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Self-Sustaining C3 Photosynthetic Plants Will End Hunger In Third World Countries
Kirsten Fuller
Associates
2013
609-970-7671
[email protected]
Steven Norris
Associates
2011
856-418-7247
[email protected]
Huba Nasir
HS Disploma
2010
856-383-4088
[email protected]
Jennifer Gizzi
Associates
2012
856-577-2580
[email protected]
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Kirsten Fuller, Steven Norris, Jennifer Gizzi, Huba Nasir
Self-Sustaining C3 Photosynthetic Plants Will End Hunger In Third World
Countries
Biographical Information:
A major problem in the world today is hunger. In this experiment, we hope to propose a
solution to this problem. Kirsten Fuller, Steven Norris, Jennifer Gizzi, and Huba Nasir are all
contributors to the research in this proposed lab experiment. Fuller has an Associates degree in
chemistry from Atlantic Cape Community College, was previously employed at a greenhouse,
and is currently a biology and education major at Rowan University. Norris has an Associates
degree in paramedicine, has knowledge in holistic medicine, and is currently working towards
B.S. in biology at Rowan University. Gizzi holds an Associates degree in science from
Burlington County College, interned with Burlington County parks and is currently working
towards a B.S. in environmental studies with a concentration in environmental science. Nasir is
working towards a B.S. in biology with a minor in chemistry. She has prior experience working
with plants in her high school horticulture club, and has helped growing crops on her family
farm. In addition to these qualifications, all members have previous experience working with the
photosynthetic light processes of Spinacea oleracea, which inspired its use in this experiment.
Background Information:
Photosynthesis is the process by which plants utilize sunlight, CO2, and H2O, to make
energy in the form of sugar and O2. One of the key molecules in photosynthesis is CO2, which is
gathered from the atmosphere along with O2. The atmosphere is always changing, and in recent
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times, the concentration of CO2 has been rising. This can affect photosynthesis because CO2 is a
limiting factor on plant growth in C3 plants (Li et al., 2007). When the CO2 concentration is low,
C3 pathway is less efficient due to higher rates of photorespiration (Busch et al., 2013). This
occurs because Rubisco, an enzyme, is non selective for CO2 or O2, and can utilize either one
(Busch et al., 2013). Because of this competition, photosynthesis is significantly reduced in C3
plants.
Since there are lower levels of CO2 in the environment, C3 photosynthetic plants are left
with an inefficient pathway for photosynthesis. This has led to an adaptation in which plants
modified their pathway for photosynthesis. Figure 1 illustrates this newly adapted version of
photosynthesis known as the C4 pathway.
Figure 1 shows the new C4 fixation pathway, compared to the C3 fixation pathway (Lara et al. 2011).
The C4 pathway has anatomical alterations, kranz anatomy, and biochemical alterations. An
example of a biochemical alteration is PEPC, which allows the plants to isolate the CO2 before it
binds with the Rubisco enzyme (Sage, 2004). These adaptations allow these plants to thrive in
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low CO2 environments. Due to the differences seen in the way CO2 is captured and utilized in
both C3 and C4 plants, it seems likely that raising the CO2 concentrations, higher than they are
now, will be a benefit to the biomass and fruit yield in C3 plants, while having minimal effects
on C4 plants (Valerio et al. 2011).
According to Phys.org, the level of CO2 in the atmosphere today is the highest it has been
in 15 million years. This staggering increase in emissions of carbon can be attributed to the
industrialization that is occurring globally. Over 91 percent of CO2 released into the atmosphere
today, comes from the burning of fossil fuels and cement. Instead of allowing this level of
emissions to continue to grow, utilizing the CO2 would be more useful. A higher level of CO2
creates the optimal conditions for a C3 photosynthetic plant, such as spinach, to grow; this can
create a more bountiful, and nutritional food source to help decrease the world hunger
problem.
If conditions for growing crops could be manipulated, the productivity could be
higher. According to a literature study performed by Reddy et al. (2010), there was a positive
response among different C3 plant species, when the CO2 levels were manipulated. Their study
not only showed an increase in plant height, but also doubled in basal diameter, number of
leaves, and biomass (Reddy et al. 2010). It was also found that these manipulated environments
with elevated CO2, showed no increase in biomass of C4 plant species.
We hope to utilize this information in order to test the effects of CO2 on spinach and
corn. Corn is the optimal test specimen for this experiment because it is a C4 photosynthetic
plant, it requires similar conditions to spinach, and it matures quickly. It is our assumption, that
a high level of CO2 will increase the biomass of spinach, a C3 plant, and not affect the biomass of
corn, a C4 plant. The data will also help us to prioritize land use based on crops that thrive at
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different CO2 levels. This will allow us to increase food production, and as a result, show a
decrease in the price, due to supply and demand.
Hypothesis:
Our first alternate hypothesis states that a high level of CO2 will yield an increase in
biomass of spinach, a C3 photosynthetic plant. The null hypothesis that corresponds to this
hypothesis states that high levels of CO2 will have no affect on the biomass of spinach.
Our second alternate hypothesis states that a high level of CO2 will decrease the biomass
of corn, a C4 photosynthetic plant. The null hypothesis that corresponds states a that high level
of CO2 will have no affect on the biomass of corn.
Proposed Research:
To test the two alternate hypotheses listed above, we plan to conduct an experiment
which compares the biomass of spinach and corn, that are exposed to higher levels of CO2, to
spinach and corn plants that are exposed to normal levels of CO2. In order to perform this
experiment, we will have three greenhouses equipped with CO2 pumps, supplied by
Environmental Growth Chambers Inc. We will also be using a gas analyzer, supplied from
PPSystems Inc. As seen in Figure
2, each greenhouse will have a
different level of CO2. We chose
400ppm, 600ppm and 800ppm of
CO2, based on research from
Valerio et al. (2011).
