Popis: |
Plant survival depends on the ability of root systems to establish themselves in locations where water and nutrients are available for uptake and translocation (Hawes et al., 2003). Rhizosphere influences crop productivity by mediating efficient nutrient transformation, acquisition, and use (Shen et al., 2013). Rhizosphere acidification is a central mechanism for plant mineral nutrition since it contributes to nutrient solubility and the proton motive force (pmf). This pmf is generated by the plasma membrane H+-ATPases (Miller and Smith, 1996; Forde, 2000) in root epidermal and cortical cells, and is coupled to active nutrient acquisition (e.g., N, K, P). Roots are able to acidify the rhizosphere by up to two pH units compared to the surrounding bulk soil mainly through the release of protons, but also bicarbonate, organic acids and CO2. Here we present an easy and inexpensive protocol to quantify protons released to the media by the root system-a method successfully used in our recently published work (Pizzio et al., 2015). |