lemna sp arm
TRANSCRIPT
OBJECTIVE
To investigate the effect of plant mineral deficiency.
To investigate the types of minerals that is important for the growth of the plant which is the
micronutrient and macronutrient.
To develop careful observing skills on the development changes occurred on Lemna leaves.
To develop certain experimental skills, namely working safely, producing valid results and
drawing valid conclusions from the results
PROBLEM STATEMENT
What is the effect of plant mineral deficiencies on Lemna plant or leaves?
EXPERIMENTAL HYPHOTHESIS
The experiment is conducted to investigate the grow of plant (Lemna sp) in petri dish with
different lack of deficiency mineral. Plant in the complete culture solution which has all the
nutrients required to produce the greater number of leaves and number of them also will
increase. While the poor growths of the plants are the highest in the lacking of macronutrient
minerals such as nitrogen, calcium and magnesium while little in other lacking of
micronutrient minerals.
NULL HYPHOTHESIS
There will be no difference in the physical qualities of Lemna sp immersed in normal
solution or other solution deficient in any mineral as the deficiency of plant mineral will not
affect the growth and development of the plants.
VARIABLES
Manipulated variables: Different type of mineral deficiency solution
Responding variables: The growth of Lemna sp.
Constant variables: Volume of culture solution (20 ml), type of Lemna sp., initial number of
leaflets for each culture solutions (5 leaflets).
INTRODUCTION
Plant required 16 elements which are vitals for growing and survival of the plant. It is divided
into two parts: non mineral and mineral. on-mineral part need by plant consists of the
hydrogen(H), Oxygen(o) and Carbon( C).All these non- minerals can be obtained from the
process of synthesis of carbohydrates by photosynthesis.Eventhough,plant can make its own
food by photosynthesis, plant still need other minerals which is essential for the healthy
growth.
In the other hand, Plants needs total 13 mineral nutrients for the growth. The elements
that are required or necessary for plants to complete their life cycle are called essential plant
nutrients. Each of these nutrients has a critical function in plants and is required in varying
amounts in plant tissue. When plants suffer from malnutrition, they show symptoms of being
unhealthy. Too little or too much of any one nutrient can cause problems. So the right amount
of the minerals is necessary.
Plant nutrients can be divided into two categories; macronutrient and micronutrient.
Macronutrients are major nutrients that are consumed at larger volumes compared to
micronutrients. Calcium, magnesium, phosphorus and nitrogen are examples of
macronutrient. Micronutrient or trace nutrient, are less required but they do help in the
development of plants. Iron, sodium and nickel in this category. Plants take up mineral in the
form of mineral ions through the process of root pressure in transpiration by active transport
Nitrogen's Role
Of the three major nutrients, plants require nitrogen in the largest amounts. Nitrogen
promotes rapid growth, increases leaf size and quality, hastens crop maturity, and promotes
fruit and seed development. Because nitrogen is a constituent of amino acids, which are
required to synthesize proteins and other related compounds, it plays a role in almost all plant
metabolic processes. Nitrogen is an integral part of chlorophyll manufacture through
photosynthesis. Photosynthesis is the process through which plants utilize light energy to
convert atmospheric carbon dioxide into carbohydrates. Carbohydrates (sugars) provide
energy required for growth and development. Of all the elements required for crop
production, nitrogen poses the greatest environmental threat through contamination of surface
and ground water. Nitrogen fertilizer is available in both organic (manures) and inorganic
forms. The amount of nitrogen in organic sources varies with source material and its state of
decomposition. However, for commercial crop production, the following inorganic fertilizers
are primarily used: ammonium nitrate (33.5%N), potassium nitrate (13% N), sodium nitrate
(16% N), calcium nitrate (15.5% N), urea (46% N), mono-ammonium phosphate (18% N),
di-ammonium phosphate (46% N) and liquid nitrogen (30% N). Legume crops require little
or no nitrogen fertilizer. Beneficial bacteria that live in the roots of these plants capture
nitrogen from the atmosphere. This nitrogen is available for use by the plant. Nitrogen is also
used by microbes to break down organic matter.
