Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.

Predicted increases in atmospheric carbon dioxide (CO2) are widely anticipated to increase biomass accumulation by accelerating rates of photosynthesis in many plant taxa. Little, however, is known about how soil-borne plant antagonists might modify the effects of elevated CO2 (eCO2), with root-feed...

Full description

Bibliographic Details
Main Authors: Scott N Johnson, Markus Riegler
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2013-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3832529?pdf=render
_version_ 1818897170926927872
author Scott N Johnson
Markus Riegler
author_facet Scott N Johnson
Markus Riegler
author_sort Scott N Johnson
collection DOAJ
description Predicted increases in atmospheric carbon dioxide (CO2) are widely anticipated to increase biomass accumulation by accelerating rates of photosynthesis in many plant taxa. Little, however, is known about how soil-borne plant antagonists might modify the effects of elevated CO2 (eCO2), with root-feeding insects being particularly understudied. Root damage by insects often reduces rates of photosynthesis by disrupting root function and imposing water deficits. These insects therefore have considerable potential for modifying plant responses to eCO2. We investigated how root damage by a soil-dwelling insect (Xylotrupes gideon australicus) modified the responses of Eucalyptus globulus to eCO2. eCO2 increased plant height when E. globulus were 14 weeks old and continued to do so at an accelerated rate compared to those grown at ambient CO2 (aCO2). Plants exposed to root-damaging insects showed a rapid decline in growth rates thereafter. In eCO2, shoot and root biomass increased by 46 and 35%, respectively, in insect-free plants but these effects were arrested when soil-dwelling insects were present so that plants were the same size as those grown at aCO2. Specific leaf mass increased by 29% under eCO2, but at eCO2 root damage caused it to decline by 16%, similar to values seen in plants at aCO2 without root damage. Leaf C:N ratio increased by >30% at eCO2 as a consequence of declining leaf N concentrations, but this change was also moderated by soil insects. Soil insects also reduced leaf water content by 9% at eCO2, which potentially arose through impaired water uptake by the roots. We hypothesise that this may have impaired photosynthetic activity to the extent that observed plant responses to eCO2 no longer occurred. In conclusion, soil-dwelling insects could modify plant responses to eCO2 predicted by climate change plant growth models.
first_indexed 2024-12-19T19:11:56Z
format Article
id doaj.art-48659828875a4d058600980a28b6701d
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-19T19:11:56Z
publishDate 2013-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-48659828875a4d058600980a28b6701d2022-12-21T20:09:15ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-01811e7947910.1371/journal.pone.0079479Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.Scott N JohnsonMarkus RieglerPredicted increases in atmospheric carbon dioxide (CO2) are widely anticipated to increase biomass accumulation by accelerating rates of photosynthesis in many plant taxa. Little, however, is known about how soil-borne plant antagonists might modify the effects of elevated CO2 (eCO2), with root-feeding insects being particularly understudied. Root damage by insects often reduces rates of photosynthesis by disrupting root function and imposing water deficits. These insects therefore have considerable potential for modifying plant responses to eCO2. We investigated how root damage by a soil-dwelling insect (Xylotrupes gideon australicus) modified the responses of Eucalyptus globulus to eCO2. eCO2 increased plant height when E. globulus were 14 weeks old and continued to do so at an accelerated rate compared to those grown at ambient CO2 (aCO2). Plants exposed to root-damaging insects showed a rapid decline in growth rates thereafter. In eCO2, shoot and root biomass increased by 46 and 35%, respectively, in insect-free plants but these effects were arrested when soil-dwelling insects were present so that plants were the same size as those grown at aCO2. Specific leaf mass increased by 29% under eCO2, but at eCO2 root damage caused it to decline by 16%, similar to values seen in plants at aCO2 without root damage. Leaf C:N ratio increased by >30% at eCO2 as a consequence of declining leaf N concentrations, but this change was also moderated by soil insects. Soil insects also reduced leaf water content by 9% at eCO2, which potentially arose through impaired water uptake by the roots. We hypothesise that this may have impaired photosynthetic activity to the extent that observed plant responses to eCO2 no longer occurred. In conclusion, soil-dwelling insects could modify plant responses to eCO2 predicted by climate change plant growth models.http://europepmc.org/articles/PMC3832529?pdf=render
spellingShingle Scott N Johnson
Markus Riegler
Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.
PLoS ONE
title Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.
title_full Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.
title_fullStr Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.
title_full_unstemmed Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.
title_short Root damage by insects reverses the effects of elevated atmospheric CO2 on Eucalypt seedlings.
title_sort root damage by insects reverses the effects of elevated atmospheric co2 on eucalypt seedlings
url http://europepmc.org/articles/PMC3832529?pdf=render
work_keys_str_mv AT scottnjohnson rootdamagebyinsectsreversestheeffectsofelevatedatmosphericco2oneucalyptseedlings
AT markusriegler rootdamagebyinsectsreversestheeffectsofelevatedatmosphericco2oneucalyptseedlings