Trees

, 20:713

Can CO2 enrichment modify the effect of water and high light stress on biomass allocation and relative growth rate of cork oak seedlings?

  • Marta Pardos
  • Jaime Puértolas
  • Ismael Aranda
  • J. A. Pardos
Original Article

DOI: 10.1007/s00468-006-0086-y

Cite this article as:
Pardos, M., Puértolas, J., Aranda, I. et al. Trees (2006) 20: 713. doi:10.1007/s00468-006-0086-y

Abstract

To test whether the impact of an enriched-CO2 environment on the growth and biomass allocation of first-season Quercus suber L. seedlings can modify the drought response under shade or sun conditions, seedlings were grown in pots at two CO2 concentrations × two watering regimes × two irradiances. Compared to CO2, light and water treatment had greater effects on all morphological traits measured (height, stem diameter, number of leaves, leaf area, biomass fractions). Cork oak showed particularly large increases in biomass in response to elevated CO2 under low-watered (W−) and high-illuminated conditions (L+). Allocation shifted from shoot to root under increasing irradiance (L+), but was not affected by CO2. Changes in allocation related to water limitation were only modest, and changed over time. Relative growth rate (RGR) and net assimilation rate (NAR) were significantly greatest in the L+/W+ treatment for both CO2 concentrations. Changes in RGR were mainly due to NAR. Growth responses to increased light, water or CO2 were strongest with light, medium with water availability and smallest for CO2, in terms of RGR. The rise in NAR for light and water treatments was counterbalanced by a decrease in SLA (specific leaf area) and LMF (leaf mass fraction). Results suggest that elevated CO2 caused cork oak seedlings to improve their performance in dry and high light environments to a greater extent than in well-irrigated and low light ones, thus ameliorating the effects of soil water stress and high light loads on growth.

Keywords

CO2 concentrationIrradianceWater regimeQuercus suberMorphological traitsAllometric analysisGrowth analysis

Abbreviations

RGR

Relative growth rate

NAR

Net assimilation rate

LMF

Leaf mass fraction

RMF

Root mass fraction

SMF

Stem mass fraction

GRC

Growth response coefficient

SLA

Specific leaf area

S/R

Shoot-to-root ratio

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Marta Pardos
    • 1
  • Jaime Puértolas
    • 2
    • 3
  • Ismael Aranda
    • 1
  • J. A. Pardos
    • 2
  1. 1.CIFOR-INIAMadridSpain
  2. 2.U.D. AnatomíaFisiología y Genética, ETSI Montes, UPMMadridSpain
  3. 3.Centro Nacional de Mejora Forestal “El Serranillo”DGBGuadalajaraSpain