hxh564
Testing the effect of salicylic acid on seed germination of
Vigna radita (mungbeans)
Biology internal assessment
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IB candidate code: hxh564
Session: May 2020
Date of submission: 7 March 2020
Research question:
What is the effect of salicylic acid on the germination and growth of “Vigna radita”(moong seeds)
and how faster it grows in 6 days?
Background information:
Salicylic acid was discovered by the Greek physician Hippocrates in the 5th century BC. [1] He found
that the bitter powder extracted from willow bark could relieve aches and pains and reduce fevers.
Aspirin is acetylsalicylic acid, which sounds a lot like salicylic acid, a beta hydroxy acid that’s great
for exfoliation, with anti-irritant and anti-bacterial properties that make it great for acne-prone skin.
The big difference is in the “acetyl”. This is what they look like:
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The little OH group on the phenyl ring (hexagon) on the salicylic acid has been replaced by a big
thing in the aspirin. This is called an acetyl group. That OH was the “hydroxy” bit of the beta hydroxy
acid – so aspirin isn’t a 1 (it’s a beta acetoxy acid).
Findings regarding the role of salicylic acid (SA) in seed germination are somewhat variable, depending on the plant genotypes and experimental conditions used, and thus the molecular mechanisms
underlying SA regulation of germination are still unclear 2. Here, we report that physiological concentrations of SA promote germination under high salinity by modulating antioxidant activity in Arabidopsis. Salicylic Acid is a beta hydroxy acid that occurs as a natural compound in plants. It has
direct activity as an anti-inflammatory agent and acts as a topical antibacterial agent due to its ability
to promote exfoliation. Salicylic acid is an odorless white to light tan solid. Sinks and mixes slowly
with water. Salicylic acid (SA) is a major natural product considered to be produced as a consequence
of resistance to the system after stimulating the plant with plant pathogens. Beyond its functions in
plants, SA and its acetylated derivate (commonly known as aspirin) are important pharmacological
agents for humans. Another name for aspirin is acetylsalicylic acid very similar to a hormone in plants
called salicylic acid. This hormone works to protect he plant from diseases and viruses that could
harm the plant. With the small amount of this hormone in the seed, it is not enough for the plant to
be 100% resistant diseases. When aspirin is added to water, it increases this resistance and allows the
plant to focus more of its energy on growing. This increases the speed at which the plant grows and
keeps the plant healthy. This is why aspirin is said to help plants in growth. The purpose of experiment
was to see if aspirin would affect the growth of the plant or not. The hypothesis of the experiment
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(The science of beauty)
2
(salicylic acid promotes seed germination-nph online library)
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was, if aspirin is added to plants, then plant with aspirin mixture will grow faster than the plant without aspirin mixture. Pulse crops, such as mungbean (Vigna radiata L.), play an important role in
protein production and economics of arid and semi-arid regions of the world. Mungbean is native to
India. In addition to its high nutritional value, due to its nitrogen fixation capability, cultivation of
mungbean can also improve soil fertility. Short growing season, production of high quality forage
and good heat tolerance are other important characteristics of this pulse crop.
I connect this topic to the unit on climate and ecosystem dynamics. It relates to this because I altering
the resources that one of the bean plants received and recorded how that affected he plant growth.
This shows how differences in growing condition changes the growth of a plant.
Hypothesis:
As the Aspirin concentration increases starting from 4-5tsp to 9-10tsp the growth rate of
Vigna radiata increases which in turn will increase the seed germination in a short period of time
because aspirin consists of an element named salicylic acid which helps the seed grow and germinate
faster hence it would take less time for the germination also.
Alternative Hypothesis: The seed will germinate faster if the concentration of aspirin solution is
increased.
Null Hypothesis : The seed will not germinate faster if the concentration of aspirin solution is
decreased.
Variables :
Independent variable: concentration of aspirin mixture (4-5tsp to 9-10tsp)
Dependent variable: growth of the seed (mungbean)
Controlled variable:
Variable
Effect on the data if not controlled
How the variables were controlled
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Volume of water If different volume of water were to be In both experiment the volume of
given to both
used this would lead to unreliable
water was kept same and then in
experiment
results.
second experiment the fine powder of
aspirin was added to 20 ml of water.
The amount of aspirin powder was
increased but the amount of water was
same.
Number of mung Same number of Mungbeans were
taken for both the experiment as it
beans
6 mungbeans were taken for each
experiment.
would be more easier to observe the
growth and it is sufficient to carry out
the experiment.
Time given to
each experiment
If the time differed then there would The experiment was observed for 6
be a major problem to get the
days.
observation as keeping same time
would give a clear idea of how faster
the seeds would germinate.
Type of seed
If different types of seed were used then
it would not have been easy to make out
the change as it each seed might take
different amount of time to germinate.
Water is considered a control variable because we have to make sure that each experiment got the
same amount of water — Acetylsalicylic acid is the active ingredient in aspirin and is derived from
salicylic acid, which is naturally found in willow bark, and many other trees. This natural cure all
really can boost the health of your plants.
