Contrasting plant–microbe interrelations on soil Di-(2-ethylhexyl) phthalate and pyrene degradation by three dicotyledonous plant species

Abstract

Plants and associated microbial communities can actively participate in the biodegradation of organic pollution. Potexperiments were conducted to explore the plant–microbe interrelations on Di-(2-ethylhexyl) phthalate (DEHP) and pyrene degradation in a soil culture system. Three dicotyledonous plant species, Ceylon spinach (Gynuracusimbua (D. Don) S. Moore), sunflower (Helianthus annuus L.), and Shuidong mustard (Brassica juncea (L.) Coss.var. foliosa Bailey), were cultivated for 45 days in DEHP and pyrene co-contaminated soils using three initial content levels: 0 (T0), 20 (T20) and 50 mg kg−1 (T50) with no plants (NP) as control. The results demonstrated that Shuidong mustard biomass and sunflower biomass had significantly positive correlations with the removal rate of DEHP (P < .05), respectively, while Ceylon spinach biomass has no significant correlation with the removal rate of DEHP. Shuidong mustard–actinomycetes and Ceylon spinach–actinomycetes accelerated the removal rate of pyrene, and sunflower–gram-positive bacteria could also enhance the removal rate of pyrene. Our results suggest that a better understanding of plant–microbe interrelations could be exploited to enhance the phytoremediation of organic co-contaminated soils.

Keywords

• actinomycete
• arbuscular mycorrhizal fungus
• di-(2-ethylhexyl) phthalate
• pyrene
• phospholipid fatty acids (plfas)