Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Water-use efficiency in cork oak (Quercus suber) is modified by the interaction of water and light availabilities
AU - Aranda, Ismael
AU - Pardos, Marta
AU - Puertolas Simon, Jaime
AU - Jimenez, Maria Dolores
AU - Pardos, Jose Alberto
PY - 2007/5
Y1 - 2007/5
N2 - We studied the interaction of light and water on water-use efficiency in cork oak (Quercus suber L.) seedlings. One-year-old cork oak seedlings were grown in pots in a factorial experiment with four light treatments (68, 50, 15 and 5% of full sunlight) and two irrigation regimes: well watered (WW) and moderate drought stress (WS). Leaf predawn water potential, which was measured at the end of each of two cycles, did not differ among the light treatments. Water-use efficiency, assessed by carbon isotope composition (delta C-13), tended to increase with increasing irradiance. The trend was similar in the WW and WS treatments, though with lower delta C-13 in all light treatments in the WW irrigation regime. Specific leaf area increased with decreasing irradiance, and was inversely correlated with delta C-13. Thus, changes in delta C-13 could be explained in part by light-induced modifications in leaf morphology. The relationship between stomatal conductance to water vapor and net photosynthesis on a leaf area basis confirmed that seedlings in higher irradiances maintained a higher rate of carbon uptake at a particular stomatal conductance, implying that shaded seedlings have a lower water-use efficiency that is unrelated to water availability.
AB - We studied the interaction of light and water on water-use efficiency in cork oak (Quercus suber L.) seedlings. One-year-old cork oak seedlings were grown in pots in a factorial experiment with four light treatments (68, 50, 15 and 5% of full sunlight) and two irrigation regimes: well watered (WW) and moderate drought stress (WS). Leaf predawn water potential, which was measured at the end of each of two cycles, did not differ among the light treatments. Water-use efficiency, assessed by carbon isotope composition (delta C-13), tended to increase with increasing irradiance. The trend was similar in the WW and WS treatments, though with lower delta C-13 in all light treatments in the WW irrigation regime. Specific leaf area increased with decreasing irradiance, and was inversely correlated with delta C-13. Thus, changes in delta C-13 could be explained in part by light-induced modifications in leaf morphology. The relationship between stomatal conductance to water vapor and net photosynthesis on a leaf area basis confirmed that seedlings in higher irradiances maintained a higher rate of carbon uptake at a particular stomatal conductance, implying that shaded seedlings have a lower water-use efficiency that is unrelated to water availability.
KW - photosynthesis
KW - uptake
KW - ACER-NEGUNDO
KW - NITROGEN CONCENTRATION
KW - stomatal conductance
KW - CO2 TRANSFER CONDUCTANCE
KW - water potential
KW - SYLVATICA L. SEEDLINGS
KW - carbon isotope composition
KW - drought
KW - LEAF DELTA-C-13
KW - PHYSIOLOGICAL-RESPONSES
KW - specific leaf area
KW - GAS-EXCHANGE
KW - shade
KW - PINUS-SYLVESTRIS L.
KW - PHOTOSYNTHETIC CAPACITY
KW - CARBON-ISOTOPE DISCRIMINATION
U2 - 10.1093/treephys/27.5.671
DO - 10.1093/treephys/27.5.671
M3 - Journal article
VL - 27
SP - 671
EP - 677
JO - Tree Physiology
JF - Tree Physiology
SN - 0829-318X
IS - 5
ER -