<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tronina, L.</style></author><author><style face="normal" font="default" size="100%">Grant, O. M.</style></author><author><style face="normal" font="default" size="100%">Ramalho, J. C.</style></author><author><style face="normal" font="default" size="100%">Chaves, M. M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">USE OF THERMAL IMAGING TECHNIQUES AND XANTHOPHYLLS CONTENT FOR DETERMINATION OF STRESS IN CORK OAK (QUERCUS SUBER L.)</style></title><secondary-title><style face="normal" font="default" size="100%">ACTA PHYSIOLOGIAE PLANTARUM</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Quercus suber L.</style></keyword><keyword><style  face="normal" font="default" size="100%">Stress</style></keyword><keyword><style  face="normal" font="default" size="100%">thermal imaging</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2004</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2004///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">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 Formula 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 Formula, 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.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><notes><style face="normal" font="default" size="100%">Key words: ASKey words: ASThe following values have no corresponding Zotero field:&lt;br/&gt;pub-location: TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY&lt;br/&gt;publisher: SPRINGER HEIDELBERG</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">FARIA, T.</style></author><author><style face="normal" font="default" size="100%">Wilkins, D.</style></author><author><style face="normal" font="default" size="100%">Besford, R. T.</style></author><author><style face="normal" font="default" size="100%">Vaz, M.</style></author><author><style face="normal" font="default" size="100%">Pereira, J. S.</style></author><author><style face="normal" font="default" size="100%">Chaves, M. M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Growth at elevated CO2 leads to down-regulation of photosynthesis and altered response to high temperature in Quercus suber L. seedlings</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Experimental Botany</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">acclimation</style></keyword><keyword><style  face="normal" font="default" size="100%">Elevated CO2</style></keyword><keyword><style  face="normal" font="default" size="100%">photo- synthesis</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber L.</style></keyword><keyword><style  face="normal" font="default" size="100%">Temperature</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1996</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1996///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://jxb.oxfordjournals.org/content/47/11/1755.abstract</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">1755 - 1761</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of growth at elevated CO2 on the response to high temperatures in terms of carbon assimilation (net photosynthesis, stomatal conductance, amount and activity of Rubisco, and concentrations of total soluble sugars and starch) and of photochemistry (for example, the efficiency of excitation energy captured by open photosystem II reaction centres) were studied in cork oak (Quercus suber L.). Plants grown in elevated CO2 (700 ppm) showed a down-regulation of photosynthesis and had lower amounts and activity of Rubisco than plants grown at ambient CO2 (350 ppm), after 14 months in the greenhouse. At that time plants were subjected to a heat-shock treatment (4 h at 45°C in a chamber with 80% relative humidity and 800–1000 µmol m−2 s−1 photon flux density). Growth in a CO2-enriched atmosphere seems to protect cork oak leaves from the short-term effects of high temperature. Elevated CO2 plants had positive net carbon uptake rates during the heat shock treatment whereas plants grown at ambient CO2 showed negative rates. Moreover, recovery was faster in high CO2-grown plants which, after 30 min at 25°C, exhibited higher net carbon uptake rates and lower decreases in photosynthetic capacity (Amax as well as in the efficiency of excitation energy captured by open photosystem II reaction centres (FvJFm than plants grown at ambient CO2. The stomata of elevated CO2 plants were also less responsive when exposed to high temperature.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><notes><style face="normal" font="default" size="100%">10.1093/jxb/47.11.175510.1093/jxb/47.11.1755</style></notes></record></records></xml>