<?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%">Mhamdi, Samah</style></author><author><style face="normal" font="default" size="100%">Brendel, Oliver</style></author><author><style face="normal" font="default" size="100%">Montpied, Pierre</style></author><author><style face="normal" font="default" size="100%">Ghouil-Amimi, Hanah</style></author><author><style face="normal" font="default" size="100%">Hasnaoui, Ibrahim</style></author><author><style face="normal" font="default" size="100%">Dreyer, Erwin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf morphology displays no detectable spatial organisation in the relict Quercus afares Pomel compared to the co-occurring parental species Q. canariensis Willd. and Q. suber L</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of Forest Science</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Endemic oak species</style></keyword><keyword><style  face="normal" font="default" size="100%">Hybridization</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf morphology</style></keyword><keyword><style  face="normal" font="default" size="100%">Mixed oak stands</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year></dates><publisher><style face="normal" font="default" size="100%">Springer Paris</style></publisher><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">675-684</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">•Context Oak species display a large within-species diversity combined with significant gene flow between species. Quercus afares Pomel is an endemic species that grows as a small relict population in Northern Tunisia, together with Quercus suber L. and Quercus canariensis Willd. It is considered to be a fixed hybrid between the two latter. •Aims We tested (1) whether this population of Q. afares is declining with respect to the neighbouring populations of the two other species and (2) whether the spatial distribution of leaf morphology is random among individuals within this small population of Q. afares or influenced by the neighbouring species. •Methods Spatial distribution and diameter at breast height were recorded in the population of Q. afares. We identified two perpendicular transects across the population reaching from areas dominated by Q. canariensis to areas dominated by Q. suber and defined 20 plots along each. Eleven traits were assessed on 10 leaves collected from the upper crown of trees from the three species. A multiple correspondence analysis and an ANOVA were used to test for within and between-species diversity in leaf morphology. •Results Q. afares individuals occurred at a low frequency among the two other species. Nevertheless, Q. afares showed no particular evidence of decline with respect to the two other species. Leaf traits displayed a large inter-specific variability with very little overlap between Q. afares and Q. suber and some between Q. afares and Q. canariensis. A high level of diversity was detected for these traits within Q. afares, but we were unable to unravel any spatial organisation of this diversity; in Q. afares, leaf traits varied independently of the presence of neighbouring Q. suber or Q. canariensis. •Conclusion Q. afares seems to be a fixed species with specific leaf traits that are independent of that of the species of the neighbouring trees. This population is not suffering a detectable trend towards decline except for the lack of any visible regeneration below any of the three species.</style></abstract></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%">Ghouil, Hana</style></author><author><style face="normal" font="default" size="100%">Montpied, Pierre</style></author><author><style face="normal" font="default" size="100%">Epron, Daniel</style></author><author><style face="normal" font="default" size="100%">Ksontini, Mustapha</style></author><author><style face="normal" font="default" size="100%">Hanchi, Belkacem</style></author><author><style face="normal" font="default" size="100%">Dreyer, Erwin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Thermal optima of photosynthetic functions and thermostability of photochemistry in cork oak seedlings</style></title><secondary-title><style face="normal" font="default" size="100%">Tree Physiology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">chlorophyll fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">Gas exchange</style></keyword><keyword><style  face="normal" font="default" size="100%">maximal carboxylation rate</style></keyword><keyword><style  face="normal" font="default" size="100%">maximal light-driven electron flow</style></keyword><keyword><style  face="normal" font="default" size="100%">Regeneration</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2003</style></year></dates><volume><style face="normal" font="default" size="100%">23</style></volume><pages><style face="normal" font="default" size="100%">1031-1039</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Temperature effects on photosynthesis were studied in seedlings of evergreen Mediterranean cork oak (Quercus suber L.). Responses to changes in temperature and the temperature optima of maximal carboxylation rate (Vcmax) and maximal light-driven electron