Phosphorus' Role
Normal plant growth cannot be achieved without phosphorus. It is a constituent of
nucleic acids, phospholipids, the coenzymes DNA and NADP, and most importantly ATP. It
activates coenzymes for amino acid production used in protein synthesis; it decomposes
carbohydrates produced in photosynthesis; and it is involved in many other metabolic
processes required for normal growth, such as photosynthesis, glycolysis, respiration, and
fatty acid synthesis. It enhances seed germination and early growth, stimulates blooming,
enhances bud set, aids in seed formation, hastens maturity, and provides winter hardiness to
crops planted in late fall and early spring. The meristem region of growing plants is high in
phosphorus. The highest levels of phosphorus are found in soils where tobacco and vegetable
crops have been grown. High concentrations are also found in fields where heavy rates of
poultry litter have been applied.
Potassium's Role
Potassium has many functions in plant growth. It is essential for photosynthesis,
activates enzymes to metabolize carbohydrates for the manufacture of amino acids and
proteins, facilitates cell division and growth by helping to move starches and sugars between
plant parts, adds stalk and stem stiffness, increases disease resistance, increases drought
tolerance, regulates opening and closing of stomata, gives plumpness to grain and seed,
improves firmness, texture, size and colour of fruit crops, and increases the oil content of oil
crops. Although not an integral part of cell structure, potassium regulates many metabolic
processes required for growth, fruit and seed development. Many vegetable and fruit crops
are high in potassium, which is vital for animal and human nutrition. Indeed, the health and
survival of man and beast is dependent on potassium. The lowest amount of potassium is
found in sandy coastal plain soils where it is subject to leaching. The higher concentrations
are found in the clayey soils of the piedmont and mountain regions. High potassium is also
found in areas where animal and poultry wastes have been applied.
Calcium's Role
Calcium ions play a role in the permeability of membranes as they can combine pectin in
the middle lamella of plant to form calcium pectate in which holds cells together. It provides
elasticity and expansion of cell walls, which keeps growing points from becoming rigid and
brittle. Calcium also acts as a base for neutralizing organic acids generated during the
growing process and aids in carbohydrate translocation and nitrogen absorption. Indeed,
calcium deficiency symptoms appear in the meristem regions of leaves, stems and roots.
Younger leaves are affected first and are usually deformed. Roots on calcium-deficient plants
are short and stubby. In cases, the leaves hook downwards and exhibit marginal necrosis.
Magnesium's Role
Magnesium is a constituent of the chlorophyll molecule, which is the driving force of
photosynthesis. It is also essential for the metabolism of carbohydrates (sugars). It is an
enzyme activator in the synthesis of nucleic acids (DNA and RNA). It regulates uptake of the
other essential elements, serves as a carrier of phosphate compounds throughout the plant,
facilitates the translocation of carbohydrates (sugars and starches), and enhances the
production of oils and fats. Magnesium deficiency is most prevalent on sandy coastal plain
soils where the native magnesium content is low.
Sulphur’s Role
Sulphur is an essential component in the synthesis of amino acids required to
manufacture proteins. Sulphur is also required for production of chlorophyll and utilization of
phosphorus and other essential nutrients. Sulphur ranks equal to nitrogen for optimizing crop
yield and quality. It increases the size and weight of grain crops and enhances the efficiency
of nitrogen for protein manufacture. Crops that have a high nitrogen requirement must have
adequate sulphur to optimize nitrogen utilization. Sulphur increases yield and protein quality
of forage and grain crops along with production and quality of fibre crops.
Iron’s Role
Iron is essential for the formation of chlorophyll. Plants absorb iron as an ion through
their foliage as well as their roots. Uptake is strongly affected by pH. Chelated iron is readily
available for use by the plant; other forms of iron may be tied up in the soil.
