Availability of Zinc to Different Organic Ligands Under Reduced Conditions in Constrasting Rice Soils

Rice plants sometimes exude organic acids or phytosiderophores into the soil through the roots. These compounds chelate metal cations, such as Zn2+, increasing the availability for nutrient uptake by the plant. And because the chemistry of flooded soils causes many changes in the type and concentration of the cations that are present to react with these chelating compounds, it is expected that the effectiveness of root exudates to mobilize Zn will vary depending on soil conditions (Lombnaes et al 2008). It is therefore important to understand how these ligands interact with Zn in various soil types. The objective of the study was to extract Zn from farmers' fields from selected areas in the Philippines with contrasting properties to compare the extraction capacity of three ligands representing different types of root exudates.

水稻植株有时会通过根系向土壤中分泌有机酸或植物铁载体（phytosiderophores）。这类化合物可螯合Zn²+等金属阳离子，提升植物对该养分的吸收利用效率。由于淹水土壤的化学特性会使与其发生反应的阳离子的种类与浓度发生诸多变化，因此根系分泌物活化锌的效能会随土壤条件而异（Lombnaes等，2008）。因此，明确这些配体在不同土壤类型中与锌的相互作用机制至关重要。本研究的目标是从菲律宾选定区域的农户农田中采集土壤样本，这些农田的土壤性状存在显著差异，以此对比三类代表不同根系分泌物类型的配体对锌的提取能力。