Powerpoint template for scientific posters Swarthmore College

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Testing possible photosynthetic variances in
transgenic plants A four year study Paul A.
Ruddle IILowndes High School, Valdosta, Georgia
Conclusions The practical considerations of this
research include utilization of this model in
continued research for improving transgenic
plants. Before researching this subject, the
author never thought about the implication of
genetic engineering on seemingly unrelated basal
processes such as photosynthesis. As a result of
the experimentation, the author has reached three
conclusions. The first conclusion that the
author reached is that, in the earlier stages of
growth, the Round-Up Ready soybeans were more
efficient in reducing NADP and had a greater
amount of essential photosynthetic molecules
present, thus, resulting in greater overall
photosynthetic capabilities. However, the
efficiency of Photosystem II was similar for both
types of soybeans in the earlier stages of
growth. In the later growth stages, the
standard, non-transgenic soybeans had a similar
amount of essential pigments as the Round-Up
Ready soybeans. But, the standard plants were
more efficient in reducing NADP. The second
conclusion that the author reached is that, in
the earlier stages of growth and in the later
growth stages, the Round-Up Ready cotton was as
efficient in reducing NADP, as the standard,
non-transgenic plants. Also, in the early growth
stages the Photosystem II efficiencies were
similar. The third conclusion that the author
reached is that, in the earlier stages of growth
and in the later growth stages, the Round-Up
Ready corn was as efficient in reducing NADP, as
the standard, non-transgenic plants.
Introduction Recently, agriculturalists have been
directly altering the genetic structure of plants
in an effort to improve crop production. This
restructuring is conducted by introducing a new
gene into the plant. According to the National
Agriculture Statistics Service (electronic
communication, December 5, 2003), many crops
being grown are genetically altered. Eighty-one
percent of the United States (US) 2003 soybean
crop used an alternate version of the EPSP
synthase, thus making the soybeans resistant to
the popular herbicide glyphosate, also known by
the trade name Round-Up. Also, two-fifths of
the US corn crop utilized variants of the Cry
gene to produce crystal delta-endotoxins that
kill caterpillars and other lepidopteran
insects. These and other desirable traits have
been introduced by genetic engineering. However,
the full ramifications of genetic alterations
such as these are not yet known. The Food and
Drug Administration (FDA) claims to test to make
sure only desirable traits are introduced into
the crop, but they have limited time and money to
devote to testing (Thompson, 2000). The vast
majority of testing is performed by the
individual companies seeking FDA consultations
(List . . ., 2005). Many people are concerned
with the effects of genetically altering plants
(Passacantando, 2000). The problem is that the
potential adverse side affects of engineering the
DNA of plants is not yet known. Just like in
earlier societies, most food for contemporary
society comes from plants.
Results
Objective The objective of this research is to
determine if the rate of photosynthesis varies
significantly between Round-Up Ready and
standard, non-transgenic, plants. If a plants
photosynthesis processes do not function
correctly, growth could be severely inhibited.
The production of lower quality plants could
result, and in turn, reduced crop yields could
emerge.
Relevant Applications to Biotechnology This
project proves that the genetically altered
plants have fewer unwanted side effects than some
critics have asserted. After disseminating this
information, the agriculture industry can focus
on other challenges. This new information could
also be an indicator to agricultural companies or
other related organizations to conduct similar
tests. The findings of this research could be
beneficial, especially for generating related
studies. Different companies public relations
departments could publicly release this data to
consumers. A media campaign comprised of this
data and other helpful information could help
lessen the fear of genetically altered crops.
Consumers need to understand that the use of
genetically engineered plants is just a natural
progression of agricultural methods.
Materials and Methods Three testing methods were
used to evaluate three varieties of Round-Up
Ready plants versus their standard,
non-transgenic, counterparts over a four year
testing period. The varieties tested were
DP6880RR/DP6926 soybeans, DK687RR/DK687 corn and
DP5415RR/DP5415 cotton. The plants were grown in
the researchers high school greenhouses. A
chlorophyll fluorometer in a FV/FM testing mode
was used to measure the photochemical efficiency
of Photosystem II. Paper chromatography was used
to measure the amounts of the essential
photosynthetic pigments chlorophyll a,
chlorophyll b, the xanthophylls, and the
carotenoids. A spectrophotometer was used to
measure DPIP reduction, indicating the rate at
which NADP is being reduced to NADPH, thus
measuring the photochemical efficiency of
Photosystem I.
Acknowledgments The author would like to thank
the following businesses, organizations, and
individuals for the help they rendered in the
completion of this project Ace-Electric James
Corbett John Howeth Jason Peake John
Ruter Ford Motor Company Griffin LLC Andy
Harrison Lowndes High FFA Chapter Lowndes High
Science Club Monsanto Corporation John
Newton Carmen Ruddle Claudea Paul Nancy
Hand Stacy Byrd General Contractors of
Valdosta USDA Research Station at Tifton,
Georgia
Interpreting the Data FO- Non-Variable
Fluorescence FM- Maximal Fluorescence FV/FM-
Variable Fluorescence/Maximal Fluorescence,
Quantum Yield The researcher conducted an
analysis of variance (ANOVA) test to evaluate for
a difference in photosynthesis rates between the
Round-Up Ready and standard, non-transgenic
cotton. A single factor comparison was used that
compared the rates of photosynthesis between the
two groups. Since the P-Value for all three sets
of data FO, FM and FV/FM was above .05, no
significant difference in photosynthesis rates
existed. NOTE The remainder of the research
data for the cotton as well as the soybeans and
corn and interpretations are available in the
research paper on the table.