|MadSci Network: Botany|
Cesium is chemically similar to potassium. Potassium is essential to plants. Cesium is not essential for plants and is toxic at high enough concentrations. Cesium binds to potassium binding sites on proteins (Hampton et al. 2004). Potassium is not incorporated into specific molecules as are many essential elements such as nitrogen, phosphorus and sulfur. Potassium occurs in plants as the soluble potassium ion. More potassium occurs in vacuoles than in the cytosol. In mesophyll cells of wheat leaves, potassium activity was 235 mM in the vacuole and 79 mM in the cytosol (Cuin et al. 2003). Cesium would be expected to behave similarly. Potassium functions to activate certain enzymes, is required for stomatal opening and functions as an osmoticum. Search PubMed or Science Citation Index for more information on cesium and plants. References Hampton, C.R., Bowen, H.C., Broadley, M.R., Hammond, J.P., Mead, A., Payne, K.A., Pritchard, J. and White, P.J. 2004. Cesium toxicity in Arabidopsis. Plant Physiology 136:3824-3837. Cuin, T.A., Miller, A.J.,Laurie, S.A. and Leigh, R.A. 2003. Potassium activities in cell compartments of salt-grown barley leaves. Journal of Experimental Botany 54: 657-661. Essential Elements for Plant Growth: Potassium PubMed The importance of potassium to plants
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