Flower Production - Unit 3 | Production Technology of Cut Flowers | Horticulture

HORMI - 202

Production Technology of Cut Flowers
UNIT III

📚 Contents

Flower Production:-
1. Water and Nutrient Management
2. Fertigation
3. Weed Management
4. Rationing, Training and Pruning
5. Disbudding and Special Practices
6. Use of Growth Regulators
7. Physiological Disorders
8. IPM and IDM
9. Production for Exhibition

Water and Nutrient Management

1. Importance of Water and Nutrient Management in Cut Flowers

Water and nutrient management is a critical component of commercial cut flower production, as it directly influences vegetative growth, flower initiation, stem length, flower size, colour intensity, vase life, and overall market quality. Improper water or nutrient supply is one of the major causes of poor flower quality and low productivity in floriculture (Arora, 2006 and Bhattacharjee, 2006).

• Ensures continuous and uniform growth
• Improves nutrient use efficiency
• Reduces physiological disorders
• Essential for protected and high-tech floriculture

2. Water Management in Cut Flower Production

2.1 Role of Water

• Maintains cell turgidity and stem rigidity
• Facilitates nutrient transport and photosynthesis
• Regulates transpiration and cooling
• Essential during bud initiation and flower development stages

2.2 Water Requirement

Water requirement varies depending on:

• Crop species (rose > carnation > chrysanthemum)
• Growth stage (higher during flowering)
• Climate and season
• Soil type and growing media

Crop	Relative Water Requirement
Rose	High
Gerbera	Moderate to High
Carnation	Moderate
Gladiolus	Moderate

2.3 Irrigation Methods

• a) Surface Irrigation: Traditional method (furrow or basin). Low efficiency, higher water loss. Not recommended for high-quality cut flowers.
• b) Drip Irrigation (Recommended): Supplies water directly to root zone. Saves 30–50% water. Reduces disease incidence. Ideal for protected cultivation.
• c) Sprinkler Irrigation: Used in open field cultivation. Can increase humidity and disease pressure.

3. Nutrient Management in Cut Flowers

3.1 Essential Nutrients

Cut flowers require both macronutrients and micronutrients in balanced proportion for optimum growth and flowering (Chadha, 1995).

Macronutrients

• Nitrogen (N) – Vegetative growth, leaf area
• Phosphorus (P) – Root growth, bud initiation
• Potassium (K) – Flower quality, stem strength, vase life
• Calcium (Ca) – Cell wall strength, prevents stem breakage
• Magnesium (Mg) – Chlorophyll formation

Micronutrients

• Iron (Fe) – Chlorophyll synthesis
• Zinc (Zn) – Enzyme activity
• Boron (B) – Flower development and pollen viability
• Manganese (Mn), Copper (Cu), Molybdenum (Mo)

3.2 Nutrient Demand at Different Growth Stages

Growth Stage	Nutrient Requirement
Vegetative growth	High Nitrogen
Bud initiation	Higher Phosphorus
Flower development	High Potassium and Calcium

4. Integrated Water and Nutrient Management

• Soil and water testing before fertilizer application
• Split application of fertilizers
• Avoid excessive nitrogen to prevent soft stems and poor vase life
• Use of chelated micronutrients under protected cultivation

5. Problems Due to Improper Water and Nutrient Management

• Excess water → Root rot, fungal diseases
• Water stress → Bud drop, poor flower size
• Excess nitrogen → Weak stems, delayed flowering
• Potassium deficiency → Poor colour and reduced vase life

6. Conclusion

Efficient water and nutrient management forms the foundation of successful cut flower production. Precision in irrigation and nutrient supply is essential to achieve high yield, superior quality, and export-grade flowers, especially under protected cultivation systems (Prasad & Kumar, 2003 and Reddy et al., 2007).

Fertigation

1. Concept of Fertigation

Fertigation is the technique of applying water-soluble fertilizers through the irrigation system, mainly via drip irrigation. It allows precise, timely, and efficient supply of nutrients directly to the root zone of cut flower crops. Fertigation is a core component of modern and high-tech floriculture (Prasad & Kumar, 2003 and Reddy et al., 2007).

