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

摘要: Predicted increases in atmospheric carbon dioxide (CO2) are widely anticipated to increase biomass accumulation by accelerating rates of photosynthesis many plant taxa. Little, however, is known about how soil-borne antagonists might modify the effects elevated CO2 (eCO2), with root-feeding insects being particularly understudied. Root damage often reduces disrupting root function and imposing water deficits. These therefore have considerable potential for modifying responses eCO2. We investigated a soil-dwelling insect (Xylotrupes gideon australicus) modified Eucalyptus globulus eCO2 increased height when E. were 14 weeks old continued do so at an accelerated rate compared those grown ambient (aCO2). Plants exposed root-damaging showed rapid decline growth thereafter. In eCO2, shoot 46 35%, respectively, insect-free plants but these arrested present that same size as aCO2. Specific leaf mass 29% under caused it 16%, similar values seen aCO2 without damage. Leaf C:N ratio >30% consequence declining N concentrations, this change was also moderated soil insects. Soil reduced content 9% which potentially arose through impaired uptake roots. hypothesise may photosynthetic activity extent observed no longer occurred. conclusion, could predicted climate models.