Biotechnology and Agriculture

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Biotechnology and Agriculture

• By Wong Fu Shing 6A (14) Pang Keen Wha 6A (11)

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Wt is Biotechnology?

• Biotechnology means the use of scientific
  techniques to develop more productive crops and
  livestock has been used for more than a century.
  For example, crossbreeding different varieties of
  the same crop species has resulted in
  high-yielding hybrids such as the Green
  Revolution varieties of wheat and rice.
• In recent years, genetic engineering has
  systematically altered the genetic structure of
  plants and animals.
• Biotechnology can change the traditional plant
  and animal-breeding techniques in three ways
• 1. Desirable characteristics can be achieved
  quickly. Once genetic material is successfully
  introduced into the plant or animal, it will
  appear in successive generations.
• 2. Biotechnology concentrates on individual
  genes. As a result, only a single economically
  important characteristic is changed.
• 3. Genetic materials can be transferred among
  organisms that are unrelated.
• Biotechnology is not a modern development it has
  been around for a long time. Since the beginning
  of civilization, people have been using and
  modifying natural organisms to suit their needs.
  Early examples of the use of biological processes
  include beer brewing and bread baking.
• Modern biotechnological methods include the
  manipulation of genes, recombinant DNA
  technology, gene cloning, etc. These new
  biotechnologies are quicker, cheaper and more
  reliable when compared to those traditional
  biotechnologies.

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Biotechnology in the past

• For many years, farmers have sought to improve
  their crops by a process called cross
  pollination. The aim is to breed plants
  selectively to produce superior strains.
  Individual plants with desired traits are
  selected and artificially cross-pollinated, in
  the hope of producing offspring that share those
  traits. New strains have been developed, for
  example, to resist specific bacterial and viral
  attacks, to tolerate adverse environments such as
  drought or salty soil, and to increase yields.
• As our knowledge of classical genetics has
  increased, so has our ability to predict the
  outcome of particular cross breeding strategies.
  However, despite this knowledge, cross breeding
  still remains a somewhat hit or miss affair and
  it is expensive in both time and money.

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The problem faced in agriculture
Ever since humans first farmed for survival,
crops have been ruined by bacterial and viral
infection, attacked by insects, eaten by worms,
choked and weakened by weeds and damaged by
unpredictable weather. We have countered many of
these problems by selecting and breeding plants
resistant to these environmental hazards.
However, conventional plant breeding techniques
are slow, so we have also used an array of
chemicals to help agricultural plants in their
battle for survival. Unfortunately, chemicals,
such as DDT, 2,4,5-T, 2,4-D, dieldrin and some
organophosphates, have caused biological and
ecological problems. Insects have become
resistant to some chemical pesticides, for
example. Other compounds, once thought to be
safe, have now been shown to persist in the
environment and enter the food chain. The
developing techniques of biotechnology, applied
to modern agriculture, offer an additional tool
in our constant battle to provide more food at a
reasonable price for the world's growing
population.
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Genetic Engineering
Scientists now understand the coding system
underlying the chemical instructions, or genes,
that are passed on from one generation to the
next. It is based on a substance called
Deoxyribonucleic Acid (DNA). A gene is actually a
segment of DNA with a message encoded in its
chemical structure. Once scientists understood
the DNA code, they began looking for ways to
change the instructions carried by genes - to
introduce new instructions that would cause a
cell to produce needed chemicals, or carry out
useful processes, or give an organism desirable
characteristics. The result was modern genetic
engineering - the science of manipulating and
transferring chemical instructions from one cell
to another.
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Advantages of modern biotechnology
Modern biotechnology makes plant-breeding
programs more effective in two important ways.
Firstly it allows breeders to choose specific
genes, incorporating into the new plant only
those traits they want. This makes the process of
trait transfer faster, more exact, cheaper and
less likely to fail than traditional
crossbreeding methods. Secondly, it gives
breeders the freedom to incorporate genes from
unrelated species into the plant they are trying
to improve. In classical crossbreeding, only
plants that are similar may be crossbred.
However, the genetic engineering techniques of
modern biotechnology allow genes to be swapped
between unrelated species, so that plant-breeders
can incorporate new features that would normally
not be available.
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What can biotechnology do for agriculture?
Millions of dollars are spent every year looking
for new or more potent chemicals to combat insect
damage, disease and nutrient deficiency in crops.
Imagine the advantages of having plants that
could protect themselves from insect attack, or
from bacterial and viral infection, or of feed
plants that could supply more of the nutrients
needed by the animals who graze on them. Modern
biotechnology is already helping to make these
things possible.
There are 5 examples, Natural insecticides,
Disease protection, Improved feed crops
,Selective herbicide resistance, Micropropagation
(tissue culture)
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1. Natural insecticides
An insecticidal protein has been successfully
incorporated into tomato plants to provide
protection from some leaf-eating insects. The
protein comes originally from Bacillus
thuringiensis, a naturally occurring bacterium
that lives in the ground. Using genetic
engineering techniques, scientists have inserted
the gene for this protein into the plant's
genetic material. When an insect eats the
modified plant, the protein is released and the
insect dies.
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2. Disease protection

• Tobacco mosaic virus (TMV) causes the leaves of
  some important crop plants including the tomato
  to wither and die. Scientists have incorporated
  into the tomato plant a gene that protects it
  from infection. It has the same effect as a
  vaccine for humans. This approach is now being
  applied to other viral diseases in crops.