2. Advantages of Fertigation in Cut Flowers

• Higher nutrient use efficiency (up to 80–90%)
• Uniform nutrient distribution
• Reduced fertilizer losses through leaching
• Improved flower quality and yield
• Suitable for protected cultivation and soilless media
• Lower labour requirement

3. Fertigation Systems Used

3.1 Drip Fertigation System

• Most commonly used system
• Fertilizers are injected into drip lines
• Ensures direct nutrient availability to roots

3.2 Fertilizer Injection Devices

• Venturi injector – Simple, low-cost, widely used
• Fertilizer tank – Suitable for small units
• Positive displacement pumps – Accurate, used in commercial greenhouses

4. Fertilizers Used in Fertigation

4.1 Characteristics of Fertigation Fertilizers

• Completely water soluble
• Free from impurities
• Compatible with irrigation system
• Low salt index

4.2 Common Fertilizers

Nutrient	Fertilizer Source
Nitrogen	Urea, Calcium nitrate, Potassium nitrate
Phosphorus	Phosphoric acid, Mono ammonium phosphate (MAP)
Potassium	Potassium nitrate, Potassium sulphate
Calcium	Calcium nitrate
Micronutrients	Chelated Fe, Zn, Mn, Cu, B

5. Fertigation Scheduling

Fertigation schedule depends on crop, growth stage, and growing environment.

Growth Stage	Nutrient Emphasis
Establishment	Balanced N:P:K (1:1:1)
Vegetative growth	Higher Nitrogen
Bud initiation	Higher Phosphorus
Flower development	Higher Potassium & Calcium

• Applied in small, frequent doses
• Daily or alternate-day fertigation preferred

6. Fertigation in Soilless and Protected Cultivation

• Nutrient solution EC and pH must be monitored regularly
• Ideal pH: 5.5–6.5
• Ideal EC: 1.0–2.0 dS/m (crop specific)
• Drainage water analysis helps avoid salt accumulation

7. Problems and Precautions

• Clogging of emitters due to poor-quality fertilizers
• Salt accumulation if EC not monitored
• Over-fertigation leading to soft stems and poor vase life
• Regular flushing of drip lines is essential

8. Conclusion

Fertigation is a highly efficient nutrient management technique for cut flowers. It plays a vital role in achieving uniform growth, superior flower quality, and higher economic returns, especially in high-tech and protected floriculture systems.

Weed Management in Cut Flowers

1. Importance of Weed Management

Weeds are unwanted plants that compete with cut flower crops for water, nutrients, light, and space. In floriculture, weed infestation leads to poor flower quality, reduced yield, harvesting difficulties, and increased pest and disease incidence. effective weed control is essential for profitable cut flower production (Bose & Yadav, 1989 and Chadha & Chaudhury, 1992).

2. Major Problems Caused by Weeds

• Competition for nutrients and moisture
• Reduced flower size and stem length
• Harbouring of insect pests and pathogens
• Interference in cultural operations and harvesting
• Reduced aesthetic value of flower beds

3. Critical Period of Weed Competition

The first 30–45 days after planting is the most critical period for weed competition in most cut flower crops. Uncontrolled weeds during this stage can cause irreversible yield loss.

4. Weed Management Methods

4.1 Cultural Methods

• Proper land preparation and leveling
• Use of weed-free planting material
• Crop rotation to break weed life cycles
• Optimum plant spacing for quick canopy cover

4.2 Mechanical Methods

• Hand weeding and hoeing
• Shallow cultivation to avoid root damage
• Labour intensive but safe for flowers

4.3 Mulching

• Organic mulches: straw, dry leaves, sawdust
• Inorganic mulches: black polyethylene film
• Reduces weed emergence and conserves moisture
• Widely used in rose and gerbera cultivation

5. Chemical Weed Control

Chemical weed control should be used cautiously in cut flowers due to phytotoxicity risks.

5.1 Pre-emergence Herbicides

Herbicide	Crop	Remarks
Pendimethalin	Rose, Gladiolus	Controls annual grasses and broad-leaved weeds
Alachlor	Chrysanthemum	Applied immediately after planting

5.2 Post-emergence Herbicides

• Rarely recommended
• Only selective herbicides at low doses
• Spot application preferred

6. Weed Management in Protected Cultivation

• Use of sterilized soil or soilless media
• Polyethylene mulching is most effective
• Drip irrigation reduces weed emergence
• Manual removal of occasional weeds

7. Integrated Weed Management (IWM)

• Combination of cultural, mechanical, and chemical methods
• Minimizes herbicide dependence
• Environmentally safe and economically viable

8. Conclusion

Effective weed management is essential to achieve high-quality cut flowers. Integrated weed management ensures healthy crop growth, better flower yield, and ease of cultivation.

