Micropropagation

Question 1

Acclimatization

Answer 1

• the preferred term for the process of gradually moving tissue culture-grown plantlets to open-air conditions
• gradually reducing humidity and increasing light levels
• the leaves in in vitro have less cuticle wax and different shaped stomata
• the roots in in vitro have reduced structure and increased cell size and are not able to fully function as normal roots

Question 2

Disinfestation

Answer 2

• chemical removal of surface contaminants that would otherwise grow in the tissue culture environment and kill the explant
• external contaminants are literally everywhere - in the air, on the surfaces of plants, tables, hands, and etc.
• use stock plants as sorce of explants
• explants disinfested with brief alcohol treatment
• followed by 10-15 minutes in agitated bleach solution
• if not inproperly disinfected, will lead to microbial growth on the medium and the explant

Question 3

Ex vitro

Answer 3

• growth and development outside the tissue culture environment

Question 4

Explant

Answer 4

• a piece of tissue used to initiate a tissue culture
• the most commonly used explants for micropropagation include stem and leaf sections
• sometimes flower parts, roots, and seed tissues have all been used
• the piece of the plant (propagule) used to initiate the micropropropagation or tissue culture process

Question 5

In vitro

Answer 5

• the culture of plant cells or organs in culture vessels (like test tubes) under controlled environment and nutritive growth medium
• production in a test tube or other similar vessel where culture conditions and medium are controlled for optimum growth during tissue culture
• growth and development in the tissue culture environment

Question 6

Microcuttings

Answer 6

• microshoots used as small cuttings induced to regenerate roots and eventually a plantlet.
• single microshoots moved to a medium to induce rooting
• can be rooted either in virto or ex vitro
  
  • microshoots = shoots developed during tissue culture

Question 7

Micropropagation: Advantages

Answer 7

• the natural rate of increase is slow
• new cultivars with high commercial demand
• cultivars with high market value
• plants that are difficult to propagate
• conservation of endangered species

Question 8

Micropropagation: Disadvantages

Answer 8

• expensive with high labor costs
• requires sophisticated facilities
• trained personal
• specialized techniques

Question 9

Stabilization

Answer 9

• is when an explant has been established in vitro and has grown new shoots that are ready to subculture

Question 10

Subculture

Answer 10

• the process of dividing stems or tissue from a tissue culture into smaller pieces and then transferring them to a fresh medium to multiply the tissue culture
• the act of subdividing the developing explants into smaller pieces and moving them to a new medium as occurs in the multiplication stage of micropropagation

Question 11

Transfer

Answer 11

• moving the entire culture to a new medium. there is no subdivision, as there is in subculturing
• done in sterile environment, under laminar air flow hood

Question 12

Totipotent

Answer 12

• the concept that a single cell has the genetic program to grow into an entire plant