USESDEFICIENCY
P nucleic acid, phospholipid, reproduction, ATPstunted, dark leaves, necrotic spots, anthocyanin
in stem and leaves, thin weak stem
K ion balance, respiration enzymes
marginal chlorosis, necrosis at tips and edges,
curled/crinkled leaves, old leaves first, short
weak stems, susceptible to diseases
N amino acids, nucleic acids
stunted, chlorosis of older leaves, abscission,
thin stems with lignin or anthocyanin as "sink"
for photosynthate
S cysteine, methionine, CoA, etc. chlorosis of young leaves first
Ca enzyme cofactor, cyclosis, pectinshooked leaves, necrosis of young meristems,
severe stunting as meristems die
Fe cytochromes in respiration, enzymes chlorosis between veins on young leaves first
Mg chlorophyll element, enzyme cofactorchlorosis between veins on older leaves first,
early abscission
Table 1.1 shows Summary from nutrient needed for plant taken from
http://plantphys.info/plant_physiology/minerals.shtml
Lemna sp
Lemma is small, free-floating aquatic water plants found in ponds. It is from the Duckweed
family. Lemma plants reproduce asexually by vegetative propagation, where two daughter
plants bud off from the adult plant. When they are big enough, they will separate from the
mother leaf and can reproduce it. Sometimes, Lemma plants can have up to 3 or 4 buds. This
form of growth is a very rapid colonisation of new water. Duckweeds are flowering plants,
nearly all of them known to reproduce sexually, flowering, and producing seed under
appropriate conditions. Like normal plants, they grow through a process called
photosynthesis where they can use sunlight, minerals, carbon dioxide and water synthesise
the food they need. Lemna has been used for testing toxicity of certain chemicals. Lemna can
be transformed by molecular biologist to express proteins of pharmaceutical interest. Lemna
are genetically engineered to produce in the growth medium at high yield, and thus reduce the
manufacturing costs. It is easily grown in garden ponds, where it removes excess nutrients
from water and providing sheds to inhibit algae growth. Their high fat and protein content
makes them a source of food for animals and poultry.
Diagram 1.1 shows from Duckweed photo - www.cmuscmr.cmu.edu.
USES
Lemna has been used for testing toxicity of certain chemicals. Lemna can be transformed by
molecular biologist to express proteins of pharmaceutical interest. Lemna are genetically
engineered to produce in the growth medium at high yield, and thus reduce the manufacturing
costs. It is easily grown in garden ponds, where it removes excess nutrients from water and
providing sheds to inhibit algae growth. Their high fat and protein content makes them a
source of food for animals and poultry.
APPARATUS
Forceps, sticker and marker pens for labelling, Petri dishes, measuring cylinder, Petri dish
covers.
MATERIALS
A range of nutrient solutions, including solutions with: all nutrients present, lacking nitrogen,
N, lacking phosphate, P, lacking potassium, K, lacking magnesium, Mg, lacking calcium, Ca,
lacking iron, Fe, lacking sulphur, S, lacking all nutrients (distilled water), Lemna sp
METHODOLOGY
1. Nine Petri dishes were rinsed with water and wiped dry.
2. They are labelled in match with the type of culture solutions used, respectively.
3. All the Petri dishes were filled with 20 ml of culture solution respectively.
4. As much as five single Lemna (if single was used) was chosen and scattered into each Petri
dish that already filled with the solution.
5. The Petri dishes were covered on with lid.
6. All the Petri dishes were arranged in a tray and put under a shed along the corridor.
7. All the specimens were left for 10 days and observation was made for every two subsequent
days in interval.
8. The colour and size was observed specifically whereas the number of leaves and number of
plant were calculated and data obtained was tabulated for comparison.
