Early Response of Willow to Increasing Silver Concentration Exposure

Abstract

This is a preliminary hydroponic study to test willow sensitivity to silver nitrate, a highly toxic chemical compound. We grew willow cuttings for a period of three weeks in the presence of increasing AgNO₃ concentrations and assessed the response in terms of growth and physiology. We found that AgNO₃ is generally extremely harmful to willow. AgNO₃ concentration as high as 0.027 μM may result in a significant reduction of biomass productivity and a decrease in stomatal conductance over the first week of exposure. However, willows seem able to adapt to high AgNO₃ concentrations on a longer timeline.

KEY WORDS:

• Ag
• heavy metals
• phytoremediation
• salix

ACKNOWLEDGMENTS

The authors would like to thank four precious collaborators: Dr. Emmanuel Gonzalez for help with several issues related to silver chemistry; Stéphane Daigle for assistance with statistical analysis and interpretation of the results; Louise Pelletier for SEM pictures of tip root samples; and Karen Grislis for review of the English style of the manuscript.

Color versions of one or more of the figures in the article can be found online at www.tandfonline/bijp.