flux (Jmax) were estimated from gas exchange measurements and a leaf-level photosynthesis model. The estimated temperature optima were approximately 34 and 33 °C for Vcmax and Jmax, respectively, which fall within the lower range of temperature optima previously observed in deciduous tree species. The thermostability of the photosynthetic apparatus was estimated according to the temperature at which basal chlorophyll a fluorescence begins to increase (Tc). The Tc was highly variable, increasing from 42 to 51 °C when ambient temperature rose from 10 to 40 °C, and increasing from 44 to 54 °C with decreasing soil water availability while net CO2 assimilation rate dropped to almost zero. When a heat shock was imposed, an additional small increase in Tc was observed in drought-stressed and control seedlings. Maximal Tc values following heat shock were about 56 °C, which, to our knowledge, are the highest values that have been observed in tree species. In conclusion, the intrinsic temperature responses of cork oak did not differ from those of other species (similar Tc under ambient temperature and water availability, and relatively low thermal optima for photosynthetic capacity in seedlings grown at cool temperatures). However, the large ability of cork oak to acclimate to drought and elevated temperature may be an important factor in the tolerance of this evergreen Mediterranean species to summer drought and high temperatures.</style></abstract><notes><style face="normal" font="default" size="100%">10.1093/treephys/23.15.1031</style></notes><research-notes><style face="normal" font="default" size="100%">10.1093/treephys/23.15.1031</style></research-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%">Ghouil, Hana</style></author><author><style face="normal" font="default" size="100%">Montpied, Pierre</style></author><author><style face="normal" font="default" size="100%">Epron, Daniel</style></author><author><style face="normal" font="default" size="100%">Ksontini, Mustapha</style></author><author><style face="normal" font="default" size="100%">Hanchi, Belkacem</style></author><author><style face="normal" font="default" size="100%">Dreyer, Erwin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Thermal optima of photosynthetic functions and thermostability of photochemistry in cork oak seedlings</style></title><secondary-title><style face="normal" font="default" size="100%">Tree Physiology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">chlorophyll fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">Gas exchange</style></keyword><keyword><style  face="normal" font="default" size="100%">maximal carboxylation rate</style></keyword><keyword><style  face="normal" font="default" size="100%">maximal light-driven electron flow</style></keyword><keyword><style  face="normal" font="default" size="100%">Regeneration</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2003</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2003///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://treephys.oxfordjournals.org/content/23/15/1031.abstract</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">23</style></volume><pages><style face="normal" font="default" size="100%">1031 - 1039</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Temperature effects on photosynthesis were studied in seedlings of evergreen Mediterranean cork oak (Quercus suber L.). Responses to changes in temperature and the temperature optima of maximal carboxylation rate (Vcmax) and maximal light-driven electron flux (Jmax) were estimated from gas exchange measurements and a leaf-level photosynthesis model. The estimated temperature optima were approximately 34 and 33 °C for Vcmax and Jmax, respectively, which fall within the lower range of temperature optima previously observed in deciduous tree species. The thermostability of the photosynthetic apparatus was estimated according to the temperature at which basal chlorophyll a fluorescence begins to increase (Tc). The Tc was highly variable, increasing from 42 to 51 °C when ambient temperature rose from 10 to 40 °C, and increasing from 44 to 54 °C with decreasing soil water availability while net CO2 assimilation rate dropped to almost zero. When a heat shock was imposed, an additional small increase in Tc was observed in drought-stressed and control seedlings. Maximal Tc values following heat shock were about 56 °C, which, to our knowledge, are the highest values that have been observed in tree species. In conclusion, the intrinsic temperature responses of cork oak did not differ from those of other species (similar Tc under ambient temperature and water availability, and relatively low thermal optima for photosynthetic capacity in seedlings grown at cool temperatures). However, the large ability of cork oak to acclimate to drought and elevated temperature may be an important factor in the tolerance of this evergreen Mediterranean species to summer drought and high temperatures.</style></abstract><issue><style face="normal" font="default" size="100%">15</style></issue><notes><style face="normal" font="default" size="100%">10.1093/treephys/23.15.103110.1093/treephys/23.15.1031</style></notes></record></records></xml>