Rationing, Training and Pruning

1. Rationing in Cut Flowers

1.1 Concept of Rationing

Rationing refers to the regulation of the number of flowers, shoots, or buds allowed to develop on a plant in order to obtain high-quality blooms. In commercial floriculture, producing fewer but superior flowers is more profitable than producing a large number of poor-quality blooms. (Bose et al., 1999 and Prasad & Kumar, 2003).

1.2 Objectives of Rationing

• Improve flower size and colour
• Increase stem length and thickness
• Ensure uniform flowering
• Reduce the exhaustion of plants

1.3 Crops Where Rationing is Important

• Rose
• Carnation
• Chrysanthemum
• Gerbera

2. Training of Cut Flower Crops

2.1 Definition

Training is the practice of guiding and supporting plant growth to develop a desired shape and structure, ensuring better light penetration, air circulation, and ease of cultural operations.

2.2 Objectives of Training

• Efficient utilization of space
• Better exposure of leaves to light
• Prevention of lodging and stem bending
• Improved flower quality and yield

2.3 Training Systems in Cut Flowers

• a) Net Training: Widely used in carnation, chrysanthemum, and gerbera. Plastic or nylon nets are provided at different heights. Prevents bending and improves stem straightness.
• b) Staking: Individual support using bamboo sticks or wires. Used in gladiolus and lilium.
• c) Arching (in Roses): Bending of non-flowering shoots towards the base. Improves photosynthesis and promotes new flowering shoots. Important practice in greenhouse rose cultivation.

3. Pruning in Cut Flowers

3.1 Definition

Pruning is the selective removal of unwanted or excess plant parts such as shoots, branches, or old flowers to regulate growth and flowering. It is a key practice in perennial cut flower crops.

3.2 Objectives of Pruning

• Maintain plant shape and vigour
• Stimulate new shoot emergence
• Regulate flowering time
• Remove diseased or dead plant parts

3.3 Types of Pruning

Type	Description	Crop
Light pruning	Removal of weak shoots	Rose
Moderate pruning	Removal of 1/3rd shoot length	Rose, Chrysanthemum
Hard pruning	Severe cutting back	Rose (rejuvenation)

3.4 Pruning in Important Cut Flowers

• Rose: Annual pruning to regulate flushes and flower quality
• Chrysanthemum: Pruning after flowering to promote new shoots
• Carnation: Removal of old flowering shoots after harvest

4. Precautions During Training and Pruning

• Use sharp and sterilized tools
• Avoid pruning during extreme weather
• Apply fungicide paste on large cuts if required
• Ensure proper nutrition after pruning

5. Conclusion

Rationing, training, and pruning are essential cultural practices that directly influence flower quality and productivity. Systematic application of these practices ensures strong plants, uniform flowering, and higher economic returns in commercial cut flower production (Bose & Yadav, 1989; Chadha, 1995).

Disbudding and Special Horticultural Practices

1. Disbudding in Cut Flowers

1.1 Definition

Disbudding is the selective removal of excess or unwanted flower buds to regulate flowering and improve the quality of the remaining blooms. This practice is widely recommended in commercial floriculture (Bose & Yadav, 1989; Chadha, 1995).

1.2 Objectives of Disbudding

• Produce large-sized, high-quality flowers
• Improve stem thickness and strength
• Ensure uniformity in flower size and shape
• Direct plant energy towards selected buds

1.3 Types of Disbudding

• a) Single Bud Disbudding: Removal of all lateral buds, retaining only the terminal bud. Produces one large flower per stem. Common in standard roses and standard carnations.
• b) Multiple Bud Disbudding: Removal of the terminal bud, retaining lateral buds. Produces spray-type flowers. Common in spray carnations and spray chrysanthemums.

1.4 Crop-wise Importance

Crop	Disbudding Practice
Rose	Single bud for exhibition and export quality
Carnation	Single or spray type depending on market
Chrysanthemum	Terminal or lateral bud removal

2. Special Horticultural Practices in Cut Flowers

Special horticultural practices are crop-specific techniques adopted to enhance flower quality, regulate growth, and increase economic returns (Bhattacharjee, 2006).

