Die Bodenkultur - Journal for Land Management, Food and Environment

G. Höflich and Th. Günther:

Effect of plant-rhizosphere microorganism-associations on the degradation of polycyclic aromatic hydrocarbons in soil


The degradation of the polycyclic aromatic hydrocarbons (PAH) anthracene and pyrene (each 50 mg kg -1 soil) in the root zone of different plants was investigated in pot experiments with loamy sand. The PAHs inhibited the plant growth, but the stimulated rhizosphere bacteria accelerated the degradation of anthracene in the soil of the root zone of wheat, oat, ryegrass and pea. The degradation of pyrene was only accelerated in the root zone of ryegrasses. Inoculation of seedlings with selected plant growth promoting bacteria enhanced the plant growth in PAH contaminated soils. The degradation of PAH was stimulated by Agrobacterium rhizogenes (A1A4) in assoziation with wheath, ryegrass and maize and by Pseudomonasjluorescens in association with maize. There were no correlations between plant growth stimulation and PAH-degradation.

Key words:  Polyeyclic aromatic hydrocarbons, degradation, plant, rhizosphere bacteria.