Materials
• Aspirin tablets ( 20 tablets for 6 days was used)
• Mortar and pestle - 1
• Water - 20 ml per day was given to both experiment
• Cotton - a square piece inside both the petri dish
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• Petri dish - 2 for both experiment and of same size
• Mungbean - total 12 seeds, 6 for each
• spoon - 2 different spoon so there is no unfair result
• Graduated cylinder - 2 graduated cylinder were used one to measure the amount of water and the
other once to measure the amount of water+ aspirin solution.
• Stirring rod - 1 for the second experiment to stir the aspirin powder
• A ruler to measure the length of the radicle - 1
Procedure
• Measure the room temperature
• Find the mass of aspirin tablet
• Grind each tablet into a fine powder by using mortar and pestle
• Take 2 petri dish and place cotton inside the dish.
• Place 6 mungbean in each of the petri dish
• Name the petri dish, 1 with aspirin solution and 2 with water only
• Add the aspirin solution to the first petri dish and water to the second petri dish.
• Place them near window so the seeds get light
• Add 4-5 tsp of water to the 2 petri dish
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• Add 4-5 tsp of aspirin solution to the 1 petri dish but keep I kept increasing the solution after each
day.
• Make fine powder of 40 aspirin tablets for 6 days and add 1 litre of water to it and mix it well
• Measure the temperature of water and the aspirin solution
• Measure the growth of the seed everyday or observe the growth of the seed for six days.
Safety Measures:
CONCERN: ASPIRIN POWDER
HAZARD: Can cause redness if it fells on any part of our body. Also, development of Reye’s syndrome is a risk for children.It can also cause coughing and sneezing.
CONTROL: Wear a lab coat, gloves and safety goggles to prevent redness.
Setup of the experiment
Qualitative data:
The growth of the plant took time, like in the first experiment the seeds were given only water and
it was kept uncovered. According to the science the seeds should be covered for two days to get a
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better result of the sprouts but after seeing the results of experiment two with aspirin mixture the
rate at which the plants were growing was much faster than expected. It showed results more accurately when the concentration of the aspirin mixture was increased.The height of the seed gradually
increases with the amount of aspirin solution it gets per day.The experiment one was slow there
were not many changes and even by the end of the experiment after 6 days the seeds were not germinated fully a few of them were still the same as it was in the beginning.Both the experiments
were given their needed solution each day around 5pm in the evening. The statement which was
made regarding salicylic acid is correct as the changes have been seen. The reason of these results
for the aspirin solution is that I kept the amount of water same for both but i increased the concentration of the aspirin powder every day.
Day wise observation
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Observation in petri dish 1 ( with aspirin
solution)
No changes seen
2
No changes seen
3
A small part of radicle was seen
4
The radicle was growing
5
The length of the radicle was increasing
6
It radicle was fully out and grown
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In the first 2 days there was no change seen in the growth of the mungbean, but as I increased the
amount of the aspirin solution day by day there was a change seen. The radicle was seen on the fourth
day. The reason it was taking time was because there were other factors which were limiting the
growth like sunlight. Both the dishes were placed together near the window but did not get sufficient
amount of sunlight.
Quantitative data - Raw data:
Day wise observation
Observation in petri dish 2 (with water only)
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No changes seen
2
No changes seen
3
No changes seen
4
A small radicle coming out was seen
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It did not grow much in length
6
It did not grow much in length
Number of days
Day 1
concentration of aspirin
powder(grams)
1g
Height per day(cm)
1.0 cm
Day 2
2g
1.5 cm
Day 3
3g
4.1 cm
Day 4
4g
7.0 cm
Day 5
5g
10 cm
Day 6
6g
14 cm
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Increase in height of mungbeans in the aspirin
solution
y axis
x axis
Graph 1 shows the mean height of the mungbean and how it increases
over the six days.
Graph and Analysis:
The above graph shows the correlation between the height of the mungbeans in the time span of six
days.This graph depicts a linear positive correlation, suggesting that height of the mungbeans increases with the day. The more concentration of the aspirin solution the more faster the seed will
grow and germinate.It can be concluded from the graph that as the number of days pass by the
height of the seed in the aspirin solution increases where the height of the seed in normal water does
not show any big change in height. On the 4th day itself a big change in the height of the seed was
seen(day 4-7cm). The mean height of the seed is 8cm.
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Limitation and improvement:
The results obtained clearly supports the hypothesis, which states that an increase in concentration
the concentration of the aspirin powder shows that the seed germinates faster. This because the substance in the tablet aspirin which is salicylic acid. This substance helps the plant or seed to grow
and germinate faster. The limitation was that I could not cover the seeds with a cloth because that is
the usual process we use for germination at home but using this process also helped me gain
knowledge about salicylic acid and its factors. The strength was that I observed both experiment for
6 days and repeating the method gathered precise and fair results.
