Effect Of Synthetic Detergents On Vigna Growth Biology Essay

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Do different concentrations of different detergents (Tide and Surf Excel) affect the growth of root and shoot in Vigna Radiata (Mung bean)?

Abstract:

Plant growth is characterized by cell division and cell expansion along with the increase in the size of the cells. This growth is inhibited by the presence of certain toxic substances in the surrounding environment caused by damage at cellular levels. The present study reveals how different concentrations of different detergents (Tide and Surf Excel) affect the growth of root and shoot in Vigna Radiata (Mung bean).

This study was carried out by subjecting soaked green gram seeds (Vigna radiata) to three different environments. The seeds were allowed to grow in Control condition (Dechlorinated Tap water) and different concentrations of Surf Excel and Tide powder solutions (0.1% - 0.5%). The root and shoot lengths were noted after a time period of ten days.

It was found that the growth of both, the shoot and the root decreased as the concentration of both Surf Excel and Tide was increased. This was found out by comparing the mean lengths of both the shoot and the root grown in the control medium with those grown in Tide and Surf Excel solutions by conducting a 2 tail sample test. The results obtained showed a significant difference between all concentrations (0.1% - 0.5%) in comparisons between the control and the detergent solutions. However, when the two solutions were compared in terms of shoot growth with each other, a significant difference was only seen at 0.1% and 0.5% concentrations, while the shoot growth at all other concentrations (0.2%, 0.3% and 0.4%) showed no significant difference. In the case of root length, the significant difference was seen only in 0.1% concentration of solution between Tide and Surf Excel, while all other concentrations showed no significant difference. It was also interesting to note that Surf Excel relatively affected root growth more than Tide, while Tide relatively affected shoot growth more than Surf Excel.

CONTENTS

INTRODUCTION

Research Question

Consequences of Water Pollution

Detergents

Vigna Radiata (Mung bean)

Explanation of Research Question

MATERIALS AND METHOD

Materials Required

Hypothesis

Variables

Methodology

Procedure

Determination of Statistical Analysis

RESULTS

Mean Lengths of Shoot and Root in Surf Excel(Table and Graphs)

Mean Lengths of Shoot and Root in Tide Powder(Table and Graphs)

Values of t- test (Table and Graphs)

DISCUSSION AND SUMMARY

BIBLIOGRAPHY

APPENDIX

INTRODUCTION

Research Question: Do different concentrations of different detergents (Tide and Surf Excel) affect the growth of root and shoot in Vigna radiata (Mung bean)?

Nature has some of the most amazing stories to tell, the most breathtaking sights to show and sometimes, even the most mysterious of questions to ask. Somehow, though all life on earth has been created to be equally beautiful and unique in its own way, the plant kingdom is something that always has the most astounding of wonders, flowers that are synonymous with beauty, fields that personify heavenly scenery and gigantic trees that are only a minute reminder of nature's infinite power, are just the beginning of a long list of the incredible sights that the green kingdom beholds.

But as everything else in the world of today, these greeneries are also strongly hit by the one common and dramatically disastrous problem: POLLUTION!

Today the cry of pollution is heard from nooks and corners of the globe. Pollution has become a major threat to the very existence of not only to the mankind but also to all living organisms including plants. [1] 

Plants are living beings which exhibit the characteristic of growth like all other beings. The most essential and initial period of the growth stage of the plant is termed as germination. This process is affect based on the laundry effluents that drains into the land and the river system. The laundry effluent consists of detergent chemicals. These detergents in higher concentration destroy the plant growth. [2] 

Laundry detergents have long been associated with environmental degradation and pollution of water bodies. The fact that they have phosphates and sodium tri-polyphosphate (STTP), which are used to soften hard water for better washing, makes them environmentally unviable. In many countries around the world, phosphates have been banned as a detergent ingredient. India has no such regulations as yet, while the use of phosphates is not permitted [3] 

Consequences of Water Pollution

The various effects of water contamination are extensive and affect not only the environment, but human beings and animals as well. Water pollution affects major and minor water bodies like oceans, seas, rivers and lakes, sources of everyday drinking water, which makes it a prevalent universal issue. Its effect on humans can be briefed in the facts of the countless health issues that have been associated with water pollution.

