Photoinhibition in cork-oak leaves under stress: influence of the bark-stripping on the chlorophyll fluorescence emission inQuercus suber L. |
| |
Authors: | Christiane Werner Otília Correia |
| |
Institution: | 1. Botanisches Institut der Universit?t K?ln, III Lehrstuhl, Gyrhofstrasse 15, D-50923, K?ln, Germany 3. Departamento de Biologia Vegetal, Faculdade de Ciências de Lisboa, Campo Grande, C2, P-1700, Lisbon, Portugal
|
| |
Abstract: | Quercus suber is the primary source for industrial cork and becomes bark-stripped every 9–10 years. Recurring cork extraction is a major
stress factor and the large water loss from the stripped trunk surface may affect the water balance and tree productivity.
To evaluate the effect of bark-stripping, fluorescence emission and stomatal conductance of leaves were determined in groups
of bark-stripped and control trees. Fv/Fm ratio was found to be significantly lower in bark-stripped trees indicating a reduced
photosynthetic efficiency of PSII. Photosynthesis was not found to be stomata limited. The reduction in Fv/Fm resulted from
a decline in maximum and variable fluorescence while the initial fluorescence of the dark-adapted state (Fo) remained constant.
A general decline in photosynthetic efficiency of PSII was found in all trees during the summer, probably reflecting the prolonged
environmental stresses during a hot and dry season. Additional stress caused by the bark-stripping seems to enhance the susceptibility
to photoinhibition of the trees. |
| |
Keywords: | Bark-stripping Fluorescence emission Quercus suber L Water relations |
本文献已被 SpringerLink 等数据库收录! |
|