The Role of Silicon in Antiherbivore Phytohormonal Signalling

The role of plant silicon (Si) in the alleviation of abiotic and biotic stress is now widely recognised and researched. Amongst the biotic stresses, Si is known to increase resistance to herbivores through biomechanical and chemical mechanisms, although the latter are indirect and remain poorly char...

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Main Authors: Casey R. Hall, Jamie M. Waterman, Rebecca K. Vandegeer, Susan E. Hartley, Scott N. Johnson
Format: Article
Language:English
Published: Frontiers Media S.A. 2019-09-01
Series:Frontiers in Plant Science
Subjects:
Online Access:https://www.frontiersin.org/article/10.3389/fpls.2019.01132/full
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author Casey R. Hall
Jamie M. Waterman
Rebecca K. Vandegeer
Susan E. Hartley
Scott N. Johnson
author_facet Casey R. Hall
Jamie M. Waterman
Rebecca K. Vandegeer
Susan E. Hartley
Scott N. Johnson
author_sort Casey R. Hall
collection DOAJ
description The role of plant silicon (Si) in the alleviation of abiotic and biotic stress is now widely recognised and researched. Amongst the biotic stresses, Si is known to increase resistance to herbivores through biomechanical and chemical mechanisms, although the latter are indirect and remain poorly characterised. Chemical defences are principally regulated by several antiherbivore phytohormones. The jasmonic acid (JA) signalling pathway is particularly important and has been linked to Si supplementation, albeit with some contradictory findings. In this Perspectives article, we summarise existing knowledge of how Si affects JA in the context of herbivory and present a conceptual model for the interactions between Si and JA signalling in wounded plants. Further, we use novel information from the model grass Brachypodium distachyon to underpin aspects of this model. We show that Si reduces JA concentrations in plants subjected to chemical induction (methyl jasmonate) and herbivory (Helicoverpa armigera) by 34% and 32%, respectively. Moreover, +Si plants had 13% more leaf macrohairs than −Si plants. From this study and previous work, our model proposes that Si acts as a physical stimulus in the plant, which causes a small, transient increase in JA. When +Si plants are subsequently attacked by herbivores, they potentially show a faster induction of JA due to this priming. +Si plants that have already invested in biomechanical defences (e.g. macrohairs), however, have less utility for JA-induced defences and show lower levels of JA induction overall.
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spelling doaj.art-39db05e1942e4d9fbbb3f8f21141f91a2022-12-22T02:09:35ZengFrontiers Media S.A.Frontiers in Plant Science1664-462X2019-09-011010.3389/fpls.2019.01132472867The Role of Silicon in Antiherbivore Phytohormonal SignallingCasey R. Hall0Jamie M. Waterman1Rebecca K. Vandegeer2Susan E. Hartley3Scott N. Johnson4Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, AustraliaHawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, AustraliaHawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, AustraliaYork Environment and Sustainability Institute, Department of Biology, University of York, York, United KingdomHawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, AustraliaThe role of plant silicon (Si) in the alleviation of abiotic and biotic stress is now widely recognised and researched. Amongst the biotic stresses, Si is known to increase resistance to herbivores through biomechanical and chemical mechanisms, although the latter are indirect and remain poorly characterised. Chemical defences are principally regulated by several antiherbivore phytohormones. The jasmonic acid (JA) signalling pathway is particularly important and has been linked to Si supplementation, albeit with some contradictory findings. In this Perspectives article, we summarise existing knowledge of how Si affects JA in the context of herbivory and present a conceptual model for the interactions between Si and JA signalling in wounded plants. Further, we use novel information from the model grass Brachypodium distachyon to underpin aspects of this model. We show that Si reduces JA concentrations in plants subjected to chemical induction (methyl jasmonate) and herbivory (Helicoverpa armigera) by 34% and 32%, respectively. Moreover, +Si plants had 13% more leaf macrohairs than −Si plants. From this study and previous work, our model proposes that Si acts as a physical stimulus in the plant, which causes a small, transient increase in JA. When +Si plants are subsequently attacked by herbivores, they potentially show a faster induction of JA due to this priming. +Si plants that have already invested in biomechanical defences (e.g. macrohairs), however, have less utility for JA-induced defences and show lower levels of JA induction overall.https://www.frontiersin.org/article/10.3389/fpls.2019.01132/fullallelochemicalinduced defencesinsectjasmonatesplant defencesilica
spellingShingle Casey R. Hall
Jamie M. Waterman
Rebecca K. Vandegeer
Susan E. Hartley
Scott N. Johnson
The Role of Silicon in Antiherbivore Phytohormonal Signalling
Frontiers in Plant Science
allelochemical
induced defences
insect
jasmonates
plant defence
silica
title The Role of Silicon in Antiherbivore Phytohormonal Signalling
title_full The Role of Silicon in Antiherbivore Phytohormonal Signalling
title_fullStr The Role of Silicon in Antiherbivore Phytohormonal Signalling
title_full_unstemmed The Role of Silicon in Antiherbivore Phytohormonal Signalling
title_short The Role of Silicon in Antiherbivore Phytohormonal Signalling
title_sort role of silicon in antiherbivore phytohormonal signalling
topic allelochemical
induced defences
insect
jasmonates
plant defence
silica
url https://www.frontiersin.org/article/10.3389/fpls.2019.01132/full
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