As earlier stated, water is said to be contaminated when toxins, pathogens, chemicals or any other form of waste is present in it. So it is very easy to imagine the widespread effects of water pollution with all the contaminants disposed in it.

The effects of water pollution are copious; some can be short lived effects, which are recognized immediately, while others can be extremely invisible and long lived, and might take months or even years to show up. Some effects are listed below;

When chemical toxins enter the water, the toxins move from the water to the animals that drink it, this shows that marine pollution can be harmful to even outside species, like humans and birds that feed on the contaminated marine life or drink that water. This can also be lethal as such infections can enter food chains and harm organism at all levels

Water pollution can cause lethal diseases in humans and other animal species, like typhoid and cholera.

Acid rain, a form of water pollution caused by chemicals in rainfall, contains sulphate molecules, which can harm marine life in relatively smaller water bodies like lakes and ponds.

Contaminants in water bodies can affect their physical and chemical properties as a whole, for example, their conductivity, their temperatures and acidity etc. In such cases, varies water temperatures, due to pollution, can kill the aquatic life and affect the ecological balance in these water bodies.

Our main aim is to reproduce our polluted environment by scaling it down to using instruments which are practical and feasible enough to use in any laboratory.

Detergents

Detergents were introduced to the world in the 1920's and are relatively new to the cleaning industry having been about for only 85 years, but are far more popular than their predecessors: The Soaps; even though soaps have been around for more than 3,000 years. Originally manufactured during the onset of World War I in Germany, detergents have gained quick appeal since their prelim production. Detergent is defined as a cleansing substance that acts similarly to soap but is made from chemical compounds rather than fats and lye [4] . Modern detergents contain a chemical called a surfactant, which can be defined as "A substance capable of reducing the surface tension of a liquid in which it is dissolved." [5] 

Many of the detergents are phosphate based. Detergents with phosphate are a sustainable component. Phosphorus (P) is an essential element for all living organisms including plants. In man, phosphorus is necessary for human health. Phosphorus compounds make up the structure of bones and teeth and are fundamental to the transfer of energy within cells, and thus to all body functions, from thought through to motion. Phosphorus is an essential element in DNA (genetic material) and in many proteins. Phosphorus is naturally present in foods and is taken into the body as phosphates. In plants, phosphorus plays an essential role in photosynthesis and all energy recovering processes. Phosphates are also one of the main nutrients in almost all agricultural and garden fertilizers, because they are crucial for plant growth. If it increases in the land and enter the river or sea then it causes eutrophication leading to algal bloom and further destruction of the aquatic ecosystem [6] 

Detergents used

To redevelop the environmental pollution seen in aquatic systems in the natural environment to a smaller scale for laboratory experiments, I have used two different detergent solutions at different concentrations added to the plants, both of which have surfactant molecules having two parts. One is "water loving" and the other is "water hating." The water-loving (hydrophilic) part breaks the surface tension of water. The water-hating (hydrophobic) part is attracted to oil and grease in soils, loosening and removing them from fabrics. Detergents usually contain more than one type of surfactant to address the needs of removing certain types of soils and cleaning different types of fabrics. [7] 

Tide Powder: A heavy-duty enzyme detergent powder

Surf Excel: A heavy duty enzyme detergent bar

Deteregent Ingredients

Bleach Activator

         Nonanoyloxybenzenesulfonate

Chelant

         Diethylenetriamine Pentaacetate (Sodium Salt)

Dispersant

         Sodium Polyacrylate

Enzyme

         Protease

Oxygen Bleach

         Sodium Percarbonate

Process Aid

         Palmitic Acid

         Sodium Sulfate

         Water

Removes Water Hardness

         Sodium Aluminosilicate

         Sodium Carbonate

Stabilizer

         Polyethylene Glycol 4000

Suds Suppressor

         Silicone

Surfactant

         Alkyl Sulfate

         Linear Alkylbenzene Sulfonate

Whitening Agent

         Disodium Diaminostilbene Disulfonate

Vigna Radiata (Mung Bean)

The Mung bean is the name of the gram seed Vigna radiata, an ovoid, greenish brown dicot which is native to parts of Bangladesh, Pakistan and India. The gram seed (Mung), as a species was recently shifted from the genus Phaseolus to the genus Vigna but is still cited as Phaseolus aureus or Phaseolus adiates in some cases.

