Intra-specific variability of the guaiacol peroxidase (GPOD) activity in roots of Phragmites australis exposed to copper excess

Abstract

The intra-specific variability of the soluble guaiacol peroxidase (GPOD) activity in roots of 2-year-old Phragmites australis (Cav.) Trin. ex Steud. exposed to Cu excess (21 days) was investigated. The GPOD activity did not depend on the Cu exposure (0.08 vs. 25μM) (p>0.05) but was influenced by the sampling site (p<0.05). The lowest GPOD activity (312-461μMmin−1) was found in roots of P. australis from the Capanne site, which displayed the highest total soil Cu (375mgkg−1), while for plants from the three other sites the root GPOD activity remained steady, in the 1062-1389μMmin−1 range, independently of the sampling site. Copper excess did not affect the chlorophyll fluorescence for the four populations tested. Evidence of an intra-specific variability of the root GPOD activity, known for scavenging hydrogen peroxides in response to Cu excess, for P. australis provides new hints towards choosing relevant populations of this plant species for further use in constructed wetlands.