• 2.1 Pinching: Removal of apical growing point. Breaks apical dominance and promotes lateral branching. Used in chrysanthemum, carnation, and marigold.
• 2.2 Deshooting: Removal of excess vegetative shoots. Improves air circulation and light penetration. Important in rose and carnation cultivation.
• 2.3 Bending (Arching) in Roses: Bending of non-flowering shoots towards ground level. Enhances photosynthesis. Promotes new basal flowering shoots. Essential practice in greenhouse roses.
• 2.4 Earthing Up: Covering the base of plants with soil. Provides support and improves root growth. Common in gladiolus and tuberose.
• 2.5 Removal of Spent Flowers: Prevents energy loss in seed formation. Encourages continuous flowering. Important in rose and gerbera.
• 2.6 Use of Support Systems: Horizontal netting and vertical supports. Prevents lodging and stem bending. Essential for long-stemmed flowers.

3. Advantages of Disbudding and Special Practices

• Improved flower size and appearance
• Higher market and export value
• Better plant health and longevity
• Efficient utilization of nutrients and water

4. Conclusion

Disbudding and special horticultural practices play a crucial role in determining the quality of cut flowers. Systematic adoption of these practices ensures premium-quality blooms, uniform flowering, and higher profitability in commercial floriculture. (Prasad & Kumar, 2003; Reddy et al. 2007).

Use of Growth Regulators in Cut Flowers

1. Introduction

Plant Growth Regulators (PGRs) are organic compounds, other than nutrients, which in small quantities modify physiological processes of plants. In cut flower production, growth regulators are extensively used to control growth, induce or delay flowering, improve flower quality, regulate plant architecture, and enhance post-harvest life. (Arora, 2006; Bhattacharjee, 2006; Chadha, 1995).

2. Objectives of Using Growth Regulators

• Regulate vegetative and reproductive growth
• Induce early or off-season flowering
• Improve flower size, colour, and stem length
• Control plant height and branching
• Delay senescence and increase vase life

3. Major Groups of Growth Regulators and Their Role

3.1 Auxins

• Promote cell elongation and root initiation
• Used mainly in vegetative propagation

Auxin	Crop	Effect
IBA / NAA	Rose, Carnation	Improves rooting of cuttings

3.2 Gibberellins (GA)

• Promote stem elongation and flowering
• Break dormancy of bulbs and corms

Crop	GA3 Dose	Effect
Gladiolus	100–150 ppm (corm soak)	Early and uniform flowering
Carnation	50–100 ppm (spray)	Stem elongation
Rose	100 ppm	Increased flower production

3.3 Cytokinins

• Promote cell division and lateral bud growth
• Delay leaf and flower senescence

Cytokinin	Effect
Benzyl Adenine (BA)	Improves branching and delays senescence
Kinetin	Enhances flower longevity

3.4 Ethylene and Ethylene Releasing Compounds

• Ethylene promotes senescence and abscission
• Used carefully to regulate flowering in specific crops

Chemical	Crop	Effect
Ethephon	Chrysanthemum	Induces flowering and uniformity

3.5 Growth Retardants

• Reduce excessive vegetative growth
• Promote compact plants with strong stems

Retardant	Crop	Effect
Paclobutrazol	Gerbera, Rose	Controls plant height, improves flower quality
Daminozide (B-Nine)	Carnation, Chrysanthemum	Short internodes, better form

4. Methods of Application

• Foliar spray
• Soil drenching
• Bulb or corm soaking
• Dip treatment of cuttings

5. Precautions in Use of Growth Regulators

• Correct concentration is critical to avoid phytotoxicity
• Apply during cooler parts of the day
• Avoid mixing incompatible chemicals
• Use protective equipment

6. Conclusion

Growth regulators are powerful tools in modern cut flower production. Judicious use of PGRs helps achieve controlled growth, superior flower quality, synchronized flowering, and enhanced commercial returns. (Bhattacharjee, 2006; Reddy et al., 2007).

