Chapter 17 Tissue Culture: Micropropagation 443
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Review and Assessment
CHAPTER
17
Chapter Summary
• Tissue culture is used to grow or maintain plants in a nutrient medium
under sterile conditions. Micropropagation, also sometimes referred to
as tissue culture, is an asexual propagation method in which plants are
manipulated on a cellular level.
• Since the 1970s, many advances have been made in tissue culture.
Current techniques are possible because of the stabilization of tissue
culture medium made by Murashige and Skoog in 1962.
• Micropropagation offers benefi ts or advantages, such as providing
identical plant material at the quickest rate of replication and providing a
breeding method for plants that are not usually compatible.
• Micropropagation has some disadvantages. It is a costly endeavor that
can only be achieved through sterile techniques performed by skilled
technicians.
• When using micropropagation techniques, it is essential to have a clean
room with a laminar fl ow hood to reduce contamination. Scalpels,
forceps, and tweezers must be made sterile through the use of bleach
solutions, ethanol, isopropyl alcohol, or fl aming.
• Growth media are combinations of chemicals, vitamins, nutrients,
growth regulators (hormones), and water used to grow and sustain cells
in vitro. The growth medium must be sterile and can be a liquid or a gel.
• There are fi ve stages of micropropagation. Stage 0 includes selection
and cultivation of stock plants. Stage 1 includes establishing an aseptic
environment, sterilizing explants, and transferring explants to an
in vitro culture. Stage 2 involves multiplication of plantlets. Stage 3
involves rooting plants in preparation for transplanting. Stage 4 involves
hardening off plants.
• Micropropagation is used in forestry, agronomy, and horticulture.
• The process of micropropagation, which manipulates plants at a cellular
level, shows great promise. Micropropagation can be used to create new
and improved fruits, vegetables, and ornamental plants.
• Several technical careers are available in micropropagation, including
laboratory technician or cryopreservation scientist.