Plant Tissue Culture
       Plant tissue culture is used to create clones.
          – This is useful 
             To create pathogen free species
             Create crop species that have identical traits (e.g. 
              height)
             Save endangered species
       Somatic Fusion (Protoplast hybridisation) is 
         used to create new varieties.
          – Plant tissue culture is then used to grow the plant
                                                 
       Somatic Fusion
       Cells from two different plants are selected
       Cell wall is removed using cellulase and 
          pectinase
       Protoplasts are fused using either
          – Polyethylene Glycol
          – Electrical shock
       Protoplast is grown using tissue culture
                                                     
       Plant Tissue Culture
       Source of cell / tissue
           – Small pieces of tissue are taken from a plant.  
             These are called explants.
           – Protoplast from somatic fusion.
           – Plant cells / tissue have a long life span
       Suitable container
           – Anything sterile (the entire procedure must be 
             carried out under aseptic conditions).
                                                       
       Plant tissue culture cont…
       Growth Medium
           – Simple (can be liquid or solid) containing carbon 
             source, minerals salts, water, vitamins
           – Contains plant growth regulators to cause tissue 
             differentiation e.g.
              Cytokinins promote shoot development
              Auxins promote root development
                                                       
       Plant tissue culture cont…
        Events in Plant Tissue culture
           – Explant is removed and sterilised.
           – It is transferred to growth media
           – A mass of undifferentiated cells called the callus forms (this 
             occurs due to auxin and cytokinin concentrations being 
             balanced).
           – Tissue is transferred to growth media containing different 
             concentrations of growth regulators to promote shoot and 
             root production.
           – Tissue culture plants acclimatised in greenhouses.