Physiological Disorders and Their Remedies in Cut Flowers

1. Introduction

Physiological disorders are abnormalities in plant growth and development caused by non-pathogenic factors such as nutrient imbalance, water stress, temperature extremes, light deficiency, or improper cultural practices. In cut flowers, these disorders severely affect flower quality, yield, marketability, and vase life. (Bose et al., 1999; Chadha, 1995; Prasad & Kumar, 2003).

2. Causes of Physiological Disorders

• Imbalanced nutrition (macro- and micronutrients)
• Water stress (deficit or excess)
• Temperature extremes
• Low or excessive light intensity
• High salinity or improper pH
• Improper use of growth regulators

3. Common Physiological Disorders in Cut Flowers

3.1 Blind Shoots (Rose)

Symptoms: Shoots fail to produce flower buds; remain vegetative.
Causes: Low light intensity, nutrient imbalance, low temperature, weak shoots.
Remedies:

• Improve light penetration
• Balanced fertilization
• Removal of blind shoots
• Application of GA₃ (50–100 ppm)

3.2 Bud Drop (Rose, Gerbera, Carnation)

Symptoms: Flower buds drop before opening.
Causes: Moisture stress, low humidity, boron deficiency, high temperature.
Remedies:

• Maintain uniform soil moisture
• Maintain RH at 60–70%
• Foliar spray of boron (0.2%)

3.3 Bent Neck (Rose)

Symptoms: Flower stalk bends just below the flower head after harvest.
Causes: Calcium deficiency, weak stem tissues, improper water uptake.
Remedies:

• Calcium supplementation (calcium nitrate)
• Harvest at proper stage
• Immediate hydration after harvest

3.4 Flower Deformity

Symptoms: Misshapen or malformed flowers.
Causes: Temperature fluctuations, excessive nitrogen, improper PGR use.
Remedies:

• Maintain optimal temperature
• Avoid excess nitrogen
• Apply growth regulators judiciously

3.5 Chlorosis

Symptoms: Yellowing of leaves, especially young leaves.
Causes: Iron or magnesium deficiency, high soil pH.
Remedies:

• Apply chelated iron or magnesium sulphate
• Correct soil pH

3.6 Split Calyx (Carnation)

Symptoms: Calyx splits during flower opening.
Causes: Rapid growth due to excess nitrogen, high temperature, moisture imbalance.
Remedies:

• Balanced nitrogen supply
• Maintain optimal temperature
• Use calyx-support clips

4. General Preventive Measures

• Balanced and stage-wise nutrient management
• Regular soil and water testing
• Proper irrigation scheduling
• Maintaining optimal environmental conditions
• Careful use of growth regulators

5. Conclusion

Physiological disorders significantly reduce the quality and profitability of cut flower crops if not managed properly. Understanding the causes and adopting appropriate corrective measures helps ensure healthy plants, superior flower quality, and consistent production (Chadha & Chaudhury, 1992; Bhattacharjee, 2006).

Integrated Pest Management (IPM) and Integrated Disease Management (IDM)

1. Introduction

Cut flower crops are highly sensitive to pests and diseases, as even minor damage reduces aesthetic value, marketability, and export quality. Excessive reliance on chemicals leads to resistance, residue problems, and environmental hazards. Therefore, Integrated Pest Management (IPM) and Integrated Disease Management (IDM) are recommended approaches (Bose et al., 1999; Chadha, 1995; Reddy et al., 2007).

2. Integrated Pest Management (IPM)

2.1 Definition

Integrated Pest Management is an eco-friendly approach that combines cultural, mechanical, biological, and chemical methods to keep pest populations below the economic threshold level (ETL).

2.2 Major Insect Pests of Cut Flowers

Pest	Crop Affected	Damage
Aphids	Rose, Chrysanthemum	Sap sucking, distortion
Thrips	Rose, Gerbera	Flower discoloration, scarring
Spider mites	Rose, Carnation	Yellowing, leaf drop
Whiteflies	Gerbera, Chrysanthemum	Honeydew, sooty mould

2.3 Components of IPM

• a) Cultural Control: Use of healthy and pest-free planting material. Crop rotation and field sanitation. Removal of infested plant parts. Balanced fertilization (avoid excess nitrogen).
• b) Mechanical and Physical Control: Hand removal of insects. Yellow and blue sticky traps (aphids, thrips). Insect-proof nets in protected cultivation.
• c) Biological Control: Chrysoperla carnea against aphids. Phytoseiulus persimilis against mites. Beauveria bassiana and Verticillium lecanii.
• d) Chemical Control: Used only when pest population exceeds ETL. Use selective insecticides. Rotate chemicals to prevent resistance.

