IMPACT OF HEAVY METALS ON PHYSIOLOGICAL AND PROTEOMIC RESPONSES OF WILLOWS (SALIX SP.)

In 2010, around 3,800 sites in Wallonia (Belgium) were identified as potentially contaminated by heavy metals, a result of their past industrial and agricultural activities [1]. The technique of using plants to remediate contaminated sites (phytoremediation) has been studied for over twenty years. In particular, the use of trees (alder, willow, poplar) has been considered because of their large biomass production [2] [3] [4] [5].
The aim of this study was to identify the potential of local willow ecotypes to grow in the presence of heavy metals using lysimeters filled with dredging sludge. Several willow ecotypes were compared realizing morphological and physiological measurements (chlorophyll fluorescence, electrolyte leakage, carbohydrate content). The plant responses to metal stress were also investigated using a proteomic approach. Heavy metals contents in leaves and stems were analysed. With this study, the potential of these trees to valorise contaminated, abandoned sites in Belgium was evaluated.

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