History and Classification of Growth Regulators
NAME: Muhammad Shafiq�DATE: MAR 2025
PRESENTATION TITLE
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Agenda
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Introduction to PGRs
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Historical Development
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Classification of PGRs
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Synthesized Hormones
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Natural Regulators
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Effects on Plant Growth
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Applications of PGRs
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Future Trends
History and Classification of Growth Regulators
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Introduction to PGRs
Defining Plant Growth Regulators
Plant Growth Regulators (PGRs) are chemicals that influence plant growth, development, and response to environmental stimuli. They play a crucial role in agriculture, improving yield and quality.
History and Classification of Growth Regulators
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Historical Development
Discovery of Auxins
The first plant hormones, auxins, were discovered, significantly influencing plant development.
1930s
Synthetic PGRs
First synthetic growth regulators were developed, leading to advancements in agricultural practices.
1950s
Global Application
PGRs became widely used in farming, contributing to enhanced crop yields worldwide.
1980s
Biotechnology Integration
Integration of biotechnology led to the development of more effective PGRs.
2000s
Sustainability Focus
Research increasingly focuses on sustainable PGRs to meet global food demands.
2020s
History and Classification of Growth Regulators
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Classification of PGRs
Major Categories
PGRs are classified into five major categories: auxins, gibberellins, cytokinins, ethylene, and abscisic acid, each having distinct roles in plant growth.
Applications
Each category of PGRs has specific applications, such as regulating fruit ripening, promoting stem elongation, and enhancing flowering.
History and Classification of Growth Regulators
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TYPE | EXAMPLE | APPLICATION |
Auxins | IAA | Stimulates root growth |
Gibberellins | GA3 | Promotes fruit size |
Cytokinins | Zeatin | Encourages cell division |
Ethylene | Ethrel | Used in fruit ripening |
Abscisic Acid | ABA | Inhibits growth under stress |
Synthesized Hormones
This table compares different synthesized hormones, showcasing their types, examples, and applications, highlighting their unique roles in plant development.
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TYPE | SOURCE | FUNCTION |
Auxins | Plant tissues | Cell elongation and differentiation |
Cytokinins | Coconut milk | Promotes cell division |
Gibberellins | Fungal sources | Stem growth and seed germination |
Ethylene | Ripening fruits | Regulates fruit ripening |
Abscisic Acid | Chloroplasts | Stress response regulation |
Natural Regulators
This table details natural growth regulators, their sources, and their functions in plants, providing insight into how nature influences plant growth.
Effects on Plant Growth
Influence on Growth and Development
PGRs significantly affect various aspects of plant growth, including germination, flowering, fruit development, and responses to stress. Their manipulation can lead to higher productivity.
History and Classification of Growth Regulators
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Applications of PGRs
In Agriculture
PGRs are used to enhance crop yields, control flowering times, and improve the quality of fruits and vegetables.
In Horticulture
Used to manage plant growth, regulate blooming, and maintain plant structure in ornamental plants.
Research and Development
Ongoing research focuses on more efficient and sustainable PGRs to meet changing agricultural demands.
History and Classification of Growth Regulators
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Future Trends
Innovations and Sustainability
Future developments in PGR research aim at sustainable practices, including the use of natural regulators and biotechnological advancements to increase efficiency and reduce environmental impact.
History and Classification of Growth Regulators
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