Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Effect of fungal infection on leaf gas-exchange and chlorophyll fluorescence in Quercus ilex. | 165 Ann. For. Sci. 58 2001 165-173 INRA EDP Sciences 2001 Original article Effect of fungal infection on leaf gas-exchange and chlorophyll fluorescence in Quercus ilex Bouchra El Omari Isabel Fleck Xavier Aranda Asumpció Moret and Martí Nadal Unitat de Fisiologia Vegetal Departament de Biologia Vegetal Facultat de Biologia Universitat de Barcelona Diagonal 645 08028 Barcelona Spain Received 17 January 2000 accepted 14 September 2000 Abstract - Experiments were conducted to study the susceptibility to infection by two fungal pathogens Cryphonectria parasitica or Phomopsis spp. of undisturbed holm oaks Quercus ilex and the resprout from the stump of trees after excision of the shoot. Leaf gas-exchange and chlorophyll a fluorescence were recorded on plants growing in natural conditions for two years as markers of disease progress at the first stages of infection. In infected plants pathogen-induced stomatal closure limited photosynthesis and increased contribution of energy dissipating processes protecting PSII integrity as shown by higher non-photochemical quenching NPQ . Excision treatment reduced susceptibility to infection and favoured water availability in resprouts which showed higher gasexchange rates. Quercus ilex Cryphonectriaparasitica Phomopsis spp. gas-exchange chlorophyll fluorescence Résumé - Effet de l infection fongique sur les échanges gazeux et la fluorescence de la chlorophylle chez Quercus ilex. Le but de ce travail est l etude de la susceptibilité des plants élagués cas du chêne vert à l infection par Cryphonectria parasitica et Phomopsis spp. Pendant deux années les échanges gazeux et la fluorescence de la chlorophylle d un groupe de plants croissants dans des conditions environnementales naturelles ont été étudiés. Ces paramètres ont été des marqueurs convenables de l évolution de la maladie durant les premières étapes de l infection. Chez les plants infectés le progrès de la maladie a été mis en évidence par la reduction de l assimilation de .
