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Plant cloning
Content
Definition
Development
Benefits
Benefits
Procedure
Dangers
Dangers
Future
Examples
Examples
Definition
deliberate, directed reproduction of plants using seeds
or spores (sexual propagation), or using vegetative
cells, tissues, or organs (asexual reproduction)
 is effected in nature chiefly sexually by the seed and the
spore, less often by rhizomes
 vegetative means include cutting, layering, grafting,
tissue culture, and division of the roots and of the tubers
 most farm and garden crops are propagated by seed
 but some plants will not breed true from seed and must
be propagated by various vegetative methods
Sexual propagation
Sexual propagation of plants (seed)
 involves the exchange of genetic material between parents to produce a new
generation
Advantages:
 usually the only method of producing new varieties or cultivars
 often the cheapest and easiest method of producing large numbers of plants
 can be a way to avoid certain diseases
 may be the only way to propagate some species
 seeds and spores are used for reproduction
 seeds are typically produced from sexual reproduction within a species, since
genetic recombination has occurred plants grown from seed may have different
characteristics to its parents
 some plant species do not produce seed until they reach maturity
 seed can be difficult to acquire and some plants do not produce seed at all
Asexual propagation
Asexual propagation of plants (vegetative propagation)
 does not involve exchange of genetic material ¡ú produces plants that are identical
to a single parent
 accomplished by taking cuttings, by grafting or budding, by layering, by division of
plants, or by separation of specialized structures such as tubers, rhizomes, or bulbs
 used in agriculture, in scientific research, professional and recreational gardening
Advantages over seed propagation:
 retains the genetic constitution of the plant type almost completely
 faster than seed propagation
 may allow elimination of the nonfruiting, juvenile phase of the plant's life
 preserves unique, productive or esthetically desirable plant forms
 allows plants with roots well adapted for growth on poor soils to be combined with
tops that produce superior fruits, nuts or other products
Procedure
Tissue culture
propagation
 1.step:
• Explants
• Tissue is placed in
tissue culture
container
• Sterilization
• Agar (mixture of
nutrients, sugars,
vitamins, hormones)
 rapid growth of
tissue
Procedure
 2.step:
multiplication
• starts to grow
• production of new
plants
 3. step:
rapid multiplication
• development starts
• new plants can be
removed into other
tissue culture
containers
 thousands of new
plants can be
produced
Procedure
Advantages
 4.step:
• when plants are
large enough 
removed into
acclimation container
 production of exact
copies of plants
 quickly produce
mature plants
 5. step:
 production of
multiples of plants in
the absence of seeds
• Transplantation into
pots
 reduced chances of
transmitting diseases
• growth in
greenhouse
Asexual
reproduction
 in-vitro culture
Development
 Put on market in
early 1990s
 widely spread in
the US
 first GM food:
tomatoe
 Most common:
soybean, corn,
canola, cotton seed
oil
 Many
controversies
 safety protocol in
Europe  labelling
Benefits
 plants can be designed to be resistant to herbicides
 gm provides crop failures
 new plants can be created very rapidly (faster than by nature)
and the reproduction is cheaper
 cloning can rid plants of harmful viruses and diseases
 plants which for some reasons can’t produce seeds (for
example cultivated bananas) would not survive without cloning
 greater uniformity of the cloned plants (good for landscape
designers, hedges, rows of trees etc.)
 no wasting of resources on plants with a poor yield: optimising
the harvest results
Dangers
 temporary control of nature is not possible
 results are not predictable, unwanted results are not
necessarily containable or reversible
 genes can be transported to wild plants superweeds 
potentially disturbing the balance of nature
 loss of gene diversity  thus all these clones will very likely catch the same diseases
 unpredictable behavior: genes replicate themselves out of control in the human body
 unpredictable chain reaction  possible diseases
 it could breed new animal and plant diseases, new sources of cancer etc
 resistant qualities of GM bacteria in food can be transferred to other bacteria in the
environment
 loss of biodiversity: there will be lots of the plants humans
consider to be worthy and useful, the other plants will be
forgotten and will get lost between the cloned plants
 since the first GM food product was lab-tested, all animals
used in these tests have sooner or later died
Examples
 In 1989, dozens of
Americans died of a genetically
modified version of the food
supplement L-tryptophan
creating a debilitating ailment
(was released without safety
test)
 37 reported deaths and more
than 1500 disabilities
 the Japanese company who
produced this food supplement
destroyed every evidence to
prevent further investigation and
made a 2 billion dollar
settlement
 the loss of biodiversity in our food has led to
an increasing number of food allergies
 the human body is designed to eat food which
is alive and not copied
 cells in our body realize that gm-food is no
real food, which causes them to produce
antibodies and white cells  immune system
rejects the food and fights it  allergie!
Future Development
 Drugs in food
 Bananas producing human vaccines
 Fish maturing more quickly
 Trees yielding earlier
 Food without common intolerances
 increase of GM - products
 more safety testing
 benefits have to outweigh costs