Reversal of etiolation

Etiolated plants are those that have been grown in the dark, light stimulates increased [cytokinin] which stimulates cell division and greening.

increases [GA] which presumably stimulates IAA oxidase production to get rid of excess IAA that causes the long spindly growth.

IAA stimulates ethylene synthesis which maintains the apical hook, treating the apical hook with red light + ethylene maintains the hook.

TLS Online TPP Program

#Id: 9760

#Unit 6. System Physiology – Plant

Many plants release a specific bouquet of volatile organic compounds when attacked by insect herbivores. These volatiles can consist of compounds from all major pathways for secondary metabolites including terpenoids (mono- and sesquiterpenes), alkaloids (indole), and phenylpropanes (methyl salicylate), as well as green-leaf volatiles. 

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#Id: 9761

#Unit 6. System Physiology – Plant

These VOCs are herbivore– induced plant volatiles (HIPV) HIPV and act as cues for natural enemies of the insect herbivore, for example parasitic wasps.

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#Id: 9762

#Unit 6. System Physiology – Plant

When maize plants were exposed to green-leaf volatiles (VOCs), JA and JA-related gene expression were rapidly induced.

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#Id: 9763

#Unit 6. System Physiology – Plant

To distinguish between “self” and “nonself” during pathogen infection, plants possess pattern recognition receptors (PRRs) that perceive microbe-associated molecular patterns (MAMPs) which are conserved among a specific class of microorganisms (such as chitin for fungi, flagella for bacteria) but are absent in the host.

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#Id: 9764

#Unit 6. System Physiology – Plant

Perception of MAMPs or DAMPs by cell surface PRRs is called Pathogen Triggered Immunity

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#Id: 9765

#Unit 6. System Physiology – Plant

Perception of MAMPs or DAMPs by cell surface PRRs initiates a localized basal defense response called MAMP triggered immunity which inhibits the growth and activity of nonadapted pathogens or pests.