Source of error
Impact on results
Improvements
Measuring exact value of
aspirin powder in grams
Each day I was increasing the Using a weighing machine
amount of aspirin powder but if would help as it give the exact
it had a difference in the amount value of the amount.
the results would be unfair.
Measuring 20 ml of water.
This would again give unfair
results.
Using a measuring cylinder or
graduated cylinder would help to
get an accurate amount of water
to be used.
Kept the petri dishes outside the Keeping the petri dish outside It should have been kept inside
window
was a disadvantage as other the room near the window.
factors might have affected
the experiment
Measuring the length of each
seed separately
Observing only one or two seed Using a ruler and to check the
did not give a clear idea with
length everyday and noting it
which results are incomplete.
down.
The length of each seed should
have been measured for all 6
days.
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Conclusion:
Aspirin contains an active ingredient known as salicylic acid. It is derived from willow bark. This
acid enhances the immune system of plants (Plants prepare it naturally but in lower amounts) especially those in the nightshade family. Plants subjected to it get the boost in immunity power, which
helps them in combating with pests and microbial attack and prevents the formation of fungus leading
to increased growth rate of plants.Verticillium and fusarium wilt are common fungal diseases widely
distributed in soil and can wipe out an entire crop in a matter of days. Fortunately, according to a
recent study by the US Department of Agriculture, the use of aspirin spray can significantly reduce
the spread of fungus on the plant. It is also helpful in blight. A diluted solution of aspirin water for
plants provided accelerated germination and some resistance to disease and pests. Aspirin in vegetable gardens has been shown to increase plant size and yield.
Further extension
SA is commonly used to treat warts, acne, and psoriasis, while aspirin is one of the most widely used
medications in the world; its uses include treating pain, fever, swelling, and inflammation.
Salicylic is a main ingredient in many skin care products treating acne, psoriasis, calluses, corns,
keratosis pilaris and warts. Salicylic acid works as a keratolytic and comedolytic agent. It causes the
cells of the epidermis to shed more easily, opening clogged pores and neutralising bacteria within.
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Bibliography
1) Hayat, Shamsul & Khan, Nazir Ahmad & Alyemeni, Mohammed. (2013). Salicylic Acid: Plant
Growth and Development.
2) ”Salicylic Acid: Properties, Uses and History." UKEssays.com. 11 2018. All Answers Ltd. 03 2020
<https://www.ukessays.com/essays/biology/history-of-salicylic-acid-biology-essay.php?vref=1>.
3 "Salicylic Acid: Properties, Uses and History." All Answers Ltd. ukessays.com, November 2018.
Web. 6 March 2020. <https://www.ukessays.com/essays/biology/history-of-salicylic-acid-biologyessay.php?vref=1>.
4 Ghanbari, M., AR Eftekharian, S. Jahanmardi and M. Farzaneh, 2011. Effects of salicylic acid
pretreatment on the germination of radish (Raphanus sativus L.) under salt stress. J. New Knowledge
Sustain. Ag., 3: 45-50.
5 Saket Kumar., et al. “Growth and Yield Response of MungBean (Vigna radiata L.) in Different
Levels of Potassium". Acta Scientific Agriculture 2.6 (2018): 23-25
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IB DP Biology Internal Assessment Rubric Sheet
May 2020 Examination
Grading Sheet for Biology ( SL)
Candidate Code :
Personal Engagement
2
(8%)
engagement
1
Exploration
Analysis
Evaluation
Communication Total
6 (25%)
6 (25%)
6 (25%)
4 (17%)
24 (100%)
2
2
2
2
09
Internal Moderator Comments:
The report shows limited personal significance and curiosity. Research question is not focused and
hypothesis is not explained. Background information is relevant to the topic chosen. Variables are
identified and mentioned. Method is modified to answer the research question and safety measures
are outlined. Data collected and presented well in the graph. The report is easy to follow with some
omissions.
Personal Engagement
Exploration
Analysis
Evaluation
Communication
The justification given for choosing the research question and
the topic under investigation demonstrates limited personal significance, interest or curiosity.
RQ is not focused. Limited controlled variables are identified.
The report shows evidence of some awareness of the significant
safety and environmental issues that are relevant to the methodology of the investigation. The background information provided for the investigation is appropriate.
The report shows qualitative data and quantitative data. Appropriate and sufficient data processing is carried out that could
lead to a broadly valid conclusion.
The report shows evidence of no consideration of the impact of
measurement uncertainty on the analysis The processed data is
interpreted so that a limited conclusion to the research question can be deduced.
A conclusion is described which makes some relevant comparison to the accepted scientific context. Strengths and weaknesses of the investigation, such as limitations of the data and
sources of error, are described and provide evidence of some
awareness of the methodological issues involved in establishing
the conclusion. Further modification is suggested.
The report is well structured and clear: the necessary information on focus, process and outcomes is present and presented in a coherent way. The report is relevant and concise
thereby facilitating a ready understanding of the focus, process
and outcomes of the investigation.
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