RESULT
Nutrient Solution Total Number of Leaflets
Day 1 Day 2 Day 4 Day 6 Day 8 Day 10
All minerals present 5 6 8 9 9 8
No minerals present 5 8 9 9 9 7
Lacking
Iron
5 7 8 8 8 7
Lacking Potassium 5 7 6 7 8 8
Lacking
Magnesium
5 6 7 8 9 9
Lacking
Nitrates
5 7 8 7 8 8
Lacking Phosphates 5 7 7 8 8 8
Lacking
Calcium
5 5 4 4 4 4
Lacking Sulphates 5 9 9 9 9 9
Table 1.2: observations on the number of leaves of Lemna
Solution Day 1 Day 2 Day 4 Day 6 Day 8 Day 10
All
nutrients
present
Green Green Green with
white spots
Green with
white spots
Green with
white spots
Green
with
white
spots
Lacking
calcium
Green Slightly
bleached
Completely
bleached
Completely
bleached
Completely
bleached
Dead
Lacking
iron
Green Green
with
yellow
spots
Green with
yellow
spots
Green with
yellow
spots
Green with
yellow
spots
Less
green
Lacking
potassium
Green Green 1 yellow, 3
green
Mostly
green with
white spots
Mostly
green with
white spots
Some
white,
some
green
Lacking
magnesium
Green Green Green with
white spots
Green with
white spots
Green with
more white
spots
Some
are
bleached
Lacking
nitrogen
Green Green Some
slightly
yellow
Some
slightly
yellow
Green with
white spots
Green
with
white
spots
Lacking
phosphorus
Green Green Green Green Green with
little white
spots
Green
with
little
white
spots
Lacking
sulfur
Green Green Green with
few white
spots
Green with
white spots
Pale green Pale
green
Lacking all
nutrients
Green Slightly
bleached
Slightly
bleached
All
bleached
All
bleached
All
bleached
Table 1.3: observations on the colour of Lemna leaves
Table 1.5: observations on the general growth of Lemna plants
Solution Day 1 Day 2 Day 4 Day 6 Day 8 Day 10
All Normal Large Larger Larger Larger Larger
Lacking nutrient in culture solution
Growth of Lemma plant
Day 1 Day 2 Day 4 Day 6 Day 8 Day 10have all
nutrient
Increase increase increase increase increase increase
calcium Increase increase decrease decrease Dead Dead
iron Increase increase increase increase Increase increase
potassium Increase increase increase increase Increase increase
magnesium Increase increase increase increase Increase increase
nitrogen Increase increase increase increase Decrease decrease
phosphorus Increase increase increase increase Increase increase
sulphur Increase increase increase increase Increase increase
no nutrient Increase increase increase increase Decrease decrease
nutrients presentLacking calcium
Normal Larger Larger Smaller / shrink
Smaller / shrink
Dead
Lacking iron
Normal Slightly larger
Slightly larger
Larger Larger Larger
Lacking potassium
Normal Larger Larger Larger Larger Larger
Lacking magnesium
Normal Larger Smaller /shrink
Smaller /shrink
Smaller /shrink
Smaller /shrink
Lacking nitrate
Normal Larger Larger Larger Larger Smaller /shrink
Lacking phosphorus
Normal Slightly larger
Slightly larger
Slightly larger
Slightly larger
Slightly larger
Lacking sulfate
Normal Larger Larger Larger Larger Larger
Lacking all nutrients
Normal Smaller /shrink
Smaller /shrink
Smaller /shrink
Smaller /shrink
Smaller /shrink
Table 1.5: observations on the shape of Lemna leaves
DISCUSSION
From the results, it is obvious that the lacking of iron has the least effect on the growth of
Lemna plants whereas the lacking of calcium has the most effect on the growth of Lemna
plants. This is because at the end of our observation, we found out that there is 4 Lemna
leaves left after 10 days for nutrient solution lacking calcium whereas there are 7 Lemna
leaves remaining for nutrient solution lacking iron. This means that iron is most probably a
micronutrient for the Lemna plant while for calcium, it is the macronutrient. Therefore,
calcium is one of the most important nutrients required by plants.