Plant Taxonomy [8] 

Kingdom: Plantae

Division: Magnoliophyta

Class: Magnoliopsida

Order: Fabales

Family: Fabaceae

Genus: Vigna

Species: V. radiata

History of Plant [9] 

The history of this sprout can be dated to thousands of years ago, first discovered in Asia, the bean has been grown in Chinese pastures for well over 3,000 years. Keeping put to the easy farming techniques that were required back then, cultivators grow these using very little or no machinery . As of now, India and China are the chief manufacturers of these seeds.

Climate and Soil [10] 

Mung beans are chiefly produced in South-East Asia but are also cultivated on smaller scales in hot and dry regions of South Europe and Southern USA. In India and Bangladesh, they are grown during two seasons. One is the Rabi season (starting November), and the other is the Kharif season (starting June). Mung beans are tropical (or sub-tropical) crops, and require warm temperatures (optimally round 30-35°C). Loamy soil is best for pusap cultivation.

Nutritional Values

Mung beans are a good source of Vitamins A, B, C & E, calcium, iron, magnesium, potassium, and amino acids. Mung beans contain 20% protein and are a good source of foliate and dietary fibre. The nutritional values of the raw mature mung seed is given in a table below [11] 

Nutritional value per 100 g (3.5 oz)

Energy

1,452 kJ (347 kcal)

Carbohydrates

62.62 g

Sugars

6.60 g

Dietary fiber

16.3 g

Fat

1.15 g

Protein

23.86 g

Vitamin C

4.8 mg (8%)

Calcium

132 mg (13%)

Magnesium

189 mg (51%)

Phosphorus

367 mg (52%)

Potassium

1246 mg (27%)

Sodium

15 mg (1%)

Percentages are relative to US recommendations for adults.

Source: USDA Nutrient database

Explanation of Research Question

Do different concentrations of different detergent affect the growth of root and shoot in Vigna Radiata (Mung bean)?

This question mainly addresses the topic of stunted growth of plants. Detergents contain powerful surfactants like sodium dodecyl sulfate, which routinely aggregate lipids and denature proteins. When these surfactant bearing detergents are absorbed by a plant, these molecules cause cell membranes to disintegrate and membranes to lose their primary functions. This can cause a part or sometimes even ALL of the plant to die. [12] 

Depending on the various concentrations of these pollutants, the plant shows different levels of growth, ascending from the least growth in the most concentrated of solutions (0.5%) to the highest in pure distilled water.

The present study is undertaken to find out the effects of detergent on growth of plants that are subjected to these detergents.

Materials and Methods

Materials Required

Surf Excel

Tide washing powder

Measuring Cylinders (50 ml)

2 Beakers (50 ml),

Petri dishes (50)

Green gram seeds (Mung bean - 100 grams)

Dropper

2 Pipettes (5 ml and 1 ml)

Dechlorinated Tap water

Hypothesis:

Null Hypothesis (H0): The detergents Tide and Surf Excel will not reduce the growth of the root and shoot in Vigna Radiata.

Positive Hypothesis (H1): The detergents Tide and Surf Excel will reduce the growth of the root and shoot in Vigna Radiata.

Variables:

Control

Number of seeds per petri dish (10)

Number of petri dishes per concentration (5)

Time period for plant growth (10 days)

Room temperature

Amount of solution in each petri dish

Independent

The concentration of detergents (Tide and Surf Excel) in solution (0.1% to 0.5%)

Dependent

The length of the shoot in Vigna radiata (in cms)

The length of the root in Vigna radiata (in cms)

Methodology

Preparation of different concentrations of Surf Excel and Tide solution

Take 1000 ml of water, and add 10 grams of Surf excel powder to it. Stir the solution until the powder completely dissolves. This will give the 0.1% Surf solution.

