The impact of drought on leaf physiology of Quercus suber L. trees : comparison of an extreme drought event with chronic rainfall reduction

Understanding the responses of cork oak (Quercus suber L.) to actual and predicted summer conditions is essential to determine the future sustainability of cork oak woodlands in Iberia. Thermal imaging may provide a rapid method for monitoring the extent of stress. The ecophysiology of cork trees wa...

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Détails bibliographiques
Publié dans:Journal of experimental botany. - 1985. - 61(2010), 15 vom: 22. Okt., Seite 4361-71
Auteur principal: Grant, Olga M (Auteur)
Autres auteurs: Tronina, Lukasz, Ramalho, José Cochicho, Kurz Besson, Cathy, Lobo-do-Vale, Raquel, Santos Pereira, João, Jones, Hamlyn G, Chaves, M Manuela
Format: Article en ligne
Langue:English
Publié: 2010
Accès à la collection:Journal of experimental botany
Sujets:Comparative Study Journal Article Research Support, Non-U.S. Gov't Soil Water 059QF0KO0R Chlorophyll 1406-65-1
Description
Résumé:Understanding the responses of cork oak (Quercus suber L.) to actual and predicted summer conditions is essential to determine the future sustainability of cork oak woodlands in Iberia. Thermal imaging may provide a rapid method for monitoring the extent of stress. The ecophysiology of cork trees was studied over three years. Three treatments were applied by means of rainfall capture and irrigation, with plots receiving 120%, 100%, or 80% of natural precipitation. Despite stomatal closure, detected using both thermal imaging and porometry, leaf water potential fell during the summer, most drastically during the third year of accumulative stress. The quantum efficiency (ΦPSII) and the maximum efficiency Fv' /FM' of photosystem II also fell more intensely over the third summer, while non-photochemical quenching (NPQ) increased. The reduced precipitation treatment sporadically further reduced leaf water potential, stomatal conductance (gs), IG (an index of gs derived from thermal imaging), ΦPSII, and Fv' /FM', and increased leaf temperature and NPQ. It is concluded that these are very resilient trees since they were only severely affected in the third year of severe drought (the third year registering 45% less rainfall than average), and removing 20% of rainfall had a limited impact
Description:Date Completed 27.01.2011
Date Revised 08.04.2022
published: Print-Electronic
Citation Status MEDLINE
ISSN:1460-2431
DOI:10.1093/jxb/erq239