micropropogation

• • tissue culture is a process which very small ( micro ) pieces of plants ( tissue ) are grown ( cultured )
  • bc theyre initially grown in petri dishes on nutrient agar they are grown in vitro - outside a living organism
• how to micro propogate plants in vitro:

  1. cells are scraped from the parent plant ( explants)
  2. the surface of explants r sterilised using disinfectant followed by a rinse with sterile water
  3. transferred to a sterile petri dish containing sterile nutrient agar which encourages explant cell to grow and divide into small masses of cells ( callus )
  4. each callus is transferred to a fresh growth medium that contains a range of plant growth regulators ( hormones ) which causes it to develop roots, stems, leaves forming a plantlet which can be transferred to individual potting trays and dev into plants
• Label

  A) explants

  B) parent

  C) sterilised

  D) sterilised

  E) soaking

  F) disinfectant

  G) rinsed

  H) sterile water

  I) light

  J) cotton

  K) bacteria

  L) gas

  M) callus

  N) divide

  O) transferring

  P) regulators

  Q) stems

  R) roots

  S) leaves

  T) plantlet

  U) soil

  
• COMMERCIAL USE: advantage

  • genetically identical so allows a variety of a plant with desirable characteristics to be produced cheaply, greater yield (per square metre), quickly, any time of year, identical and disease free / resistant
  • producing enough plants so a country dont need to import it from other countries which might bring diseases
  • preserving rare species
• COMMERCIAL USE: disadvantage

  • trained personnel and sterile laboratory required
  • genetically identical - all vulnerable to the same diseases and pests (less able to adapt to environmental change)