Repeat the same with 1000 ml and 20 grams to give 0.2% and keep repeating until all five solutions, the last being 50 grams in 1000 ml (0.5%), are ready.

Repeat the same procedure with Tide powder to obtain different concentrations of Tide solution (0.1% - 0.5%)

Procedure

Growth of Shoot and Root of Vigna Radiata in normal water condition (Control)

The petri dishes were sterilized and placed separately containing cotton along with Dechlorinated tap-water.

Then ten soaked viable seeds were placed in each petri dish.

The setup was left for 10 days and was regularly monitored by watering.

Then the growth of the root and shoot of the plant was observed and noted after 10th day.

The above mentioned procedure was considered to be as control.

Growth of Shoot and Root of Vigna Radiata in Surf Excel

The petri dishes were sterilized and placed separately containing cotton along with the different concentrations of Surf Excel solution earlier created.

Then ten soaked viable seeds were placed in each of the five petri dishes containing Surf Excel solution of concentration 0.1%

The same was repeated for the other four concentrations (0.2% to 0.5%)

The setup was left for 10 days and was regularly monitored by watering with different concentrated solutions.

Then the growth of the root and shoot of the plant was observed and noted after 10th day.

Growth of Shoot and Root of Vigna Radiata in Tide Powder

The petri dishes were sterilized and placed separately containing cotton along with the different concentrations of Tide Powder solution earlier created.

Then ten soaked viable seeds were placed in each of the five petri dishes containing Tide solution of concentration 0.1%

The same was repeated for the other four concentrations (0.2% to 0.5%)

The setup was left for 10 days and was regularly monitored by watering with different concentrated solutions.

Then the growth of the root and shoot of the plant was observed and noted after the 10th day.

Determination of Statistical Analysis

The experimental setup was observed for a period of ten days, after which the mean and standard deviations for all the concentrations were calculated according to the given formulae;

Mean was calculated using,

The standard deviation was calculated

The means, along with standard deviations and the number of trials were taken to calculate the t values, using a two tailed sample t test.

RESULTS

Growth of Shoot and root in Vigna radiata

In the control condition (Dechlorinated tap water) the mean length of Shoot and root was recorded as 11.6 ± 1.58cm and 3.35 ± 0.75cm.

Table 1:

Growth of Shoot and root length in Vigna radiata (Control)

S.No.

Length of Shoot (cms)

Length of Root (cms)

1

10

3

2

11

4

3

12

4

4

11

3

5

14

4

6

9

2

7

12

3

8

14

4.5

9

12

3

10

11

3

Mean

11.6 ± 1.58

3.35 ± 0.75

s

In the case of the seeds grown in Surf Excel, the mean length of both the shoot and the root keeps declining from 5.09 ± 0.97cm and 0.54 ± 0.12cm respectively in 0.1% detergent concentration to 0.07 ± 0.1cm and 0cm respectively in 0.5% detergent concentration.

Table 2:

Mean Lengths of Shoot and Root in Surf Excel (Tables and Graphs)

Concentration [%]

Mean Length of Shoot (cms)

Mean Length of Root (cms)

0.1%

5.09 ± 0.97

0.54 ± 0.12

0.2%

2.09 ± 0.83

0.23 ± 0.09

0.3%

1.19 ± 0.45

0.16 ± 0.06

0.4%

0.35 ± 0.31

0.04 ± 0.06

0.5%

0.07 ± 0.1

0

Similarly, in the case of the seeds grown in Tide, the mean length of both the shoot and the root keeps declining from 2.96 ± 0.74cm and 0.76 ± 0.23cm respectively in 0.1% detergent concentration to 0cm and 0cm respectively in 0.5% detergent concentration.