The lacking of nitrogen can cause chlorosis because nitrogen is essential for the formation of
amino acids, proteins, and chlorophyll. Chlorophyll is the pigment that keeps the plants green
in colour. The loss of chlorophyll can cause the colour of the leaves to turn yellow and
eventually decolourises. Furthermore, the growths of plants are retarded due to the lack of
protein which is essential for growth. Furthermore, the roots are also reducing in size and
dying. At the end of our observation, we found out that the leaflets decolourised and started
to decompose and there aren’t any roots visible. Magnesium is another vital component of
chlorophyll in plants. It is located in the central region of porphyrin head of chlorophyll,
where 4 nitrogen atoms are bonded to it.
This is a type of chlorophyll exist in every plant that shows the location of magnesium and
nitrogen inside it. Magnesium has variable oxidation states and can donate or accept
electrons. From the molecular formula shown, it is obvious that magnesium and nitrogen are
essential parts of chlorophyll. Without magnesium, chlorosis will also occur where the colour
of the leaves can turn yellow and eventually decolourised.
For the culture solution without iron minerals, the Lemna plants are not very much affected.
The plants even thrive in this condition and the number of leaves even greater than the plants
in complete culture solution although the size of leaves and roots are smaller. This shows that
the presence of iron may be needed by the plants in very small quantity but it can survive for
a long time without it. However, some yellow spots are noted on young leaves due to
chlorosis. This is most probably because iron still has some minor roles in the formation of
chlorophyll besides responsible for the respiration and metabolism of the plant. Iron is a
component of ferredoxin (iron sulphur proteins) that mediates electron transfer in light
dependent reactions in plants.
We also found out that there is no more Lemna plant survives in the nutrient solution lacking
calcium. Calcium plays the role in forming calcium pectate that function to hold the cells
together and also to form cell wall. So, without calcium, maybe the cell wall of the cells
cannot be formed perfectly thus the content of the cells will be leaking out. This can be
proven from our observation where the colour of the nutrient solution lacking calcium has
turned slightly green due to the leaking of the cell contents.
LIMITATIONS
In this experiment, there are still a few limitations can be detected that affects the experiment
and might cause the data to be different from its original value and thus, affecting the
reliability of the experiment.
Plant may be infected earlier before the experiment or their growth may be affected by other
factors. Besides that, the plant also may not get enough carbon dioxide because the plant was
covered with petri dish. So when many leaves have been produced, the demand for carbon
dioxide will be increase and this will affect their growth.
In addition, light intensity may not be constant because weather patterns always changing. As
on a rainy day, there may be no existence of sunlight and it will cause the nutrient solution in
the petri dishes can dry out at different rates. Furthermore, Carbon dioxide concentration and
temperature can also fluctuate due to changing weather patterns. Besides, each plant has its
own rate of photosynthesis. They have period where the activity of photosynthesis is very
high, usually in the afternoon and a period of low photosynthesis rate, usually at dawn.
The concentration of all the solutions are unknown and because of that it is fair to assume
that maybe some of the solutions have created a toxic environment to the Lemna plants. Thus
this results in the opposite phenomenon of mineral deficiency that is mineral toxicity or on
the simple words, excess of nutrients. This kind of accident also contributes to the abnormal
growth of plant.
There are many species of lemna and those many in size and features. Although in this
experiment we used only a species of lemna, the species is not really compatible with the
experiment. The observation of the lemna was hard to detect and this is due to limited
knowledge of the species. As a result, we spend more time to really observe the lemna
because it was too small and sometime there were some error occurs during the observation.
The Petri dishes are rinsed with water and wiped dry to prevent the fungal or bacterial
contamination. The contamination may damage the plant or making the plants deprived of
nutrients. Ensure that the Lemna plants do not adhere to the wall of the cover. If it is stick to
the wall of the cover, use a sterilised forceps to transfer it back to the nutrient solution. Avoid
finger from touching the nutrient solution and the plant to prevent contamination. After a few
days of observations, some water droplets may be found condensed on the cover. Wipe the
cover dry to give a clearer observation.
