Abstract: The paper reports that growth of isolated Petunia hybrida mesophyll protoplasts cultured in eight different media was compared. The protoplasts underwent cell wall regeneration, followed by repeated cell division and developed into colonis in all used media. Calli were obtained in six kinds of these media. Both medium G composed by ourseleves and modified medium K are excellent. Their plating efficiency was raised to 56% and 70% respectively. Effect of some plant hormones on growth and differentiation of the callus was tested. Some hormone combination effected greatly on growth of the callus, Roots had differentiated from the cqlli in some media containing hormones.

Key words: better, media, culturing, mesophyll, hybrida