Supplying nitrate before bud break induces pronounced changes in nitrogen nutrition and growth of young poplars
2012
Thitithanakul,, Suraphon | Petel, Gilles | Chalot, Michel | Beaujard, Francois, F. | Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF) ; Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP) | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)
Cited Reference Count: 42 ref.Csirohttp://www.publish.csiro.au/nid/[email protected]
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显示更多 [+] 显示较少 [-]英语. Tree nutrient research concentrated on endogenous C and N remobilisation in spring has neglected to acknowledge the possibilities of significant effects of N uptake before bud break, especially on the quality of regrowth and N reserve remobilisation. To investigate this subject, experimental studies were performed on young poplars (Populus tremula x Populus alba, clone INRA 717-1B4) grown with a controlled nutrient supply: (i) without N, 'control'; (ii) N supplied throughout the course of the experiment, 'N-supply'; and (iii) N supplied only before bud break, 'N-pulse'. Results confirm the hypothesis that poplar scions can significantly take up nitrate before bud break, amounting to similar to 34% of the total N stored the previous year. After bud break, emerging leaves restart the sap flow, which increased nitrate uptake to support the regrowth. N-pulse and N-supply treatments were found to have significant effects shortly after a growth period, i. e. by increasing N content of all tissues (e.g. 37 and 81% in new shoots respectively), leaf area (18 and 29%) and specific leaf area (20 and 35%). Therefore, results confirm the hypothesis that early N supply plays a significant role in the N status and N remobilisation involved in the spring regrowth of young trees.
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