Perhaps the earliest step towards plant tissue culture was made by Henri-LousDuhumel du Monceau in 1756, who during studies on wound healing in plants,observed callus formation. Extensive microscopic studies led to the independentand almost simultaneous development of the cell theory by Schleiden (1838)and Schwann (1839). Scheilden and Schwann put forward the co-calledtotipotency theory, which states that cells are autonomic, and in principle, arecapable of regenerating to give a complete plant. Their theory was in fact thefoundation of plant cell and tissue culture.