RT info:eu-repo/semantics/article
T1 Foliar absorption and root translocation of nitrogen from different chemical forms in seedlings of two Mediterranean trees.
A1 Uscola Fernández, María Mercedes
A1 Oliet Palá, Juan Antonio
A1 Villar Salvador, Pedro
A1 Warren , Charles
K1 Ammonium-nitrate
K1 Cuticular conductance
K1 Glycine
K1 Pinus halepensis
K1 Quercus ilex
K1 Urea
K1 Medio Ambiente
K1 Environmental science
AB Along with root uptake, plants can also absorb N through leaves. There are few comparative studieson the foliar absorption of N from different chemical forms of N in forest tree species. We comparedthe foliar N absorption capacity in seedlings of two forest trees widespread in the Mediterranean basin,Quercus ilex and Pinus halepensis. Plants were sprayed with the following individual N forms at 40 mMN:15N-nitrate (NO3−),15N-ammonium (NH4+),15N-urea or13C and15N dual-labeled glycine. Cuticularconductance was used as a surrogate of cuticle permeability to water. Q. ilex had higher N foliar absorp-tion than P. hapelensis. Neither cuticular conductance nor shoot surface area explained N differences inabsorption rate between species, which were instead likely linked to differences in stomatal density andpresence of trichomes. In both species, foliar N absorption rate and N recovery differed among N forms:urea > NH4+≥ glycine ≥ NO3−. Differences in N absorption rate among N forms were correlated with theirphysico-chemical properties. The strong positive relationship between15N and13C uptake together withdetection in shoots of intact dual-labeled glycine (measured by gas chromatography&#-mass spectrome-try), indicated that a significant fraction of glycine was absorbed intact by the seedlings. In both species,higher cuticular conductance was related to faster N absorption from all forms except NO3&;8722#. Cuticularconductance had a stronger effect on N absorption from urea and NH4+than N absorption from glycine,and the effects were more intense in Q. ilex than in P. halepensis.
SN 0098-8472
YR 2014
FD 2014
LK http://hdl.handle.net/10017/37386
UL http://hdl.handle.net/10017/37386
LA eng
NO Comunidad de Madrid
DS MINDS@UW
RD 26-abr-2024