Plant hormone - Revision history

Prab: CSV import

2025-02-21T14:19:04Z

CSV import

← Older revision		Revision as of 14:19, 21 February 2025
Line 1:		Line 1:
	~~{{Short description\|Overview of plant hormones and their functions}}~~		= Plant Hormone =

	~~==Overview==~~		[[File:Auxin.jpg\|thumb\|right\|Auxin, a key plant hormone.]]
	[[~~Plant hormones]]~~, ~~also known as [[phytohormones~~]], are naturally occurring organic compounds that play crucial roles in regulating the growth, development, and responses of plants to environmental stimuli. These hormones are produced in low concentrations and can have profound effects on plant physiology, influencing processes such as cell division, elongation, flowering, fruit development, and senescence.

	~~==Types of Plant Hormones==~~		'''Plant hormones''', also known as '''phytohormones''', are naturally occurring organic compounds that play crucial roles in regulating the growth, development, and responses of plants. These hormones are produced in small quantities and can have significant effects on plant physiology.
	Plant hormones are ~~classified into several major groups~~, ~~each with distinct functions~~ and ~~mechanisms~~ of ~~action:~~

	==~~=Auxins=~~==		== Types of Plant Hormones ==
	[[Auxins]] are a class of plant hormones that primarily regulate cell elongation, apical dominance, and root initiation. They are synthesized in the shoot apical meristem and young leaves and are transported downwards through the plant. Auxins play a key role in phototropism and gravitropism, allowing plants to grow towards light and against gravity.

	~~===Cytokinins===~~		Plant hormones are classified into several major groups, each with distinct functions and effects on plant growth and development.
	~~[[Cytokinins]]~~ are ~~involved in promoting cell division and differentiation~~, ~~particularly in the roots~~ and ~~shoots. They work in conjunction with auxins to regulate~~ growth and development~~, influencing processes such as leaf senescence and nutrient mobilization. Cytokinins are synthesized in the roots and transported to other parts of the plant~~.

	===~~Gibberellins~~===		=== Auxins ===
	[[~~Gibberellins~~]] are a ~~group~~ of hormones that ~~stimulate stem~~ elongation, ~~seed germination~~, and ~~flowering~~. ~~They~~ are ~~essential for breaking seed dormancy and promoting the growth of young seedlings. Gibberellins also play a role~~ in ~~fruit development and can influence the size~~ and ~~shape of fruits~~.		[[File:Indol-3-ylacetic_acid.svg\|thumb\|left\|Chemical structure of Indole-3-acetic acid, a common auxin.]]
			Auxins are a class of plant hormones that primarily regulate cell elongation, apical dominance, and root initiation. The most common naturally occurring auxin is [[Indole-3-acetic acid]] (IAA). Auxins are involved in various plant processes, including phototropism and gravitropism.

	===~~Ethylene~~===		=== Cytokinins ===
	[[~~Ethylene~~]] is a ~~gaseous hormone~~ that ~~regulates fruit ripening, leaf abscission,~~ and ~~response to stress~~. ~~It is produced~~ in ~~response to environmental cues~~ such as ~~wounding~~, ~~drought~~, and ~~flooding~~. ~~Ethylene~~ is ~~unique among plant hormones due to its gaseous nature, allowing it to diffuse easily through plant tissues~~.		[[File:Zeatin.png\|thumb\|right\|Chemical structure of Zeatin, a type of cytokinin.]]
			Cytokinins are a group of hormones that promote cell division and differentiation. They are involved in processes such as shoot initiation and growth, leaf expansion, and delay of senescence. Zeatin is a well-known cytokinin found in many plants.

	===~~Abscisic Acid~~===		=== Gibberellins ===
	[[~~Abscisic acid~~]] ~~(ABA) is primarily involved in stress responses and the regulation~~ of ~~stomatal closure. It plays a critical role in helping plants cope with drought~~ and ~~other environmental stresses by reducing water loss through transpiration~~. ~~ABA also influences~~ seed dormancy and ~~germination~~.		[[File:Gibberellin_A1.svg\|thumb\|left\|Chemical structure of Gibberellin A1.]]
			Gibberellins are a group of hormones that stimulate stem elongation, seed germination, and flowering. They are essential for breaking seed dormancy and promoting growth in various plant parts. Gibberellin A1 is one of the many gibberellins identified in plants.

