Abstract: Experiments on degradation of phenanthrene by two species of petroleum-degrading bacteria and the change of dioxygenase activities were carried out.The results indicated that when the phenanthrene concentration was 100 mg稬^-1, phenanthrenee degradation was the highest.When the phenanthrene concentration was higher than 100 mg稬^-1,the degradation decreased.There was a significant correlation between phenanthrene degradation and dioxygenase activities when the phenanthrene concentration ranged from 50 to 250 mg稬^-1.The dioxygenase activities could be used as an effective assessment index of phenanthrene degradation process and intensity.

Key words: Soybean, Faba bean, Root system, Configuration parameter, Spatial distribution