<?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%">Gabriel, Reinhard</style></author><author><style face="normal" font="default" size="100%">Kesselmeier, Jürgen</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Apoplastic Solute Concentrations of Organic Acids and Mineral Nutrients in the Leaves of Several Fagaceae</style></title><secondary-title><style face="normal" font="default" size="100%">Plant and Cell Physiology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Anions</style></keyword><keyword><style  face="normal" font="default" size="100%">Apoplast</style></keyword><keyword><style  face="normal" font="default" size="100%">cations</style></keyword><keyword><style  face="normal" font="default" size="100%">Fagaceae</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf</style></keyword><keyword><style  face="normal" font="default" size="100%">organic acids</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1999</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1999///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://pcp.oxfordjournals.org/content/40/6/604.abstract</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">40</style></volume><pages><style face="normal" font="default" size="100%">604 - 612</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Ion chromatographic methods determined organic acids and main nutrient minerals in the apoplastic solution from leaves of several Fagaceae (Quercus ilex L., Quercus cerris L., Quercus virgiliana (Ten.) Ten, and Fagus sylvatica L.). The anions of organic acids found in high amounts (250 to 650 μM) were quinate, malate, and oxalate. Lactate, pyruvate, formate and acetate were detected in relatively low amounts with concentrations between 20 and 200 μM. The total concentration of organic acids in the apoplastic sap ranged between 1.5 and 2 mM. The total concentration of inorganic cations (K+, Mg2+, NH4+, Ca2+, Na+) and anions (C1−, NO3−, SO2−4 and PO3−4) in the apoplastic sap varied between 5 and 10 mM, and 0.35 and 1.8 mM, respectively. We conclude that the concentration of organic acid ions in the leaf apoplast depends mainly on the exchange with the leaf cells and is influenced by the electrochemical gradient between the symplast and the apoplast in relation to the water potential of the leaf. The determination of formate and acetate in the apoplastic compartment of leaves lend weight to the argument that the production of these acids by trees is a important emission source to the atmosphere.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue></record><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%">Courtois, Michèle</style></author><author><style face="normal" font="default" size="100%">Masson, Philippe</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Relations entre la qualité du liège, sa composition minérale et la composition minérale des feuilles du chêne-liège (Quercus suber L.)</style></title><secondary-title><style face="normal" font="default" size="100%">Ann. For. Sci.</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">inorganic content</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf</style></keyword><keyword><style  face="normal" font="default" size="100%">Quality</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus Suber L</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1999</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1999///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1051/forest:19990609</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">56</style></volume><pages><style face="normal" font="default" size="100%">521 - 527</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Relationships between the quality of cork, its inorganic content and the inorganic content of the leaves of the cork-oak (Quercus suber L.). The aim of this work is to set up a relationship between the quality of cork, its inorganic content and the inorganic content of the leaves of the cork-oak. The mineral contents of both leaves and cork were identified for a range of elements (nitrogen, phosphorus, potassium, calcium, magnesium, iron, copper, zinc and manganese). The quality of the cork was evaluated by experts in the cork industry on the basis of visual assessment of cork stoppers resulting from each tree. A study of correlations between the cork inorganic contents and the quality of cork demonstrates that, among those measures, only the potassium content of cork is related to the cork quality. The cork quality seems to be independent of the leaf inorganic content, which is held to be an indicator of the cork-oak mineral nutrition. (© Inra/Elsevier, Paris.)</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue></record></records></xml>