	===~~Brassinosteroids~~===		=== Abscisic Acid ===
	[[~~Brassinosteroids~~]] ~~are~~ a ~~class of polyhydroxysteroids~~ that ~~promote cell expansion and elongation~~, ~~vascular differentiation~~, and ~~reproductive development~~. ~~They are essential for normal plant growth and development~~ and ~~help plants respond to various environmental stresses~~.		[[File:Abscisic_acid.svg\|thumb\|right\|Chemical structure of Abscisic acid.]]
			Abscisic acid (ABA) is a plant hormone that plays a crucial role in stress responses, such as drought tolerance, and in the regulation of stomatal closure. It is also involved in seed dormancy and abscission processes.

	===~~Jasmonates~~===		=== Ethylene ===
	[[~~Jasmonates~~]] ~~are involved in~~ plant ~~defense responses~~ and ~~the regulation of growth~~ and ~~development. They play a key role~~ in the ~~plant's~~ response to ~~herbivory~~ and pathogen attack~~, as well as in the regulation of reproductive processes~~.		[[File:Ethene-2D-flat.png\|thumb\|left\|Chemical structure of Ethylene.]]
			Ethylene is a gaseous plant hormone that influences fruit ripening, flower wilting, and leaf abscission. It is unique among plant hormones due to its gaseous state and is involved in the response to mechanical stress and pathogen attack.

	===~~Salicylic Acid~~===		=== Brassinosteroids ===
	[[~~Salicylic acid~~]] is a ~~phenolic compound~~ that ~~plays a crucial role in plant defense mechanisms~~, ~~particularly in systemic acquired resistance (SAR) against pathogens~~. It is ~~also involved in~~ the ~~regulation~~ of ~~flowering and thermogenesis.~~		[[File:Brassinolide.png\|thumb\|right\|Chemical structure of Brassinolide, a type of brassinosteroid.]]
			Brassinosteroids are a class of polyhydroxysteroids that promote cell expansion and elongation, vascular differentiation, and stress tolerance. Brassinolide is one of the most studied brassinosteroids.

			== Functions of Plant Hormones ==

	~~==Functions of Plant Hormones==~~
	Plant hormones regulate a wide range of physiological processes, including:		Plant hormones regulate a wide range of physiological processes, including:

	* '''Growth and Development''': Hormones like auxins, cytokinins, and gibberellins ~~coordinate~~ cell division, elongation, and differentiation~~, influencing overall plant architecture~~.		* '''Growth and Development''': Hormones like auxins, cytokinins, and gibberellins are crucial for cell division, elongation, and differentiation.
	* '''Stress Responses''': Abscisic acid and ethylene ~~help plants respond~~ to ~~abiotic~~ stresses such as drought, salinity, and ~~temperature extremes~~.		* '''Stress Responses''': Abscisic acid and ethylene play significant roles in plant responses to environmental stresses such as drought, salinity, and pathogen attack.
	* '''Reproductive Development''': ~~Gibberellins and brassinosteroids are involved in~~ flowering ~~and~~ fruit development, ~~while jasmonates~~ and ~~salicylic acid play roles in defense during reproduction~~.		* '''Reproductive Development''': Hormones regulate flowering, fruit development, and seed germination.
	* '''Senescence and Abscission''': Ethylene and ~~cytokinins regulate~~ leaf senescence and abscission~~, allowing plants to shed old or damaged tissues~~.		* '''Senescence and Abscission''': Ethylene and abscisic acid are involved in leaf senescence and the abscission of leaves and fruits.

	~~==Images==~~		== Related Pages ==
	~~[[File:Auxin transport.png\|thumb\|right\|Diagram showing auxin transport in plant tissues.]]~~		* [[Phototropism]]
			* [[Gravitropism]]
	~~[[File:Ethylene production.png\|thumb\|left\|Ethylene production in response to stress factors.]]~~		* [[Seed dormancy]]
			* [[Apical dominance]]
	==Related Pages==
	* [[~~Plant physiology~~]]
	* [[~~Photosynthesis~~]]
	* [[~~Plant anatomy~~]]
	* [[~~Botany~~]]

			[[Category:Plant physiology]]
	[[Category:Plant hormones]]		[[Category:Plant hormones]]
	~~[[Category:Plant physiology]]~~

