Clonal propagation of fruit trees and other plant species through tissue culture is based on the concept of cell totipotency first expressed by Virchow in 1858 (54) which derived from the cell theory that Schleiden proposed in 1838 (46). Technical problems made it impossible to put these ideas into practice, and more than a century passed before plants could be cultured in vitro. Plant tissue culture developed with the improvement of technology; thus, it has not been a revolution in theory but an evolution of techniques. The origins of plant tissue culture trace to studies by Haberlandt (14), who aseptically cultured single cells on a liquid medium supplemented with sugar. The cells remained alive, but were unable to proliferate.