Figure 2: Diagrams of the three greenhouses that will be used to
conduct this experiment.
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Greenhouse 1 will act as the control of our experiment. This is because it is the closest to
the current atmospheric CO2 levels, as specified by CO2Now.org. Greenhouses will be kept at
constant CO2 concentrations 24 hours a day, for the duration of one year. In addition, plants in
each greenhouse will be kept at the same temperature, given the same amount of water, planted
in the same pot size, and have the same sunlight. Fertilizer for spinach will be administered in a
1-1-1 ratio, while the fertilizer for corn will be administered at a 1-2-1 ratio. Plants will be
started from seedlings at the beginning of the growing season. In each greenhouse, both corn
and spinach will go through two growing seasons. When each plant reaches maturity, we will
measure the biomass.
Expected Results:
We expect that greenhouse 3, containing 800ppm of CO2, will have the highest biomass
in spinach plants due to the efficient way the C3 pathway works in this type of environment. The
C4 pathways in corn plants are already efficient with their CO2 at lower atmospheric levels of
CO2 and therefore will not have a significant increase in biomass in greenhouse 3. Because of
this, we expect that in greenhouse 1, containing 400 ppm CO2, the C4 corn plants will
outcompete the biomass of the C3 spinach plants, despite ideal conditions of water, fertilizer, and
sunlight.
Increasing the CO2 concentration in the greenhouses, Valerio et al. (2011), found that
tomato plants had an increase in biomass, as well as a reduction in leaf area, and that the weed
had very little change in its biomass. We expect similar results to be found in our
experiment. Based on the data derived from Valerio et al. (2011), Figure 3 was constructed.
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Figure 3: Hypothetical graph of Spinach plants and Corn plants at 400ppm and 800ppm CO 2.
Our hypothetical data illustrates that at 400ppm CO2, 5g of spinach will be produced, while at
800ppm CO2, 10g of spinach will be produced. At 400ppm CO2, 5 g of corn will be produced,
and biomass will remain unchanged at 800ppm. We expect this to happen because C3
photosynthetic plants characteristically thrive at high levels of CO2. Therefore spinach will have
a higher quantity at the higher CO2 level. Consequently, C4 photosynthetic plants
characteristically thrive at lower levels of CO2. Therefore, corn will not change depending on
the CO2 level.
Justification of Research:
After reading the experiment done by Valerio et al. (2011), we felt that we could find
nutritional plants that would benefit from the increase in biomass from the increased CO2 in the
greenhouse air. This research would benefit the world because it would utilize excess CO2 in the
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atmosphere, in order to produce more food. According to WorldVision.org, more than 1 million
people in Kenya needed food aid in 2010. Although this is only one country that lies below the
global poverty line, it provides an excellent example of the necessity for a solution to the world
hunger problem.
By testing plants, such as spinach, in a higher CO2 environment, we can look at whether
it would be feasible to utilize areas near industrial plants as farmland, in order to decrease the
amount of CO2 that is returned to the atmosphere. We should be funded because our experiment
would not only improve the deteriorating atmosphere, but it would also increase the productivity
of crops using C3 photosynthesis, such as spinach, potatoes and tomatoes. This could increase
the amount of food that is available for distribution amount starving people, globally.
If our theoretical data were accurate, we would be able double the amount of food
production in C3 plants. One specific example of a C3 plant that supports the diet of many
people is rice. According to statistics stated in Hibberd, et al. (2008), in the next 40 years the
amount of rice produced within Asia will need to increase by 50% in order to prevent over 700
million people in the continent from entering malnutrition. In addition to maintaining the health
of all of those people, increasing production by 50% will also allow food prices to go down, due
to availability. Underdeveloped countries within Asia would in turn be able to buy more imports
of vegetables and fruits at a lower cost. This would leave more resources for other infrastructure
issues.
Third world countries also have many land areas that are currently being used up for their
industries; this contributes to the world’s pollution issue. Utilizing the CO2 emissions from these
industries in a positive manner could result in higher food production rates in C3 photosynthetic
plants. The increase in food production can be used to help feed the starving people in these
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countries, and help decrease their carbon footprints. Another side effect of decreasing costs is an
improved economy and a reduction in wasted food. If food becomes more affordable, other
countries will be able to purchase more of that food. This will decrease waste, and in turn
increase the prosperity of exporting to other countries.
Contribution Statement:
Each member of our group contributed equally to the brainstorming of ideas for this
proposal. Each member wrote his or her own biographical information statement for the first
section of the paper, and each member also selected a different section to work on. Steven
Norris wrote the expected results section and created the graph for the speculated biomass. In
addition Steven contributed largely to the background information section. Kirsten Fuller wrote
the proposed research section, contributed to the background information section, and created a
diagram of the greenhouses. Jennifer Gizzi researched the library database for relevant sources,
brainstormed the hypotheses, and contributed to the background information section. Huba
Nasir researched the library database for relevant primary and secondary sources, and wrote the
justification for the research section. Collectively, the members of the group worked to write
this contribution section, to write the acknowledgements, and to organize the entire proposal.
Acknowledgements:
We would like to thank Rowan University for providing us with the initial experiment on
Spinacea oleracea, which inspired our proposal. In addition, we would like to thank all of the
scientists whom were cited in this paper, especially Valerio et al. (2011). Without the work of
this research team, we would have no data supporting our research.
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Bibliography
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December 3, 2013].
Last time carbon dioxide levels were this high: 15 million years ago, scientists report. 2009.
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World Vision. 2013. Kenya facts. Available at http://www.worldvision.org/our-impact/country
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