Table 3

Mean Lengths of Shoot and Root in Tide Powder

Concentration [%]

Mean Length of Shoot (cms)

Mean Length of Root (cms)

0.1%

2.96 ± 0.74

0.76 ± 0.23

0.2%

1.82 ± 0.21

0.33 ± 0.14

0.3%

0.95 ± 0.19

0.19 ± 0.11

0.4%

0.21 ± 0.16

0.02 ± 0.04

0.5%

0

0

Analysis and Interpretation

T- Value table for Shoot in Vigna radiata

S. No.

Concentration

Comparison

Calculated T - Value

Table t - Value

1

0.1%

Control and Surf

11.10

2.10

2

0.2%

Control and Surf

16.85

3

0.3%

Control and Surf

20.04

4

0.4%

Control and Surf

22.09

5

0.5%

Control and Surf

23.08

6

0.1%

Control and Tide

15.66

7

0.2%

Control and Tide

19.40

8

0.3%

Control and Tide

21.16

9

1

0.4%

Control and Tide

22.61

10

0.5%

Control and Tide

23.22

11

0.1%

Tide and Surf Excel

5.5208

12

0.2%

Tide and Surf Excel

0.9973

13

0.3%

Tide and Surf Excel

1.5537

14

0.4%

Tide and Surf Excel

1.2691

15

0.5%

Tide and Surf Excel

22.1359

For Root in Vigna radiata

S. No.

Concentration

Comparison

Calculated T - Value

Table t - Value

1

0.1%

Control and Surf

11.70

2.10

2

0.2%

Control and Surf

13.06

3

0.3%

Control and Surf

13.40

4

0.4%

Control and Surf

13.91

5

0.5%

Control and Surf

14.12

6

0.1%

Control and Tide

10.44

7

0.2%

Control and Tide

12.51

8

0.3%

Control and Tide

13.18

9

1

0.4%

Control and Tide

14.02

10

0.5%

Control and Tide

14.12

11

0.1%

Tide and Surf Excel

2.6817

12

0.2%

Tide and Surf Excel

1.9000

13

0.3%

Tide and Surf Excel

0.7571

14

0.4%

Tide and Surf Excel

0.8771

15

0.5%

Tide and Surf Excel

0

Comparisons of Mean Shoot length of Vigna radiata

Comparisons of Mean Shoot length of Vigna radiata

Interpretation

Testing Hypothesis

Comparison of the effects of Control and Surf Excel solutions on shoot:

In the comparison between Control and Surf excel solutions at 0.1% concentrations, the t value obtained was 11.10 at 18 degree of freedom [p = 0.05] which is more than the table t value, therefore the positive hypothesis is accepted. This result indicates that the plant is affected by Surf excel as it reduces the growth of shoot in Vigna Radiata at 0.1%

Likewise, similar results are observed for comparisons regarding all concentrations between Surf Excel and Control, where the t value is seen to be higher than the table t value for all cases (0.1% - 0.5%). This result indicates that the plant is affected by Surf excel as it reduces the growth of shoot in Vigna Radiata at any concentration from that of its growth in control.

Comparison of the effects of Control and Tide solutions on shoot:

In the comparison between Control and Tide solutions at 0.1% concentrations, the t value obtained was 15.66 at 18 degree of freedom [p = 0.05] which is more than the table t value, therefore the positive hypothesis is accepted. This result indicates that the plant is affected by Tide as it reduces the growth of shoot in Vigna Radiata at 0.1%

Likewise, similar results are observed for comparisons regarding all concentrations between Tide and Control, where the t value is seen to be higher than the table t value for all cases (0.1% - 0.5%). This result indicates that the plant is affected by Tide as it reduces the growth of shoot in Vigna Radiata at any concentration from that of its growth in control.

Comparison of the effects of Surf Excel and Tide solutions on shoot:

In the comparison between Surf Excel and Tide solutions at 0.1% concentration, the t value obtained was 5.520 at 18 degree of freedom [p = 0.05] which is more than the table t value, therefore we can say that Tide solution affects shoot growth at a relatively higher level than Surf Excel at 0.1% concentration.

However, when comparisons concerning concentrations ranging from 0.2% to 0.4% were made, the t values obtained were 0.99, 1.55 and 1.27, all of which are lower than the table t value, which helps us conclude that at solutions of concentration 0.2%, 0.3% and 0.4%, Tide and Surf Excel are more or less equally harmful to shoot growth in Vigna Radiata.

