Integration of XAS techniques and genetic methodologies to explore Cs-tolerance in Arabidopsis

We have characterised genetically and phenotypically a T-DNA insertion mutant line of A. thaliana (L.) Heynh. selected for Cs resistance when germinating and growing on Cs concentrations up to 600 μM, lethal for the wild type. Measures of concentration and localisation of Cs, K, and Ca have been conducted on plants grown in vivo also utilising synchrotron light-based techniques as μ-SRXF (synchrotron radiation induced X-ray micro-fluorescence) and μ-XANES (micro X-ray absorption near edge structure) spectroscopy. We report here an attempt to apply μ-XANES to investigate Cs speciation and to measure the Cs content of living plants. The results obtained with μ-SRXF and μ-XANES spectroscopy complemented the genetic and physiological analyses: a comparison between wild type and mutant plants led to the conclusion that in our case a single gene mutation impairs Cs uptake and translocation, K and Ca homeostasis and plant biomass production.