3. Integrated Disease Management (IDM)

3.1 Definition

Integrated Disease Management involves the combined use of preventive, cultural, biological, and chemical measures to reduce disease incidence and severity.

3.2 Major Diseases of Cut Flowers

Disease	Causal Organism	Crop
Powdery mildew	Oidium spp.	Rose, Gerbera
Botrytis blight	Botrytis cinerea	Rose, Carnation
Fusarium wilt	Fusarium oxysporum	Carnation, Gladiolus
Root rot	Pythium, Rhizoctonia	Gerbera, Rose

3.3 Components of IDM

• a) Cultural Practices: Use of disease-free planting material. Proper spacing and ventilation. Avoid waterlogging. Crop rotation and sanitation.
• b) Biological Control: Trichoderma harzianum against soil-borne pathogens. Pseudomonas fluorescens for root disease suppression.
• c) Chemical Control: Seed, bulb, or soil treatment with fungicides. Need-based fungicide sprays. Rotation of fungicides to avoid resistance.

4. IPM and IDM in Protected Cultivation

• Strict sanitation and hygiene
• Environmental control to reduce disease pressure
• Regular monitoring and scouting
• Minimum pesticide residue for export quality

5. Conclusion

IPM and IDM are essential components of sustainable cut flower production. integrated approaches ensure healthy crops, reduced chemical dependence, environmental safety, and high-quality flowers suitable for domestic and export markets. (Bhattacharjee (2006) and Reddy et al. (2007))

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Production of Cut Flowers for Exhibition Purposes

1. Introduction

Production of flowers for exhibition purposes differs significantly from commercial cut flower production. The objective is not quantity but perfection in form, size, colour, uniformity, and presentation. Exhibition flowers are grown to compete in flower shows, agricultural fairs, and horticultural exhibitions (Arora, 2006; Bose et al., 1999; Randhawa & Mukhopadhyay, 1986).

2. Objectives of Exhibition Flower Production

• Produce flowers with superior size, shape, and colour
• Achieve uniformity and perfection
• Enhance aesthetic appeal for judging standards
• Win awards and recognition

3. Selection of Crop and Variety

• Only elite and true-to-type varieties are selected
• Varieties with large blooms, straight stems, and intense colour preferred
• Common exhibition flowers:
  • Rose
  • Chrysanthemum
  • Carnation
  • Gladiolus
  • Dahlia

4. Cultural Practices for Exhibition Flowers

4.1 Soil and Media Preparation

• Well-drained, fertile soil rich in organic matter
• Thorough soil sterilization
• Soil pH adjusted as per crop requirement

4.2 Planting and Spacing

• Wider spacing to allow better light penetration
• Adequate root zone for vigorous growth

4.3 Nutrient and Water Management

• Balanced fertilization with emphasis on phosphorus and potassium
• Frequent light irrigation to avoid stress
• Avoid excessive nitrogen

5. Special Practices for Exhibition Quality

5.1 Rationing and Disbudding

• Severe rationing to retain only 1–2 buds per plant
• Ensures maximum flower size

5.2 Training and Staking

• Strong staking for straight and erect stems
• Regular adjustment of ties to avoid injury

5.3 Growth Regulator Use

• GA₃ for stem elongation (judicious use)
• Growth retardants to improve form and compactness

5.4 Pest and Disease Control

• Zero tolerance for pest and disease damage
• Preventive sprays preferred

6. Harvesting for Exhibition

• Harvest at peak bloom or as per exhibition rules
• Cut during early morning or evening
• Immediate hydration in clean water

7. Handling, Transport and Presentation

• Use of clean containers and soft packing material
• Protect blooms from mechanical damage
• Proper labeling and staging as per exhibition guidelines

8. Judging Criteria (General)

• Size and form of flower
• Colour intensity and uniformity
• Stem length and strength
• Freedom from pests, diseases, and defects
• Overall presentation

9. Conclusion

Exhibition flower production represents the highest level of floricultural skill. Meticulous cultural practices, precise regulation of growth, and careful handling are essential to produce award-winning, exhibition-quality flowers (Arora, 2006; Bose et al., 1999).

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