tailieunhanh - Báo cáo lâm nghiệp: "Influence of flooding on growth, nitrogen availability in soil, and nitrate reduction of young oak seedlings (Quercus robur L.)"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài:"Influence of flooding on growth, nitrogen availability in soil, and nitrate reduction of young oak seedlings (Quercus robur L.)" | Ann. For. Sci. 62 2005 593-600 593 INRA EDP Sciences 2005 DOI forest 2005052 Original article Influence of flooding on growth nitrogen availability in soil and nitrate reduction of young oak seedlings Quercus robur L. Badr Alaoui-Sossé Bastien GÉRARD Philippe Binet Marie-Laure Toussaint Pierre-Marie Badot Université de Franche-Comté - INRA Laboratoire de Biologie Environnementale BP 71427 4 place Tharradin 25211 Montbéliard Cedex France Received 4 March 2004 accepted 28 January 2005 Abstract - Oak Quercus robur L. seedlings were grown in pots under controlled conditions and submitted to 34 days of flooding followed by two-week drainage. Roots were significantly affected with reduced extension and dry weight accumulation. After drainage biomass production of adventitious roots markedly increased in flooded seedlings. Flooding induced a sharp decrease in NO3--N content in the soil especially in the bottom of pots. NH -N concentrations increased significantly but at less level compared to NO3 -N decreases. During flooding root nitrate reductase activity NRA was similar to controls while leaf NRA was always below that of controls. The flooded roots maintained amino acid synthesis despite the nitrate depletion in soil. By contrast leaf amino acid content decreased significantly in flooded seedlings especially at day 34. In flooded seedlings the transfer of amino acid from cotyledons was disrupted but the transfer capacity was restored after drainage. Relationships between nitrate reduction and changes in soil mineral nitrogen availability are discussed. flooding mineral nitrogen availability nitrate reduction Quercus robur L. Résumé - Influence de l ennoyage sur la croissance la biodisponibilité en azote du sol et sur la reduction des nitrates chez de jeunes semis de chêne pédonculé Quercus robur L. . Des semis de chêne pédonculé Quercus robur L. cultivés en conditions contrôlées ont été soumis à 34 jours d ennoyage suivi de deux semaines de drainage. La .