Prab: CSV import

2025-02-18T17:45:17Z

CSV import

← Older revision		Revision as of 17:45, 18 February 2025
Line 1:		Line 1:
	'''Plant hormones''' (also known as '''phytohormones''') are chemicals that regulate plant growth. In the UK, these are termed 'plant growth substances'. Plant hormones are signal molecules produced within the plant, and occur in extremely low concentrations. Hormones regulate cellular processes in targeted cells locally and, when moved to other locations, in other locations of ~~the~~ plant. Hormones also determine the formation of flowers, stems, leaves, the shedding of leaves, and the development and ripening of fruit. Plants, unlike animals, lack glands that produce and secrete hormones. Instead, each cell is capable of producing hormones. Plant hormones ~~shape the plant, affecting seed growth, time of flowering, the sex of flowers, senescence of leaves, and fruits. They affect which tissues grow upward and which grow downward, leaf formation~~ and stem growth, fruit development and ripening, plant longevity, and even plant death. Hormones are vital to plant growth, and, lacking them, plants would be mostly a mass of undifferentiated cells. So they are also known as growth factors or growth hormones.		{{Short description\|Overview of plant hormones and their functions}}

	~~The term '''phytohormone''' was coined by Thimann~~ in ~~1948. The word 'phytohormone' is derived from Greek φυτόν ('phyton')~~, ~~meaning 'plant'~~ and ~~hormone, meaning '~~to ~~set~~ in ~~motion'~~.		==Overview==
			[[Plant hormones]], also known as [[phytohormones]], are naturally occurring organic compounds that play crucial roles in regulating the growth, development, and responses of plants to environmental stimuli. These hormones are produced in low concentrations and can have profound effects on plant physiology, influencing processes such as cell division, elongation, flowering, fruit development, and senescence.

	==Types of ~~plant hormones~~==		==Types of Plant Hormones==
	Plant hormones are ~~categorized~~ into ~~five main types: [[auxin]]~~, ~~[[cytokinin]], [[gibberellin]], [[abscisic acid]]~~ and ~~[[ethylene]]. Each~~ of ~~these hormones has a distinct role in plant growth and development.~~		Plant hormones are classified into several major groups, each with distinct functions and mechanisms of action:

	===~~Auxin~~===		===Auxins===
	[[~~Auxin~~]] is a plant ~~hormone produced in the stem tip~~ that ~~promotes~~ cell elongation. ~~Auxin moves to~~ the ~~darker side of~~ the plant, ~~causing the cells there~~ to grow ~~larger than corresponding cells on the lighter side of the plant~~.		[[Auxins]] are a class of plant hormones that primarily regulate cell elongation, apical dominance, and root initiation. They are synthesized in the shoot apical meristem and young leaves and are transported downwards through the plant. Auxins play a key role in phototropism and gravitropism, allowing plants to grow towards light and against gravity.

	===~~Cytokinin~~===		===Cytokinins===
	[[~~Cytokinin~~]]s are ~~a class of plant growth substances that promote~~ cell division, ~~or cytokinesis,~~ in ~~plant~~ roots and shoots. They are ~~involved primarily~~ in ~~cell growth~~ and ~~differentiation~~.		[[Cytokinins]] are involved in promoting cell division and differentiation, particularly in the roots and shoots. They work in conjunction with auxins to regulate growth and development, influencing processes such as leaf senescence and nutrient mobilization. Cytokinins are synthesized in the roots and transported to other parts of the plant.

	===~~Gibberellin~~===		===Gibberellins===
	[[~~Gibberellin~~]]s are ~~plant~~ hormones that ~~regulate growth and influence various developmental processes, including~~ stem elongation, germination, dormancy, ~~flowering~~, ~~sex expression~~, ~~enzyme induction~~, and ~~leaf and fruit senescence~~.		[[Gibberellins]] are a group of hormones that stimulate stem elongation, seed germination, and flowering. They are essential for breaking seed dormancy and promoting the growth of young seedlings. Gibberellins also play a role in fruit development and can influence the size and shape of fruits.

			===Ethylene===
			[[Ethylene]] is a gaseous hormone that regulates fruit ripening, leaf abscission, and response to stress. It is produced in response to environmental cues such as wounding, drought, and flooding. Ethylene is unique among plant hormones due to its gaseous nature, allowing it to diffuse easily through plant tissues.

