Response of Arabidopsis thaliana to Exposure to Pentachlorophenol and Influence of Boron

Abstract

Pentachlorophenol (PCP) has recently been used in combination with boric acid to provide a dual treatment wood preservative for utility poles. The toxicity of chemical combinations of PCP and boric acid were examined with bioassays using the model plant Arabidopsis thaliana to generate both a quantifiable phenotypic and genetic response as potential biomarkers for PCP toxicity. Boric acid was not observed to have any significant effect on PCP toxicity. Fresh weight was determined to be the most consistent biomarker within this study of PCP toxicity with an EC50 of 5.32 mg/L. The induction of cytochrome P450 gene AT5G36220 was determined to be a suitable bioindicator of low (1-5 mg PCP/L) concentrations of PCP. These data provide a basis for the development of bioindicators of the presence of low concentrations of PCP in the environment and for understanding physiological and biochemical responses of Arabidopsis to exposure to PCP.