IMPROVEMENT
The experiment can be further improved by adding the nutrients solution whenever it has
lessened. This is to ensure the continuity supply of nutrients to the plants and the effect
appear on the plant growth is not affected by other mineral deficiency and it should be
affected alone by only one particular minerals. Greater number of plants should be used at the
initial experiment as better result can be obtained from a bigger size of the sample. Besides,
observation should be made under a microscope to detect any small chlorosis or necrosis
spots appear on the plant tissues.
A high resolution photograph could be taken everyday within the observation period as to be
aware to any changes that occur and also could be used for future reference and in comparing
it with one another. The experiment also could be conducted in a greenhouse to have better
control on the humidity and temperature factors that might affect the reliability of the results
obtained.
MEDICATION AND FURTHER WORKS
Other method that can be used to investigate the effects of plant minerals deficiencies is by
using different concentrations of minerals. For example, by using different range
concentrations of nitrogen ion and then observe the effects on the plants for a given period of
time. Also, when observe the colour of the leaves, magnifying lens can be used to obtain
bigger image. Light microscope can also be used to observe the colour of the pigments
contained on the leaves. This method also will lower the chance of miscount of the leaves.
The area of the Petri dishes were placed also need to be increases. The readings should also
be taken more than once to obtain the average as well as decrease the chance of error. Instead
of rinsing the Petri dishes with distilled water, it can be sterilized by boiling it but more work
has to be done.
Safety Precautions
The use of lab coat is important as to prevent clothes from being stained by the solutions
Delicate and fragile apparatus like beaker, measuring cylinder and the petri dish are also
taken into account during conducting the experiment
Be extra cautious when using sharp objects such as forceps when selecting and transferring
the Lemma plant into the petri dish containing nutrient solutions.
The nutrient solution must not be contaminated to ensure no other substances that consume
the particular nutrient. This will affect the growth of the lemma.
The solution must be closed properly with the cover to enhance the protection of the solution
All petri dishes must receive equal amount of sunlight. This is important to make sure the
light intensity is not the manipulating factors in this experiment and the location where all the
petri dishes were placed must also be fixed also based on the same reason.
Make sure the observation made based on average calculation. This will increase the
accuracy of the data. For instance, when we count the total number of leaves in a petri dish,
the counting should be done two or three times and get the average
The number of plantlets must be correctly recorded because there are new plantlets that are
very tiny and hard to find. All the lemma should not too close to each other to prevent
miscalculation.
Ensure that the Lemma plants do not adhere to the wall of the cover. If it is stick to the wall
of the cover, use a sterilised forceps to transfer it back to the nutrient solution.
Avoid finger from touching the nutrient solution and the plant to prevent contamination.
CONCLUSION
Mineral deficiencies in plants show different symptoms for particular mineral nutrients and it
affects the plant growth. Each of these mineral nutrients is essential for plants growth and has
its own function keeping the plants alive aand lacking of macronutrient minerals shows most
vice versa with lacking of micronutrient minerals. Experimental hypothesis is accepted.
REFERENCE
1. Plant nutrient- www.ncagr.gov/ cyber/kidswrld- accessed at 9 March 2012
2. Duckweed photo - www.cmuscmr.cmu.edu. - accessed at 9 March 2012
3. aquatics lemna - www.rook.org - accessed at 9 March 2012
4. programmes documents Duckweeds - www.ceh.ac.uksci- accessed at 10 March 2012
5. Edexcel AS Biology, Pearson Education Limited, 2008 - accessed at 10 March 2012
6. Campbell and Reece Biology Eighth edition, pg. 236 - accessed at 10 March 2012
MINERAL NUTRIENTS DEFICIENCY IN PLANTS
BY
NAME : ABDUL RAHMAN BIN MOHAMED
STUDENT ID : 2011894958
IC NUMBER : 930319-01-6807
LECTURER : SIR MOHD HAFIZ BIN ROTHI