	===Abscisic Acid===		===Abscisic Acid===
	[[Abscisic acid]] (ABA) is a plant ~~hormone~~. ~~ABA functions~~ in ~~many~~ plant ~~developmental processes, including seed~~ and ~~bud dormancy~~, the ~~control~~ of ~~organ size~~, and ~~stomatal closure~~.		[[Abscisic acid]] (ABA) is primarily involved in stress responses and the regulation of stomatal closure. It plays a critical role in helping plants cope with drought and other environmental stresses by reducing water loss through transpiration. ABA also influences seed dormancy and germination.

			===Brassinosteroids===
			[[Brassinosteroids]] are a class of polyhydroxysteroids that promote cell expansion and elongation, vascular differentiation, and reproductive development. They are essential for normal plant growth and development and help plants respond to various environmental stresses.

			===Jasmonates===
			[[Jasmonates]] are involved in plant defense responses and the regulation of growth and development. They play a key role in the plant's response to herbivory and pathogen attack, as well as in the regulation of reproductive processes.

			===Salicylic Acid===
			[[Salicylic acid]] is a phenolic compound that plays a crucial role in plant defense mechanisms, particularly in systemic acquired resistance (SAR) against pathogens. It is also involved in the regulation of flowering and thermogenesis.

			==Functions of Plant Hormones==
			Plant hormones regulate a wide range of physiological processes, including:

	==~~=Ethylene=~~==		* '''Growth and Development''': Hormones like auxins, cytokinins, and gibberellins coordinate cell division, elongation, and differentiation, influencing overall plant architecture.
	[[~~Ethylene~~]] ~~is a gaseous plant hormone which regulates a wide range of biological processes~~. ~~It is involved~~ in ~~processes such as ripening of fruits, opening of flowers, shedding of leaves, and senescence of green tissues~~.		* '''Stress Responses''': Abscisic acid and ethylene help plants respond to abiotic stresses such as drought, salinity, and temperature extremes.
			* '''Reproductive Development''': Gibberellins and brassinosteroids are involved in flowering and fruit development, while jasmonates and salicylic acid play roles in defense during reproduction.
			* '''Senescence and Abscission''': Ethylene and cytokinins regulate leaf senescence and abscission, allowing plants to shed old or damaged tissues.

			==Images==
			[[File:Auxin transport.png\|thumb\|right\|Diagram showing auxin transport in plant tissues.]]

			[[File:Ethylene production.png\|thumb\|left\|Ethylene production in response to stress factors.]]

	==~~See also~~==		==Related Pages==
	* [[Plant physiology]]		* [[Plant physiology]]
	* [[~~Plant perception (physiology)~~]]		* [[Photosynthesis]]
	* [[Plant ~~morphology~~]]		* [[Plant anatomy]]
			* [[Botany]]
	~~==References==~~
	~~<references />~~

	[[Category:Plant hormones]]		[[Category:Plant hormones]]
	[[Category:Plant physiology]]		[[Category:Plant physiology]]
	~~[[Category:Botany]]~~
	~~{{stub}}~~
	~~<gallery>~~
	~~File:Auxin.jpg\|Auxin~~
	~~File:Phyllody_on_Coneflower_with_aster_yellows.jpg\|Phyllody on Coneflower with aster yellows~~
	~~File:Abscisic_acid.svg\|Abscisic acid~~
	~~File:Indol-3-ylacetic_acid.svg\|Indol-3-ylacetic acid~~
	~~File:Brassinolide.png\|Brassinolide~~
	~~File:Zeatin.png\|Zeatin~~
	~~File:Ethene-2D-flat.png\|Ethene~~
	~~File:Gibberellin_A1.svg\|Gibberellin A1~~
	~~File:Jasmonic_acid.svg\|Jasmonic acid~~
	~~File:2-hydroxybenzoic_acid_200.svg\|2-hydroxybenzoic acid~~
	~~File:5-Deoxystrigol_chemical_structure.png\|5-Deoxystrigol~~
	~~</gallery>~~