Interestingly, at 0.5% solution concentration the t value obtained was 22.13, which is much higher than the table t value, which states that at 0.5% solution concentration, Tide affects the shoot growth in Vigna Radiata much more than the Surf Excel solution of the same concentration.

Comparison of the effects of Control and Surf Excel solutions on root:

In the comparison between Control and Surf excel solutions at 0.1% concentrations, the t value obtained was 11.70 at 18 degree of freedom [p = 0.05] which is more than the table t value, therefore the positive hypothesis is accepted. This result indicates that the plant is affected by Surf excel as it reduces the growth of root in Vigna Radiata at 0.1%

Likewise, similar results are observed for comparisons regarding all concentrations between Surf Excel and Control, where the t value is seen to be higher than the table t value for all cases (0.1% - 0.5%). This result indicates that the plant is affected by Surf excel as it reduces the growth of root in Vigna Radiata at any concentration from that of its growth in control.

Comparison of the effects of Control and Tide solutions on root:

In the comparison between Control and Tide solutions at 0.1% concentrations, the t value obtained was 10.44 at 18 degree of freedom [p = 0.05] which is more than the table t value, therefore the positive hypothesis is accepted. This result indicates that the plant is affected by Tide as it reduces the growth of root in Vigna Radiata at 0.1%

Likewise, similar results are observed for comparisons regarding all concentrations between Tide and Control, where the t value is seen to be higher than the table t value for all cases (0.1% - 0.5%). This result indicates that the plant is affected by Tide as it reduces the growth of root in Vigna Radiata at any concentration from that of its growth in control.

Comparison of the effects of Surf Excel and Tide solutions on root:

In the comparison between Surf Excel and Tide solutions at 0.1% concentration, the t value obtained was 2.68 at 18 degree of freedom [p = 0.05] which is more than the table t value, therefore we can say that Surf Excel solution affects root growth at a relatively higher level than Tide at 0.1% concentration.

However, when comparisons concerning concentrations ranging from 0.2% to 0.5% were made, the t values obtained were 1.9, 0.75, 0.87 and 0 respectively, all of which are lower than the table t value, which helps us conclude that at solutions of concentration 0.2%, 0.3%, 0.4% and 0.5%, Tide and Surf Excel are more or less equally harmful to root growth in Vigna Radiata.

DISCUSSION

We have earlier noted that detergents contain powerful molecules called surfactants which help in effectively removing stains and dirt as they lower the surface tension of the liquid (usually water) in which they are mixed. This ingredient is noted to cause the most damage to plants because this causes the detergent to not truly dissolve; this is because these form aggregates (called micelles) in the water, not individual molecules. The lowered surface tension allows the solution of the detergent to spread out on the plant [13] 

The present results revealed that increasing detergent concentration in the water solution caused deteriorative growth of Vigna radiata. The results derived from the present study showed that both Surf and Tide caused decreased growth in both the shoot and root of the plant. This can be validated by taking a look at the calculated t values that we have derived by comparing our control Studies have proven that surfactants like Alkyl sulfate and Linear Alkylbenezene sulfonate, which constitute as the main ingredients in the studied detergents (Surf and Tide), cause the cell membrane to lose its integrity by routinely aggregating lipids and denaturing proteins.

When these surfactant bearing detergents are absorbed by a plant, these molecules cause cell membranes to disintegrate and membranes to lose their primary functions. Surfactants have been reported to distress a variety of effects in plant activities like photophosphorylation, protoplasmic streaming and mitosis. But the one that the present study can best relate to is the effect of surfactants on the elongation of primary roots and root hair.

Surfactants have been known to cause stunted growth in shoots and roots of plants, a massive example of which lies right in nature, in the countless trees and plants hit by water pollution along lakes and rivers where untreated industrial wastes are dumped, causing diminutive growth or even death of these greeneries.

BIBLIOGRAPHY

Woodwell, G.M. 1970. Effect of pollution on the structure and physiology of ecosystem. Science 1668 (3930): 429-433

Edward, R.W. 1972. Pollution. Oxford Biology. Reader No. 31, Oxford Univ. Press, London.

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