Claim · model-written summary
Photorespiration in holm oak likely increased in response to water stress.
- Taxon
- Quercus ilex
Quercus ilexe0 - Treatment
- water stresse1
- Outcome
- photorespiratione1
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleComparatorSettingDirectionValueQualifier
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Diffusional limitations to photosynthesis (A), relative water content (RWC) and their association with photochemical reflectance index (PRI) were studied in holm oak (Quercus ilex L.) saplings subjected to water stress and subsequent water stress relief”
e1“As water stress progressed, A measured in non-photorespiratory conditions (A1%O2) became more than 3 times higher compared to that recorded at 21% [O2], indicating that photorespiration likely increased in response to water stress”
Title
Tsonko Tsonev; Said Wahbi; Pengsen Sun; et al. International Journal of Agriculture and Biology 2014
Other claims from this paper (15)
- Intervention effect Relative water content of holm oak decreased sharply as drought progressed.
- Intervention effect After rewatering, relative water content of holm oak gradually increased back to pre-stress values.
- Association Net photosynthesis, stomatal conductance and mesophyll conductance of holm oak changed in parallel with relative water content; the direction is not stated.
- Association Total conductance and PRI of holm oak changed in parallel with relative water content; the direction is not stated.
- Mechanism A decrease in photosynthesis in holm oak resulted from coordinated suppression of leaf conductance.
- Intervention effect Under water stress, photosynthesis measured without photorespiration (1% O2) in holm oak became more than 3 times higher than at 21% O2.
- Association Photosynthesis without photorespiration (A1%O2) in holm oak was significantly correlated with all leaf conductances.
- Association Photosynthesis without photorespiration (A1%O2) in holm oak was more limited by stomatal conductance (gs) than by mesophyll conductance (gm).
- Mechanism Higher mesophyll conductance favours photosynthesis over photorespiration in holm oak.
- Association Relative water content and PRI of holm oak were significantly linearly correlated.
- Association PRI and photosynthesis, and PRI and total conductance of holm oak, were related by significant non-linear relationships.
- Method / resource PRI may clearly detect normal and stressed status of holm oak, but is not very informative when plants are severely stressed.
- Method / resource The authors state that PRI is an important indicator of leaf water status in holm oak, as evident from relative water content.
- Association Holm oak would respond to future elevated CO2 significantly more than mesophyllous plants, because its leaf conductance does not limit photosynthesis when photorespiration is suppressed.
- Method / resource PRI can be used to predict changes in the performance of holm oak under physiological water stress, with caution needed under severe drought.