Plant Cloning

Question 0

What are the advantages of using plant cloning in agriculture?

Answer 0

• desirable genetic characteristics are always passed on to clones e.g. High yield
• plants that are sterile can be reproduced e.g. Banana
• plants that take a long time to produce seeds can be reproduced quickly

Question 1

Describe the production of artificial clones of plants from tissue culture

Answer 1

• a small piece of tissue is taken from the plant to be cloned (explant)
• the explant is then placed on a nutrient growth medium
• cells in the tissue divide but do not differentiate, instead they form a mass of undifferentiated cells (callus)
• after a few weeks, single callus cells can be removed from the mass and placed on a growing medium containing plant hormones that encourage shoot growth
• after a further few weeks, the growing shoots are transferred onto a different growing medium containing different hormone concentrations that encourages root growth
• the growing plants are then transferred to a greenhouse to be acclimatised and grown further before they are planted outside

Question 2

What are the disadvantages of using plant cloning in agriculture?

Answer 2

• undesirable genetic characteristics are passed on to clones
• lack of genetic variability (single disease could kill all)
• production costs are high

Question 3

How do elm trees produce natural clones by vegetative propagation?

Answer 3

• a sucker is a shoot that grows from the shallow roots of an elm tree
• suckers grow from sucker buds that are scattered around the trees root system, these buds are usually dormant
• during time of stress or when a tree is dying the buds are activated and suckers begin to form
• suckers can pop up metres away from the parent tree, which can help to avoid the stress that triggered their growth
• they eventually form completely separate trees - clones of the tree that the suckers grew from