<?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%">Méthy, M</style></author><author><style face="normal" font="default" size="100%">Trabaud, L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Seasonal courses of photosynthetic activity and sublethal temperature tolerance of Quercus ilex leaves</style></title><secondary-title><style face="normal" font="default" size="100%">Forest Ecology and Management</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%">leaves</style></keyword><keyword><style  face="normal" font="default" size="100%">photosynthetic apparatus</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex (PG)</style></keyword><keyword><style  face="normal" font="default" size="100%">thermal stress</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1993</style></year></dates><volume><style face="normal" font="default" size="100%">61</style></volume><pages><style face="normal" font="default" size="100%">339-348</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The reaction of the photosynthetic system of a sclerophyllous tree of the Mediterranean region (Quercus ilex) to three temperature levels (one ambient and two sublethal) was analysed monthly for 1 year. Measurements were carried out on leaves less than 3 months old as well as on leaves older than 3 months by laser-induced chlorophyll fluorescence. Treatments were: control (unheated), 50°C for 30 min, and 60°C 10 min. Both for unheated and treated leaves the vitality index shows a seasonal course depending on the treatments. At 50°C the photosynthetic apparatus of leaves of the two ages is moderately affected. At 60°C the apparatus is severely damaged whatever the season and is unable to recover. The consequences for the management of Q. ilex forests in relation to some thermal stresses are considered.</style></abstract></record></records></xml>