning strain of tobacco crown gall turnor 702c and its teratoma 702Tc have been established. Through being subcultured 15 times they all maintain their inherent characrts and contain nopaline. Being carried on root differentiatc experiment with this teratoma shoots, roots grow from a few of them and intact plants were obtained. Examining each parts of the plants separately, nopaline was present in all leaves and crown galls but was not detected in the roots. The roots perhaps grow from normal cells losing T-DNA. Its genes also perhaps do not express.

Key words: single, cell, clonging, tobacco, tumour