دورية أكاديمية
Effects of N availability, local light regime and leaf rank on the amount and sources of N allocated within the foliage of young walnut (Juglans nigra x regia) trees
| العنوان: | Effects of N availability, local light regime and leaf rank on the amount and sources of N allocated within the foliage of young walnut (Juglans nigra x regia) trees |
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| المؤلفون: | Frak, Ela, Le Roux, Xavier, Millard, Peter, Guillaumie, Sabine, Wendler, Renate |
| المساهمون: | 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), Unité de recherche d'Écophysiologie des Plantes Fourragères (UEPF), Institut National de la Recherche Agronomique (INRA), Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Ecole Nationale Vétérinaire de Lyon (ENVL)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Macaulay Institute, Unité de recherche Génétique et Amélioration des Plantes Fourragères (UGAPF) |
| المصدر: | ISSN: 0829-318X. |
| بيانات النشر: | HAL CCSD Oxford University Press (OUP) |
| سنة النشر: | 2006 |
| المجموعة: | HAL Lyon 1 (University Claude Bernard Lyon 1) |
| مصطلحات موضوعية: | leaf N, N allocation, N remobilization, N uptake, 15N, shading, [SDV.BID]Life Sciences [q-bio]/Biodiversity, [SDV.EE]Life Sciences [q-bio]/Ecology, environment |
| الوصف: | Early season leaf growth depends largely on N provided by remobilization from storage and many studies have tested the impact of current-N availability to roots on the amount of leaf N provided by remobilization. While it is well known that the light regime experienced by a leaf influences the amount of N per unit leaf area, the effects on N derived from direct root uptake or remobilization have never been tested at an intra-canopy scale. The objective of this study was to quantify the relative importance of (i) N availability to roots, (ii) local light regime experienced by the foliage (here at shoot scale), and (iii) leaf rank along the shoot, on the total amount of N allocated to leaves and on the proportions of N provided by remobilization and uptake. Potted hybrid walnut trees (Juglans nigra x regia L.) were grown outdoors in sand and fed with a labelled (15N) nutrient solution in order to quantify the importance of uptake and remobilization as sources for leaf N. The trees were manipulated to produce only two shoots by removing the apical bud and an experimental design with two factors was used: (1) N availability for the tree (8 mol N m-3, HN, or 2 mol N m-3, LN), and (2) light level of treated (lower) branch (90%, HL, or 10%, LL, of incident light). Total leaf N per individual tree was not influenced by either N availability or light level. Higher N availability increased the amount of leaf N derived from root uptake at the whole - tree scale (typically around 8% and 2% under HN and LN, respectively). N allocation within the foliage of individual trees was controlled by the local light regime that strongly affected individual leaf characteristics (Ma and Na). Decreasing the light availability to a branch decreased the amount of N allocated to this branch to the benefit of the less shaded branch. In contrast, the local light regime (shading) experienced by the lower branch did not affect the fraction of total leaf N provided by remobilization for both lower, shaded or upper, unshaded branches. These ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| العلاقة: | hal-00124659; https://hal.science/hal-00124659Test; PRODINRA: 251829 |
| الإتاحة: | https://hal.science/hal-00124659Test |
| رقم الانضمام: | edsbas.421F523 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |