clones in plants

• tissue culture


  • growing new tissues, organs or plants from certain tissues cut from from sample plants
• micro propagation


  • growing large numbers of plants from meristem tissue taken from a sample plant
• cuttings


  • to make a cutting a stem is cut between two leaf joints (nodes)
  • the cut end of the stem is then placed in soil where new roots will grow from the tissues in the stem
  • dipping the stem in rooting hormone helps to stimulate root growth
  • this produces large numbers of plants quickly
  • cuttings can also be made from roots, dormant twigs and leaves.
• micro propagation

  1. cells taken from shoot (called explant)
  2. cells sterilised before being placed onto nutrient medium
  3. explants placed on sterile growth medium. Forms a callus cultured divided to produce lots of small clumps or undifferentiated cells
  4. transferred to a new agar medium - plantlets grow
  5. plantlets are transferred into compost
• Advantages

  • Rapid compared to growing from seeds
  • Disease free plants
  • Increase number of rare plants
  • Large numbers of seedless plants
  • Naturally infertile plants can be grown
• Disadvantages

  • Monoculture - genetically identical - susceptible to same diseases
  • Expensive and requires skilled workers
  • Explains and plantlets are vulnerable to mould during the process
  • if source materials infected with a virus, all new plants are infected