Kreuzeder Andreas, Santner Jakob, Scharsching Vanessa, Oburger Eva, Hoefer Christoph, Hann Stephan, Wenzel Walter W
1Department of Forest and Soil Sciences, Institute of Soil Research, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, A-3430 Tulln, Austria.
Land Salzburg, Natur- und Umweltschutz, Gewerbe (Abteilung 5), Michael-Pacher-Straße 36, A-5020 Salzburg, Austria.
Plant Soil. 2018;424(1):573-589. doi: 10.1007/s11104-017-3542-0. Epub 2018 Jan 13.
We imaged the sub-mm distribution of labile P and pH in the rhizosphere of three plant species to localize zones and hot spots of P depletion and accumulation along individual root axes and to relate our findings to nutrient acquisition / root exudation strategies in P-limited conditions at different soil pH, and to mobilization pattern of other elements (Al, Fe, Ca, Mg, Mn) in the rhizosphere.
Sub-mm distributions of labile elemental patterns were sampled using diffusive gradients in thin films and analysed using laser ablation inductively coupled plasma mass spectrometry. pH images were taken using planar optodes.
We found distinct patterns of highly localized labile P depletion and accumulation reflecting the complex interaction of plant P acquisition strategies with soil pH, fertilizer treatment, root age, and elements (Al, Fe, Ca) that are involved in P biogeochemistry in soil. We show that the plants respond to P deficiency either by acidification or alkalization, depending on initial bulk soil pH and other factors of P solubility.
P solubilization activities of roots are highly localized, typically around root apices, but may also extend towards the extension / root hair zone.
我们对三种植物根际中不稳定磷（P）和pH的亚毫米分布进行成像，以定位沿单个根轴的磷消耗和积累区域及热点，并将我们的研究结果与不同土壤pH值下磷限制条件下的养分获取/根系分泌物策略相关联，以及与根际中其他元素（铝、铁、钙、镁、锰）的活化模式相关联。
使用薄膜中的扩散梯度对不稳定元素模式的亚毫米分布进行采样，并使用激光烧蚀电感耦合等离子体质谱法进行分析。使用平面光极获取pH图像。
我们发现了高度局部化的不稳定磷消耗和积累的独特模式，这反映了植物磷获取策略与土壤pH值、肥料处理、根龄以及参与土壤中磷生物地球化学的元素（铝、铁、钙）之间的复杂相互作用。我们表明，植物根据初始土壤pH值和磷溶解度的其他因素，通过酸化或碱化对磷缺乏做出反应。
根系的磷溶解活动高度局部化，通常围绕根尖，但也可能延伸至伸长区/根毛区。
