Green leaf volatiles: Difference between revisions

Revision as of 06:02, 16 February 2025

Green Leaf Volatiles

Green leaf volatiles are emitted by plants when damaged.

Green leaf volatiles (GLVs) are a group of volatile organic compounds that are released by plants when they experience mechanical damage, such as herbivore attack or physical injury. These compounds play a crucial role in plant defense mechanisms and inter-plant communication.

Chemical Composition

GLVs are primarily composed of six-carbon aldehydes, alcohols, and esters. The most common GLVs include hexanal, hexenol, and hexenyl acetate. These compounds are derived from the lipoxygenase pathway, which involves the enzymatic oxidation of fatty acids.

Biosynthesis

The biosynthesis of GLVs begins with the action of lipoxygenase on linolenic acid, a fatty acid found in plant membranes. This reaction produces hydroperoxides, which are then cleaved by hydroperoxide lyase to form C6 aldehydes. These aldehydes can be further reduced to alcohols or esterified to form esters.

Ecological Role

GLVs serve multiple ecological functions. They act as signals to attract natural enemies of herbivores, such as predators and parasitoids, thereby providing an indirect defense mechanism for the plant. Additionally, GLVs can signal neighboring plants to activate their own defense responses, a phenomenon known as "priming".

Human Perception and Uses

Humans perceive GLVs as the "green" smell associated with freshly cut grass or crushed leaves. This characteristic aroma is utilized in the flavor and fragrance industries to create products with a fresh, green scent.

Related Pages

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-'''Green Leaf Volatiles (GLVs)''' are a group of [[volatile organic compounds]] (VOCs) that are released by plants when they are damaged or stressed. These compounds are responsible for the characteristic "green" odor associated with freshly cut grass or damaged leaves. GLVs play a significant role in plant biology, including serving as signals for plant-to-plant communication and in the attraction of predatory insects that feed on herbivores attacking the plants.
+== Green Leaf Volatiles ==
-==Production and Composition==
+[[File:Green_leaf_volatiles.jpg|thumb|right|Green leaf volatiles are emitted by plants when damaged.]]
-GLVs are produced through the [[lipid peroxidation]] of polyunsaturated fatty acids. This process is initiated by the action of enzymes such as [[lipoxygenase]] (LOX) following physical damage to plant tissues. The primary components of GLVs include six-carbon aldehydes, alcohols, and their esters, such as hexanal, (Z)-3-hexenal, (E)-2-hexenal, hexanol, and (Z)-3-hexenol. Among these, (Z)-3-hexenal is particularly notable for its potent green odor.
-==Biological Functions==
+'''Green leaf volatiles''' (GLVs) are a group of volatile organic compounds that are released by plants when they experience mechanical damage, such as herbivore attack or physical injury. These compounds play a crucial role in plant defense mechanisms and inter-plant communication.
-GLVs have several important biological functions:
-===Defense Mechanism===
+== Chemical Composition ==
-GLVs can act as direct defense mechanisms against herbivores by deterring their feeding. Some GLVs are toxic or repellant to certain insects, reducing the likelihood of further damage to the plant.
-===Signaling===
+GLVs are primarily composed of six-carbon aldehydes, alcohols, and esters. The most common GLVs include [[hexanal]], [[hexenol]], and [[hexenyl acetate]]. These compounds are derived from the [[lipoxygenase]] pathway, which involves the enzymatic oxidation of fatty acids.
-GLVs also serve as indirect defense mechanisms by signaling the presence of herbivores to predatory insects and mites, which then prey upon the herbivores. This signaling can occur both within a single plant and between plants, alerting neighboring plants to the threat and triggering their own defensive responses.
-===Stress Response===
+== Biosynthesis ==
-The release of GLVs is part of the plant's stress response mechanism. Apart from herbivore attack, GLVs can be released in response to other stress factors such as mechanical damage, pathogen infection, and abiotic stresses.
-==Ecological Impact==
+[[File:LyaseNonenalHemiAc.png|thumb|left|Enzymatic pathways involved in the biosynthesis of GLVs.]]
-GLVs play a significant role in the ecosystem by mediating interactions between plants and insects, including pollinators and herbivores, as well as between plants themselves. They contribute to the complexity of plant communities and biodiversity by influencing plant competition, herbivory, and predation patterns.
-==Research and Applications==
+The biosynthesis of GLVs begins with the action of [[lipoxygenase]] on linolenic acid, a fatty acid found in plant membranes. This reaction produces hydroperoxides, which are then cleaved by hydroperoxide lyase to form C6 aldehydes. These aldehydes can be further reduced to alcohols or esterified to form esters.
-Research on GLVs has implications for agriculture, pest management, and the study of plant ecology and evolution. Understanding the role of GLVs in plant defense can lead to the development of crop protection strategies that exploit natural plant defenses, reducing the need for chemical pesticides.
+== Ecological Role ==
+GLVs serve multiple ecological functions. They act as signals to attract natural enemies of herbivores, such as predators and parasitoids, thereby providing an indirect defense mechanism for the plant. Additionally, GLVs can signal neighboring plants to activate their own defense responses, a phenomenon known as "[[priming]]".
+== Human Perception and Uses ==
+Humans perceive GLVs as the "green" smell associated with freshly cut grass or crushed leaves. This characteristic aroma is utilized in the flavor and fragrance industries to create products with a fresh, green scent.
+== Related Pages ==
+* [[Volatile organic compound]]
+* [[Plant defense against herbivory]]
+* [[Lipoxygenase]]
+* [[Priming (biology)]]
 [[Category:Plant physiology]]
-[[Category:Biochemistry]]
+[[Category:Volatile organic compounds]]
-[[Category:Ecology]]
-{{Biochemistry-stub}}