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3. Improved feed crops

• CSIRO has been working to develop a sulphur-rich
  feed plant for sheep. Research has shown that
  sulphur supplements in the diet help sheep
  produce better quality wool fibre. Scientists
  believe it would be more cost effective to feed
  the sheep on pasture that was naturally
  sulphur-rich. Using biotechnology, CSIRO
  scientists have developed lucerne strains that
  produce a sulphur-rich protein in their leaves.
  They now plan to develop pasture grasses with the
  same characteristics.

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4. Selective herbicide resistance

• Glyphosate is an environmentally-friendly,
  widely-used broad spectrum herbicide. It is
  easily degraded in the agricultural environment
  and works by interfering with an enzyme system
  that is present only in plants. Unfortunately,
  the herbicide kills crop plants as well as weeds,
  but scientists have now used genetic engineering
  methods to breed crop plants that are glyphosate
  resistant. By planting these modified crops,
  farmers can control weeds by spraying with
  glyphosate alone.

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5. Micropropagation (tissue culture)

• Plant breeders already use micropropagation
  techniques - in which whole plants are grown from
  single cells or from small plant parts for rapid
  multiplication of identical, disease-free plants.
  If necessary genetic engineering can be used to
  incorporate desired characteristics from other
  species into the cell prior to propagation.

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The future

• Current research will see the improvement and
  development of crops for specific purposes.
  Plants that require less water could be developed
  for countries with arid climates. Crop plants
  engineered to be tolerant to salt could be farmed
  in salt-damaged farmland or could be irrigated
  with salty water. Crops with higher yields and
  higher protein values are also possible.
  Biotechnology can help
• (1) Improve farming productivity
• (2) Protect our environment by allowing reduced
  and more effective use of chemical pesticides and
  herbicides
• (3) Reduce food costs
• Biotechnology can provide us with a healthier and
  safer environment, and make agriculture more
  productive.

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Biotechnology in agriculture

• While respecting ethical concerns, governments
  should recognize biotechnology's potential for
  increasing food supplies and alleviating hunger
• Biotechnology could help solve many problems
  limiting crops and livestock production in
  developing countries. For example,
  biotechnology-derived solutions for biotic and
  abiotic stresses, built into the genotype of
  plants, could reduce use of agrochemicals and
  water, thus promoting sustainable yields.

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Some Example of the use of biotechnology in
agriculture (1)

• Scientists at the ARS/University of California
  Plant Gene Expression Center are the first in the
  world to report success in genetically
  engineering barley. The bioengineered barley may
  help plants resist a damaging virus.

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Some Example of the use of biotechnology in
agriculture (2)

• Enzymes produced from using recombinant DNA
  methods are used to make cheese, keep bread
  fresh, produce fruit juices, wines, and treat
  fabric for blue jeans and other denim clothing.
  About 80 percent of cheese is made using a
  genetically engineered enzyme called chymosin
  produced by microbes. This enzyme is chemically
  identical to the enzyme rennet, which is isolated
  from the contents of the forestomach of an
  unweaned calf. It is easier to purify, more
  active and less expensive to produce because
  microbes are more prolific, more productive and
  cheaper to keep than calves.

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Some Example of the use of biotechnology in
agriculture (3)

• Many of the products we eat, wear and use are
  made using the tools of biotechnology. Using
  genetic engineering scientists are able to
  enhance agronomic characteristics such as biotic
  and abiotic stress resistance, yield and growing
  season, vitamins, minerals, texture, color,
  flavor, shelf life and other desirable properties
  of production crops. Plants can be used to
  produce completely novel products such as
  vaccines, therapeutic proteins and plastics.
  Transgenic techniques are applied to farm animals
  to improve growth, fitness and other qualities of
  beef and dairy cattle, poultry and fish.

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Marketing

• Biotechnology is increasingly market and demand
  driven, and most of its products result from
  research and development investments by the
  private sector in developed countries. There is
  little point in developing a new technology if
  there is no market for the product. The same is
  valid for new varieties of plants and new breeds
  of animals, new vaccines and diagnostic kits.
  Market studies are fundamental in defining which
  ventures should be undertaken. Given that
  commercial considerations may not necessarily
  reflect social concerns and needs, there remains
  a pivotal role for public-sector research.

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The end

• Biotechnology in agriculture can really do humans
  good provided that we make good use of it!!