<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mata, C.</style></author><author><style face="normal" font="default" size="100%">Scheurwater, I.</style></author><author><style face="normal" font="default" size="100%">MartinsLoucao, M. A.</style></author><author><style face="normal" font="default" size="100%">Lambers, H.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Root respiration, growth and nitrogen uptake of Quercus suber seedlings</style></title><secondary-title><style face="normal" font="default" size="100%">PLANT PHYSIOLOGY AND BIOCHEMISTRY</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">NO3-; NH4+; relative growth rate; root respiration</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1996</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1996///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">34</style></volume><pages><style face="normal" font="default" size="100%">727 - 734</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We tested the influence of two N-sources, NO3- and NH4+, on root growthand respiration of Quercus suber L. Seedlings were grown on hydroponics
with 0.5 mM N as NO3- or NH4+ in a growth chamber. Root relative growth
rate (RGR) of NO3--fed seedlings ranged from 9 to 34 mg g(-1) day(-1).
These values are lower than those described for slow-growing herbaceous
and for most woody species. Root respiration and the activity and
capacity of the alternative pathway (AP) showed no differences between
the two N-sources. Both activity and capacity of the AP were very low
and the cytochrome pathway was fully engaged. Specific respiratory costs
were calculated for maintenance, 6.3 nmol O-2 g(-1) s(-1), for nitrate
uptake, 0.99 mol O-2 mol N-1, and for growth 5.4 mmol O-2 g(-1). These
values are similar to those found for slow-growing herbaceous species.
The major part of total root respiration, over 64%, was used for
maintenance processes, and a much smaller fraction for growth and
nitrate uptake.
</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;pub-location: S P E S-JOURNAL DEPT, 120 BD ST GERMAIN, F-75006 PARIS, FRANCE&lt;br/&gt;publisher: GAUTHIER-VILLARS</style></notes></record></records></xml>