Summary: Genetic engineering is a controversial subject according ...

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11 Δεκ 2012 (πριν από 4 χρόνια και 6 μήνες)

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Summary:
Genetic engineering is a controversial subject according to previous reports in newspapers and
television. Some articles raise serious concerns about this emerging technology whilst others praise
it's future possibilities. Especially the issue about cultivation of genetically modified crops has been
subject to a vast number of discussions in politic and science. This article offers an conclusion
about the aspects and properties of genetic engineering in agriculture and crop breeding. It discusses
the difference between well-tried, old fashioned breeding and the emerging possibilities of genetic
engineering. The report mentioners criticisms towards the technology, gives examples of
contemporary applications in agriculture and offers an introductions of possible applications in
future.

Main:
The conventional way of plant breeding was able to create a wide range of commercial plants and
crops with a variety of valuable agronomic traits. Mexican grass has been converted into maize just
as a usual grass plant from the Middle East has been turned into wheat. Although this process of
breeding has been very successful in transforming usual plants into crop plants by increasing the
yield and improving certain abilities of those plants, the process itself took many thousand years to
result into the type of maize or wheat as we know it today. The processes of common breeding is to
a large extent a hit and miss procedure by which the best looking plants have been sorted out for
further breeding over centuries.

An alternative to this classic way of breeding is a rapidly evolving part of biotechnology. On of the
main disadvantages of common breeding is the limiting
factor set by the diversity of species. Genetic
engineering allows the scientist to overcome those
boundaries through the use of recombinant DNA
techniques.



The United States are one of
the leading countries
regarding the use of genetic
modified plants in
agriculture. The proportion
of genetically modified soy constituted 91% of the total soy area farmed in the USA in 2007. Still
the issue of genetic modified organisms also called GMOs remains controversial. A crucial part of
the European population tends to deny the introduction of GMOs into agriculture in general, but
especially into the food production. The reason for this protest emerges from the criticism towards
the manipulation of living organisms taking into account the complexity of genetic and biochemical
mechanisms and the possible side effect that may result. Some claims predict the cultivation of GM
crops will cause an irreversible impact on the biodiversity of the environment due to cross breeding
with naturally occurring species. Whilst others point out that some scientific studies raised serious
health issues scrutinizing the safety of food based on GM crops.
Though due to the today's rapid development of biotechnologies genetic engineering is also
considered as one of the most promising fields of current research. It may provide the potential to
play an essential role in solving some of the serious problems of mankind's future. Especially in
perception of the exponential growth of our world population, future threats as global warming and
the limited availability of fossil fuels it seems as new technologies would be more important than
any time before.

How can genetic engineering be beneficial for humans?
The genetic information of almost every living cell is encoded in a molecule known as DNA. This
molecule is made up of a vast number of different genes which control basically all the functions of
an living organism. The process of genetic engineering is capable to transfer a genetic information
of one organism to a another organism and hence is able to cause a significant change in an
organism.




Genetic engineering is a such promising technology because it enables researchers to modify and
reorganise the properties of plant or bacteria by introducing or erasing a strand of DNA.
A famous example how to this technology is applied is a GM crop called Bt-corn.
Bt-corn is a genetically modified version of common corn which is capable to produce a protein
which is usually not expressed by plants, but makes the corn resistant to a specific type of pest
insects. The genetic information to express this protein originates from a soil bacteria called
Bacillus thuringiensis. The inserted gene enables the expression of a protein that kills caterpillars
wich constitutes a threat for agricultural mono cultures. The Bt-corn is economical and ecological
valuable as the farmer has to make us of less pesticides to grow the crop.

Another example of commercialized GM crops posses the widespread trait of improved herbicide
and pesticide tolerance. As well as pests are plants occasionally sensitive to high concentrations of
toxins. The increased tolerance enables the farmer to apply an extended variety of herbicides and
pesticides to protect his plants from pests. Although this trait is common among today's GM crops,
it remains one of the rather controversial examples as farmers growing the GMO are encouraged to
make use of more pesticides.

Despite the traits and crops of genetically engineered plants wich are already available, the far more
interesting question is which new traits could be beneficial for our future. The following proposals
consider the use of genetic engineering to provide sustainable solutions for the popular issues
regarding the food and energy.
An often discussed idea is the development of GM plants with a increased tolerance to the slat
content in soil. This new trait would be especially beneficial for areas where salinization is a major
problem due to a very hot climate. Dry and “salty” soil results in significantly smaller crop yields
wich affects predominantly developing counties. The life expectancy and life quality in such poor
countries could possibly be improved by a new type of crops which have the ability to adapt to such
infertile environmental conditions.


A promising approaches of biotechnology is the directed increase of oil content. Plant oil is high in
energy content and thus constitutes a perfect substrate for the production of biofuels. Some
experiment showed that due to the use of genetic engineering techniques the plants contained a
significantly higher proportion of oil. This proposal might be an important step towards a future
independent from fossil fuels.



References:

Introduction:
www.eolss.net/ebooks/.../C17/E6-58-03-04.pdf


Critics:
http://library.thinkquest.org/C004367/be10.shtml


GM Soy:
http://www.gmo-
compass.org/eng/agri_biotechnology/gmo_planting/283.usa_cultivations_2007.html


Bt-Corn:
http://www.ca.uky.edu/entomology/entfacts/ef130.asp


Traits of GM crops:
http://www.epa.gov/oppbppd1/biopesticides/reg_of_biotech/eparegofbiotech.htm


Tolerance to salt content in soil:
http://www.plantstress.com/Files%5Cengineering_salt.htm


Biofuel:
http://www.nature.com/nrg/journal/v9/n6/execsumm/nrg2336.html


Pictures:
http://www.ces.ncsu.edu/resources/crops/ag546-1/