Prab: CSV import

2025-02-18T12:06:26Z

CSV import

← Older revision		Revision as of 12:06, 18 February 2025
Line 33:		Line 33:
	[[Category:Botany]]		[[Category:Botany]]
	{{stub}}		{{stub}}
			<gallery>
			File:Auxin.jpg\|Auxin
			File:Phyllody_on_Coneflower_with_aster_yellows.jpg\|Phyllody on Coneflower with aster yellows
			File:Abscisic_acid.svg\|Abscisic acid
			File:Indol-3-ylacetic_acid.svg\|Indol-3-ylacetic acid
			File:Brassinolide.png\|Brassinolide
			File:Zeatin.png\|Zeatin
			File:Ethene-2D-flat.png\|Ethene
			File:Gibberellin_A1.svg\|Gibberellin A1
			File:Jasmonic_acid.svg\|Jasmonic acid
			File:2-hydroxybenzoic_acid_200.svg\|2-hydroxybenzoic acid
			File:5-Deoxystrigol_chemical_structure.png\|5-Deoxystrigol
			</gallery>

Prab: CSV import

2024-02-25T18:39:58Z

CSV import

New page

'''Plant hormones''' (also known as '''phytohormones''') are chemicals that regulate plant growth. In the UK, these are termed 'plant growth substances'. Plant hormones are signal molecules produced within the plant, and occur in extremely low concentrations. Hormones regulate cellular processes in targeted cells locally and, when moved to other locations, in other locations of the plant. Hormones also determine the formation of flowers, stems, leaves, the shedding of leaves, and the development and ripening of fruit. Plants, unlike animals, lack glands that produce and secrete hormones. Instead, each cell is capable of producing hormones. Plant hormones shape the plant, affecting seed growth, time of flowering, the sex of flowers, senescence of leaves, and fruits. They affect which tissues grow upward and which grow downward, leaf formation and stem growth, fruit development and ripening, plant longevity, and even plant death. Hormones are vital to plant growth, and, lacking them, plants would be mostly a mass of undifferentiated cells. So they are also known as growth factors or growth hormones.

The term '''phytohormone''' was coined by Thimann in 1948. The word 'phytohormone' is derived from Greek φυτόν ('phyton'), meaning 'plant' and hormone, meaning 'to set in motion'.

==Types of plant hormones==
Plant hormones are categorized into five main types: [[auxin]], [[cytokinin]], [[gibberellin]], [[abscisic acid]] and [[ethylene]]. Each of these hormones has a distinct role in plant growth and development.

===Auxin===
[[Auxin]] is a plant hormone produced in the stem tip that promotes cell elongation. Auxin moves to the darker side of the plant, causing the cells there to grow larger than corresponding cells on the lighter side of the plant.

===Cytokinin===
[[Cytokinin]]s are a class of plant growth substances that promote cell division, or cytokinesis, in plant roots and shoots. They are involved primarily in cell growth and differentiation.

===Gibberellin===
[[Gibberellin]]s are plant hormones that regulate growth and influence various developmental processes, including stem elongation, germination, dormancy, flowering, sex expression, enzyme induction, and leaf and fruit senescence.

===Abscisic Acid===
[[Abscisic acid]] (ABA) is a plant hormone. ABA functions in many plant developmental processes, including seed and bud dormancy, the control of organ size, and stomatal closure.

===Ethylene===
[[Ethylene]] is a gaseous plant hormone which regulates a wide range of biological processes. It is involved in processes such as ripening of fruits, opening of flowers, shedding of leaves, and senescence of green tissues.

==See also==
* [[Plant physiology]]
* [[Plant perception (physiology)]]
* [[Plant morphology]]

==References==
<references />

[[Category:Plant hormones]]
[[Category:Plant physiology]]
[[Category:Botany]]
{{stub}}

← Older revision		Revision as of 12:06, 18 February 2025
Line 33:		Line 33:
	[[Category:Botany]]		[[Category:Botany]]
	{{stub}}		{{stub}}
			<gallery>
			File:Auxin.jpg\|Auxin
			File:Phyllody_on_Coneflower_with_aster_yellows.jpg\|Phyllody on Coneflower with aster yellows
			File:Abscisic_acid.svg\|Abscisic acid
			File:Indol-3-ylacetic_acid.svg\|Indol-3-ylacetic acid
			File:Brassinolide.png\|Brassinolide
			File:Zeatin.png\|Zeatin
			File:Ethene-2D-flat.png\|Ethene
			File:Gibberellin_A1.svg\|Gibberellin A1
			File:Jasmonic_acid.svg\|Jasmonic acid
			File:2-hydroxybenzoic_acid_200.svg\|2-hydroxybenzoic acid
			File:5-Deoxystrigol_chemical_structure.png\|5-Deoxystrigol
			</gallery>